Merge branch 'main' into cad-mainline

tests/AGENTS.md

@@ -10,16 +10,17 @@ Rules for writing tests under `tests/`. [CATCH2.md](CATCH2.md) is the Catch2 ref
 - `libnest2d`: 2D nesting and packing.
 - `slic3rutils`: the Python plugin system and its slicing-pipeline bindings.
 - `filament_group`: filament-to-extruder grouping, checked against golden files.
+- `cli`: end-to-end runs of the built `orca-slicer` binary, Linux only. These tests carry the `RequiresApp` label, which the CI unit-test job excludes because it receives only `build/tests`; run them with `ctest --test-dir build/tests -C Release -L RequiresApp`.
 
 ## Building and running
 
 Tests are off by default, so the build has to be told to include them.
 
-- Windows: `build_release_vs.bat tests`, then `ctest --test-dir build/tests -C Release`
+- Windows: `build_win.bat -ds --run-tests`, which builds the dependencies and the tests and runs them (`-l -x` for the clang-cl and Ninja build CI uses)
 - macOS: `./build_release_macos.sh -s -a arm64 -T`, which builds and runs them
-- Linux: `./build_linux.sh -t`, then `ctest --test-dir build/tests`
+- Linux: `./build_linux.sh -t`, then `ctest --test-dir build/tests -C Release`
 
-Rebuild a single suite with `cmake --build build --config Release --target <suite>_tests`. Visual Studio and Xcode are multi-configuration generators, so `ctest` needs `-C` there; on Linux it does not.
+Rebuild a single suite with `cmake --build build --config Release --target <suite>_tests`. Visual Studio, Xcode and the Ninja Multi-Config generator that `build_linux.sh` uses are all multi-configuration, so `ctest` needs `-C` on every platform; without it, tests registered with plain `add_test()` lose their labels and report "Not Run".
 
 ## Where a test goes
 

tests/CMakeLists.txt

@@ -85,4 +85,9 @@ add_subdirectory(fff_print)
 add_subdirectory(sla_print)
 add_subdirectory(filament_group)
 
+# End-to-end checks of the orca-slicer binary. Linux only: they read result.json, which the CLI
+# writes on Linux only. src/ is added before tests/, so the target is known here.
+if (UNIX AND NOT APPLE AND TARGET OrcaSlicer)
+    add_subdirectory(cli)
+endif ()
 

tests/cli/CMakeLists.txt

@@ -0,0 +1,17 @@
+# Runs the real orca-slicer binary, so it needs the built app and resources/, not just build/tests.
+# The CI unit-test job only receives build/tests, so the test carries the RequiresApp label that
+# scripts/run_unit_tests.sh excludes. Run it with `ctest -C Release -L RequiresApp`. It also exits 77
+# (skipped) when the binary is missing.
+
+find_program(ORCA_CLI_TEST_PYTHON NAMES python3)
+if (NOT ORCA_CLI_TEST_PYTHON)
+    message(STATUS "python3 not found, not registering the CLI tests")
+    return()
+endif ()
+
+add_test(NAME cli_strict_mode
+    COMMAND bash ${CMAKE_CURRENT_SOURCE_DIR}/test_cli_strict.sh $<TARGET_FILE:OrcaSlicer> ${ORCA_CLI_TEST_PYTHON})
+set_tests_properties(cli_strict_mode PROPERTIES
+    LABELS "CLI;RequiresApp"
+    SKIP_RETURN_CODE 77
+    TIMEOUT 900)

tests/cli/test_cli_strict.sh

@@ -0,0 +1,153 @@
+#!/usr/bin/env bash
+# End-to-end check of the CLI --strict option against the real orca-slicer binary.
+#
+# A model with a large unsupported overhang, sliced with support off, raises the NON_CRITICAL
+# "support needed" slicing warning. The CLI lists it in result.json's "warnings" array, and with
+# --strict it also fails the run with CLI_SLICING_ERROR. --strict with --no-check is rejected up
+# front, because --no-check skips that check.
+#
+# usage: test_cli_strict.sh <orca-slicer binary> <python3>
+set -u
+
+BIN="${1:-}"
+PY="${2:-python3}"
+# 77 is the test's SKIP_RETURN_CODE.
+[ -x "$BIN" ] || { echo "SKIP: orca-slicer binary not found: $BIN"; exit 77; }
+
+# From src/libslic3r/Utils.hpp. main() returns them, so the shell sees them modulo 256.
+CLI_SUCCESS=0
+CLI_INVALID_PARAMS=-2
+CLI_SLICING_ERROR=-100
+
+WORK="$(mktemp -d "${TMPDIR:-/tmp}/orca-cli-strict.XXXXXX")"
+trap 'rm -rf "$WORK"' EXIT
+mkdir -p "$WORK/datadir"
+
+# Standalone presets: without "inherits" the CLI loads them as-is, with no preset bundle.
+cat > "$WORK/machine.json" <<'EOF'
+{
+    "type": "machine",
+    "from": "User",
+    "name": "CLI strict test printer",
+    "printable_area": ["0x0", "200x0", "200x200", "0x200"],
+    "printable_height": "100",
+    "layer_change_gcode": "G92 E0"
+}
+EOF
+cat > "$WORK/process.json" <<'EOF'
+{
+    "type": "process",
+    "from": "User",
+    "name": "CLI strict test process",
+    "enable_support": "0",
+    "enforce_support_layers": "0"
+}
+EOF
+
+# A 40x40mm cap on an 8x8mm stem: the cap reaches ~22mm past the stem, beyond the 6mm
+# cantilever limit of PrintObject::is_support_necessary().
+"$PY" - "$WORK/capital.stl" <<'EOF'
+import sys
+
+def box(x0, y0, z0, x1, y1, z1):
+    v = [(x, y, z) for z in (z0, z1) for y in (y0, y1) for x in (x0, x1)]
+    # Faces wound counter-clockwise seen from outside: -z, +z, -y, +y, -x, +x.
+    for a, b, c, d in ((0, 2, 3, 1), (4, 5, 7, 6), (0, 1, 5, 4), (2, 6, 7, 3), (0, 4, 6, 2), (1, 3, 7, 5)):
+        yield v[a], v[b], v[c]
+        yield v[a], v[c], v[d]
+
+with open(sys.argv[1], "w") as f:
+    f.write("solid capital\n")
+    for tri in (*box(16, 16, 0, 24, 24, 13), *box(0, 0, 12, 40, 40, 14)):
+        f.write("facet normal 0 0 0\nouter loop\n")
+        for p in tri:
+            f.write("vertex %g %g %g\n" % p)
+        f.write("endloop\nendfacet\n")
+    f.write("endsolid capital\n")
+EOF
+
+fails=0
+fail() { echo "FAIL: $*"; fails=$((fails + 1)); }
+
+# run <tag> [option...]: slice into $WORK/<tag>, keeping the log and the shell status there.
+run() {
+    local out="$WORK/$1"; shift
+    mkdir -p "$out"
+    timeout 300 "$BIN" --datadir "$WORK/datadir" --load-settings "$WORK/machine.json;$WORK/process.json" \
+        "$@" --slice 0 --outputdir "$out" "$WORK/capital.stl" > "$out/log" 2>&1
+    echo $? > "$out/status"
+}
+
+# expect_status <tag> <cli code>
+expect_status() {
+    local got; got="$(cat "$WORK/$1/status")"
+    [ "$got" -eq $(( $2 & 255 )) ] || fail "$1: shell status $got, want $(( $2 & 255 )) (code $2)"
+}
+
+# expect_gcode <tag> yes|no
+expect_gcode() {
+    if compgen -G "$WORK/$1/*.gcode" > /dev/null; then
+        [ "$2" = yes ] || fail "$1: G-code was exported"
+    else
+        [ "$2" = no ] || fail "$1: no G-code was exported"
+    fi
+}
+
+# expect_result <tag> <return_code> <strict_mode true|false> <non-critical warning: some|none>
+expect_result() {
+    "$PY" - "$WORK/$1/result.json" "$2" "$3" "$4" <<'EOF' || fail "$1: result.json"
+import json, sys
+
+path, want_rc, want_strict, want_warning = sys.argv[1], int(sys.argv[2]), sys.argv[3] == "true", sys.argv[4]
+try:
+    with open(path) as f:
+        result = json.load(f)
+except (OSError, ValueError) as e:
+    sys.exit("cannot read %s: %s" % (path, e))
+
+errors = []
+if result.get("return_code") != want_rc:
+    errors.append("return_code %r, want %d" % (result.get("return_code"), want_rc))
+if result.get("strict_mode") is not want_strict:
+    errors.append("strict_mode %r, want %r" % (result.get("strict_mode"), want_strict))
+warnings = result.get("warnings")
+if not isinstance(warnings, list):
+    errors.append("warnings %r is not a list" % (warnings,))
+else:
+    found = any(isinstance(w, dict) and w.get("class") == "slicing_warning_non_critical" for w in warnings)
+    if found != (want_warning == "some"):
+        errors.append("warnings %r, want %s slicing_warning_non_critical" % (warnings, want_warning))
+for e in errors:
+    print(e)
+sys.exit(1 if errors else 0)
+EOF
+}
+
+echo "== without --strict the warning is listed and the slice succeeds"
+run plain
+expect_status plain $CLI_SUCCESS
+expect_result plain $CLI_SUCCESS false some
+expect_gcode plain yes
+
+echo "== --strict fails the run on the same warning, before G-code export"
+run strict --strict
+expect_status strict $CLI_SLICING_ERROR
+expect_result strict $CLI_SLICING_ERROR true some
+expect_gcode strict no
+
+echo "== --strict with --no-check is rejected before slicing"
+run conflict --strict --no-check
+expect_status conflict $CLI_INVALID_PARAMS
+expect_result conflict $CLI_INVALID_PARAMS true none
+expect_gcode conflict no
+grep -q -- "--strict cannot be combined with --no-check" "$WORK/conflict/log" \
+    || fail "conflict: error message missing"
+
+if [ "$fails" -ne 0 ]; then
+    for log in "$WORK"/*/log; do
+        echo "--- $log"
+        tail -n 40 "$log"
+    done
+    exit 1
+fi
+echo "PASS"

tests/fff_print/CMakeLists.txt

@@ -21,6 +21,7 @@ add_executable(${_TEST_NAME}_tests
 	test_support_material.cpp
 	test_tree_support.cpp
 	test_trianglemesh.cpp
+	test_wipe.cpp
 	test_wipe_tower.cpp
 	)
 target_link_libraries(${_TEST_NAME}_tests test_common libslic3r Catch2::Catch2WithMain)

tests/fff_print/test_fill.cpp

@@ -9,11 +9,13 @@
 #include <vector>
 
 #include "libslic3r/ClipperUtils.hpp"
+#include "libslic3r/AABBTreeLines.hpp"
 #include "libslic3r/Fill/Fill.hpp"
 #include "libslic3r/Flow.hpp"
 #include "libslic3r/Geometry.hpp"
 #include "libslic3r/Layer.hpp"
 #include "libslic3r/Print.hpp"
+#include "libslic3r/PrintConfig.hpp"
 #include "libslic3r/SVG.hpp"
 #include "libslic3r/libslic3r.h"
 
@@ -675,6 +677,73 @@ TEST_CASE("Ironing follows the solid infill rotation template", "[Fill]")
     REQUIRE(compared > int(ironing.size()) / 2);
 }
 
+
+namespace {
+
+PrintRegionConfig ironing_config(IroningType type,
+                                 int top_surface_filament_id = 1,
+                                 int top_shell_layers        = 3,
+                                 int bottom_shell_layers     = 1)
+{
+    PrintRegionConfig cfg;
+    cfg.ironing_type.value            = type;
+    cfg.top_surface_filament_id.value = top_surface_filament_id;
+    cfg.top_shell_layers.value        = top_shell_layers;
+    cfg.bottom_shell_layers.value     = bottom_shell_layers;
+    cfg.outer_wall_filament_id.value  = 1;
+    cfg.wall_loops.value              = 2;
+    return cfg;
+}
+
+} // namespace
+
+TEST_CASE("Ironing an all-solid region uses the top surface filament on every layer", "[Fill]")
+{
+    const PrintRegionConfig cfg = ironing_config(IroningType::AllSolid, /*top_surface_filament_id=*/2);
+    const bool is_topmost_layer = GENERATE(false, true);
+    CAPTURE(is_topmost_layer);
+    REQUIRE(Layer::choose_ironing_extruder(cfg, /*spiral_mode=*/false, is_topmost_layer) == 2);
+}
+
+TEST_CASE("Ironing top surfaces uses the top surface filament when the region has top shells", "[Fill]")
+{
+    const PrintRegionConfig cfg = ironing_config(IroningType::TopSurfaces,
+                                                 /*top_surface_filament_id=*/3,
+                                                 /*top_shell_layers=*/2);
+    REQUIRE(Layer::choose_ironing_extruder(cfg, /*spiral_mode=*/false, /*is_topmost_layer=*/false) == 3);
+}
+
+TEST_CASE("Ironing top surfaces without top shells needs spiral mode and more than one bottom shell", "[Fill]")
+{
+    const PrintRegionConfig one_bottom_shell = ironing_config(IroningType::TopSurfaces,
+                                                              /*top_surface_filament_id=*/1,
+                                                              /*top_shell_layers=*/0,
+                                                              /*bottom_shell_layers=*/1);
+    const PrintRegionConfig two_bottom_shells = ironing_config(IroningType::TopSurfaces,
+                                                               /*top_surface_filament_id=*/1,
+                                                               /*top_shell_layers=*/0,
+                                                               /*bottom_shell_layers=*/2);
+
+    REQUIRE(Layer::choose_ironing_extruder(two_bottom_shells, /*spiral_mode=*/true, /*is_topmost_layer=*/false) == 1);
+    REQUIRE(Layer::choose_ironing_extruder(one_bottom_shell, /*spiral_mode=*/true, /*is_topmost_layer=*/false) == -1);
+    REQUIRE(Layer::choose_ironing_extruder(two_bottom_shells, /*spiral_mode=*/false, /*is_topmost_layer=*/false) == -1);
+}
+
+TEST_CASE("Ironing the topmost surface only applies to the topmost layer", "[Fill]")
+{
+    const PrintRegionConfig cfg = ironing_config(IroningType::TopmostOnly, /*top_surface_filament_id=*/4);
+    REQUIRE(Layer::choose_ironing_extruder(cfg, /*spiral_mode=*/false, /*is_topmost_layer=*/true) == 4);
+    REQUIRE(Layer::choose_ironing_extruder(cfg, /*spiral_mode=*/false, /*is_topmost_layer=*/false) == -1);
+}
+
+TEST_CASE("A region with ironing turned off is never ironed", "[Fill]")
+{
+    const PrintRegionConfig cfg = ironing_config(IroningType::NoIroning);
+    const bool spiral_mode      = GENERATE(false, true);
+    CAPTURE(spiral_mode);
+    REQUIRE(Layer::choose_ironing_extruder(cfg, spiral_mode, /*is_topmost_layer=*/true) == -1);
+}
+
 TEST_CASE("Solid infill direction offsets every layer when no template is set", "[Fill]")
 {
     auto angles_for = [](int direction) {
@@ -1229,3 +1298,68 @@ TEST_CASE("Smoothing multiline lightning infill keeps its outlines connected", "
     REQUIRE(smooth.point_count > sharp.point_count);
     REQUIRE(smooth.sharp_turns < sharp.sharp_turns);
 }
+
+TEST_CASE("Sparse plane-path anchors match the printed infill", "[Fill][InternalBridge][Regression]")
+{
+    // Orca: Compare generated anchors with actual extrusion across plane-path patterns,
+    // smoothing, multiline and rotations; an origin shift must not pass as valid support.
+    const std::string pattern = GENERATE("hilbertcurve", "octagramspiral", "archimedeanchords");
+    const std::string smoothing = GENERATE("0%", "100%");
+    const int multiline = GENERATE(1, 2);
+    const bool rotated = GENERATE(false, true);
+    const bool separated = GENERATE(false, true);
+    CAPTURE(pattern, smoothing, multiline, rotated, separated);
+
+    auto config = DynamicPrintConfig::full_print_config();
+    config.set_deserialize_strict({{"sparse_infill_pattern", pattern},
+                                   {"sparse_infill_density", "15%"},
+                                   {"sparse_infill_smooth_factor", smoothing},
+                                   {"fill_multiline", multiline},
+                                   {"infill_direction", 45},
+                                   {"sparse_infill_rotate_template", rotated ? "0,25,50" : ""},
+                                   {"align_infill_direction_to_model", rotated},
+                                   {"separated_infills", separated},
+                                   {"top_shell_layers", 0},
+                                   {"bottom_shell_layers", 0},
+                                   {"top_shell_thickness", 0},
+                                   {"bottom_shell_thickness", 0},
+                                   {"layer_height", 0.2},
+                                   {"initial_layer_print_height", 0.2},
+                                   {"resolution", 0.012}});
+    Print print;
+    Model model;
+    TriangleMesh mesh = make_cube(30, 24, 1);
+    if (separated) {
+        // Orca: Two disconnected bodies in one object must each use their own infill origin.
+        TriangleMesh second = make_cube(30, 24, 1);
+        second.translate(50, 0, 0);
+        mesh.merge(second);
+    }
+    Slic3r::Test::init_print({mesh}, print, model, config, nullptr, false);
+    if (rotated) {
+        model.objects.front()->instances.front()->set_rotation(Vec3d(0., 0., Geometry::deg2rad(23.)));
+        print.apply(model, config);
+    }
+    print.process();
+
+    const Layer &layer = *print.objects().front()->get_layer(4);
+    Polylines printed;
+    for (const LayerRegion *region : layer.regions())
+        for (const ExtrusionEntity *entity : region->fills.flatten().entities)
+            if (entity->role() == erInternalInfill)
+                entity->collect_polylines(printed);
+    REQUIRE_FALSE(printed.empty());
+    const AABBTreeLines::LinesDistancer<Line> printed_tree(to_lines(printed));
+
+    // Orca: Exclude perimeter connections: anchoring and extrusion can trim those differently.
+    const Polylines anchors = intersection_pl(layer.generate_sparse_infill_polylines_for_anchoring(nullptr, nullptr, nullptr),
+                                              shrink(to_polygons(layer.lslices), scale_(3.)));
+    REQUIRE_FALSE(anchors.empty());
+    double max_distance = 0.;
+    for (const Polyline &path : anchors)
+        for (const Point &point : path.equally_spaced_points(scale_(0.25)))
+            max_distance = std::max(max_distance, printed_tree.distance_from_lines<false>(point));
+    // Orca: Allow only the configured simplification tolerance; infill-scale offsets
+    // would hide anchors that no longer coincide with printed lines.
+    CHECK(unscale<double>(max_distance) <= config.opt_float("resolution"));
+}

tests/fff_print/test_gcodewriter.cpp

@@ -574,6 +574,9 @@ static DynamicPrintConfig dual_extruder_toolchange_config()
     config.set_key_value("nozzle_temperature_range_high", new ConfigOptionInts({240, 240}));
     config.set_key_value("flush_multiplier",     new ConfigOptionFloats({1}));
     config.set_key_value("flush_volumes_matrix", new ConfigOptionFloats({0, 140, 140, 0}));
+    // Inside the 200x200 test bed; the default y, 220, is not, and generation rejects that.
+    config.set_key_value("wipe_tower_x",         new ConfigOptionFloats({50.}));
+    config.set_key_value("wipe_tower_y",         new ConfigOptionFloats({50.}));
     return config;
 }
 

tests/fff_print/test_perimeters.cpp

@@ -4,9 +4,14 @@
 #include "libslic3r/ExtrusionEntityCollection.hpp"
 #include "libslic3r/Layer.hpp"
 #include "libslic3r/Print.hpp"
+#include "libslic3r/GCodeReader.hpp"
+#include "libslic3r/Model.hpp"
+#include "libslic3r/TriangleMesh.hpp"
 
 #include <algorithm>
 #include <cmath>
+#include <limits>
+#include <string>
 #include <vector>
 
 #include "test_helpers.hpp"
@@ -255,3 +260,238 @@ TEST_CASE("Only one wall on the first layer needs a bottom shell", "[Perimeters]
     // No bottom shell: the option is inert, down to the same walls an unchecked box gives.
     CHECK_THAT(one_wall_no_shell, Catch::Matchers::WithinAbs(plain_no_shell, 1.0));
 }
+
+namespace {
+
+// The layer that closes the cavity of box_over_cavity(), the first one printed over air.
+const double cavity_ceiling_z = 6.2;
+
+// A cone standing on its tip, flaring by 5mm of radius per mm of height: at a layer height of 0.2 every
+// wall of a layer lands a full millimetre outside the one below, entirely off the layer below but right
+// alongside the walls printed with it.
+TriangleMesh flared_cone()
+{
+    TriangleMesh cone = make_cone(20., 4.);
+    cone.mirror(Z);
+    cone.translate(0., 0., 4.);
+    return cone;
+}
+
+// A 30mm box holding a 20mm cavity from z=2 to z=6, with a 4mm hole punched down through the ceiling
+// of that cavity. The layer at cavity_ceiling_z bridges the cavity, and the walls of the hole sit in
+// the middle of that bridge, 15mm clear of anything the layer below supports.
+Print &box_over_cavity(Print &print, Model &model, const DynamicPrintConfig &config)
+{
+    ModelObject *object = model.add_object();
+    object->name = "box_over_cavity.stl";
+    object->add_volume(make_cube(30., 30., 8.), ModelVolumeType::MODEL_PART, false);
+    TriangleMesh cavity = make_cube(20., 20., 4.);
+    cavity.translate(5.f, 5.f, 2.f);
+    object->add_volume(std::move(cavity), ModelVolumeType::NEGATIVE_VOLUME, false);
+    TriangleMesh hole = make_cube(4., 4., 6.);
+    hole.translate(13.f, 13.f, 5.f);
+    object->add_volume(std::move(hole), ModelVolumeType::NEGATIVE_VOLUME, false);
+    object->add_instance();
+    object->ensure_on_bed();
+
+    print.auto_assign_extruders(object);
+    print.apply(model, config);
+    print.validate();
+    print.set_status_silent();
+    return print;
+}
+
+// Every setting the assertions below depend on, so none of them rests on a default.
+DynamicPrintConfig unsupported_walls_config(const char *wall_generator, bool unsupported_wall_last)
+{
+    DynamicPrintConfig config = DynamicPrintConfig::full_print_config();
+    config.set_deserialize_strict({
+        { "wall_generator",             wall_generator },
+        { "layer_height",               0.2 },
+        { "initial_layer_print_height", 0.2 },
+        { "wall_loops",                 3 },
+        { "detect_overhang_wall",       true },
+        // Outer wall first, so an unsupported loop only ends up last if the feature puts it there.
+        { "wall_sequence",              "outer wall/inner wall" },
+        { "is_infill_first",            false },
+        { "sparse_infill_density",      "15%" },
+        { "unsupported_wall_last",      unsupported_wall_last },
+        { "gcode_comments",             true },
+    });
+    return config;
+}
+
+// A loop extruded entirely in mid air: every one of its paths is an overhang.
+bool unsupported_loop(const ExtrusionEntity *entity)
+{
+    if (! entity->is_loop())
+        return false;
+    const ExtrusionPaths &paths = static_cast<const ExtrusionLoop *>(entity)->paths;
+    return ! paths.empty() && std::all_of(paths.begin(), paths.end(),
+                                          [](const ExtrusionPath &path) { return path.role() == erOverhangPerimeter; });
+}
+
+// The loops of every wall island of the print, island by island, in extrusion order.
+std::vector<std::vector<const ExtrusionLoop*>> wall_islands(const Print &print)
+{
+    std::vector<std::vector<const ExtrusionLoop*>> islands;
+    for (const Layer *layer : print.objects().front()->layers())
+        for (const LayerRegion *region : layer->regions())
+            for (const ExtrusionEntity *island : region->perimeters.entities) {
+                std::vector<const ExtrusionLoop*> loops;
+                for (const ExtrusionEntity *entity : static_cast<const ExtrusionEntityCollection*>(island)->entities)
+                    if (entity->is_loop())
+                        loops.push_back(static_cast<const ExtrusionLoop*>(entity));
+                islands.push_back(std::move(loops));
+            }
+    return islands;
+}
+
+// Islands where a loop that is anchored is extruded after one that is not.
+int islands_with_a_supported_loop_last(const Print &print)
+{
+    int count = 0;
+    for (const std::vector<const ExtrusionLoop*> &loops : wall_islands(print)) {
+        bool seen_unsupported = false;
+        for (const ExtrusionLoop *loop : loops) {
+            if (unsupported_loop(loop))
+                seen_unsupported = true;
+            else if (seen_unsupported) {
+                ++ count;
+                break;
+            }
+        }
+    }
+    return count;
+}
+
+// The unsupported loops of the print, and those of them held back for the infill.
+std::vector<const ExtrusionLoop*> unsupported_loops(const Print &print, double print_z = -1.)
+{
+    std::vector<const ExtrusionLoop*> loops;
+    for (const Layer *layer : print.objects().front()->layers()) {
+        if (print_z >= 0. && std::abs(layer->print_z - print_z) > EPSILON)
+            continue;
+        for (const LayerRegion *region : layer->regions())
+            for (const ExtrusionEntity *island : region->perimeters.entities)
+                for (const ExtrusionEntity *entity : static_cast<const ExtrusionEntityCollection*>(island)->entities)
+                    if (unsupported_loop(entity))
+                        loops.push_back(static_cast<const ExtrusionLoop*>(entity));
+    }
+    return loops;
+}
+
+int loops_held_back_for_infill(const std::vector<const ExtrusionLoop*> &loops)
+{
+    return int(std::count_if(loops.begin(), loops.end(), [](const ExtrusionLoop *loop) { return loop->print_after_infill; }));
+}
+
+// The G-code emitted at `print_z`, so the order of one layer can be read on its own.
+std::string layer_gcode(const std::string &gcode, double print_z)
+{
+    std::string out;
+    GCodeReader reader;
+    reader.parse_buffer(gcode, [&out, print_z](GCodeReader &self, const GCodeReader::GCodeLine &line) {
+        if (std::abs(self.z() - print_z) < EPSILON)
+            out += line.raw() + "\n";
+    });
+    return out;
+}
+
+} // namespace
+
+// Whatever the wall order asks for, a loop with nothing under it cannot be extruded before the loops it
+// leans on. The flared cone gives every layer an outer wall that lands completely off the one below, and
+// the outer wall first sequence would otherwise put it down before any of them.
+TEST_CASE("Unsupported wall loops are extruded after the walls that anchor them", "[Perimeters]")
+{
+    const char *wall_generator = GENERATE("classic", "arachne");
+    CAPTURE(wall_generator);
+
+    auto slice_cone = [wall_generator](bool unsupported_wall_last, Print &print) {
+        init_and_process_print({ flared_cone() }, print, unsupported_walls_config(wall_generator, unsupported_wall_last));
+        REQUIRE_FALSE(print.objects().empty());
+    };
+
+    Print on;
+    slice_cone(true, on);
+    // Without unsupported loops to reorder the rest of the test would pass on an empty print.
+    REQUIRE(unsupported_loops(on).size() > 0);
+    CHECK(islands_with_a_supported_loop_last(on) == 0);
+
+    SECTION("the held back loops run innermost first") {
+        for (const std::vector<const ExtrusionLoop*> &loops : wall_islands(on)) {
+            int previous_inset = std::numeric_limits<int>::max();
+            for (const ExtrusionLoop *loop : loops)
+                if (unsupported_loop(loop)) {
+                    CHECK(loop->inset_idx <= previous_inset);
+                    previous_inset = loop->inset_idx;
+                }
+        }
+    }
+
+    SECTION("switched off, the configured wall order is left alone") {
+        Print off;
+        slice_cone(false, off);
+        REQUIRE(unsupported_loops(off).size() == unsupported_loops(on).size());
+        // Outer wall first puts the unsupported outer wall ahead of the walls behind it.
+        CHECK(islands_with_a_supported_loop_last(off) > 0);
+    }
+}
+
+// A loop the walls cannot reach is a different case: only the bridges of its own layer will ever hold it,
+// so it has to wait for them - while a loop that runs alongside a wall keeps its place, because the
+// bridges anchor on it instead.
+TEST_CASE("A wall loop out of reach of the layer below waits for the infill", "[Perimeters]")
+{
+    const char *wall_generator = GENERATE("classic", "arachne");
+    CAPTURE(wall_generator);
+
+    Print print;
+    Model model;
+    box_over_cavity(print, model, unsupported_walls_config(wall_generator, true));
+    print.process();
+
+    const std::vector<const ExtrusionLoop*> hole_loops = unsupported_loops(print, cavity_ceiling_z);
+    REQUIRE(hole_loops.size() > 0);
+    CHECK(loops_held_back_for_infill(hole_loops) == int(hole_loops.size()));
+
+    SECTION("a loop alongside a supported wall is not held back") {
+        Print cone;
+        init_and_process_print({ flared_cone() }, cone, unsupported_walls_config(wall_generator, true));
+        const std::vector<const ExtrusionLoop*> loops = unsupported_loops(cone);
+        REQUIRE(loops.size() > 0);
+        CHECK(loops_held_back_for_infill(loops) == 0);
+    }
+
+    SECTION("switched off, no loop is held back") {
+        Print off;
+        Model off_model;
+        box_over_cavity(off, off_model, unsupported_walls_config(wall_generator, false));
+        off.process();
+        const std::vector<const ExtrusionLoop*> loops = unsupported_loops(off, cavity_ceiling_z);
+        REQUIRE(loops.size() == hole_loops.size());
+        CHECK(loops_held_back_for_infill(loops) == 0);
+    }
+}
+
+// The held back loops reach the G-code in a second pass, after the infill of their layer: on the layer
+// that closes the cavity the walls of the hole are extruded once the bridge is down, so the layer emits
+// perimeters, then infill, then the perimeters that were waiting for it.
+TEST_CASE("Loops waiting for the infill are extruded after it", "[Perimeters]")
+{
+    const char *wall_generator = GENERATE("classic", "arachne");
+    CAPTURE(wall_generator);
+
+    auto ceiling_roles = [wall_generator](bool unsupported_wall_last) {
+        Print print;
+        Model model;
+        box_over_cavity(print, model, unsupported_walls_config(wall_generator, unsupported_wall_last));
+        const std::string layer = layer_gcode(gcode(print), cavity_ceiling_z);
+        REQUIRE_FALSE(layer.empty());
+        return role_sequence(layer, { "perimeter", "infill" });
+    };
+
+    CHECK(ceiling_roles(true)  == std::vector<std::string>{ "perimeter", "infill", "perimeter" });
+    CHECK(ceiling_roles(false) == std::vector<std::string>{ "perimeter", "infill" });
+}

tests/fff_print/test_printobject.cpp

@@ -4,11 +4,18 @@
 #include "libslic3r/Print.hpp"
 #include "libslic3r/Layer.hpp"
 #include "libslic3r/GCodeReader.hpp"
+#include "libslic3r/ClipperUtils.hpp"
+#include "libslic3r/AABBTreeLines.hpp"
 
 #include "test_helpers.hpp"
 
+#include <cmath>
 #include <iterator>
+#include <map>
 #include <set>
+#include <string>
+#include <utility>
+#include <vector>
 
 using namespace Slic3r;
 using namespace Slic3r::Test;
@@ -130,3 +137,438 @@ TEST_CASE("Initial layer height is honored", "[PrintObject]")
     REQUIRE_THAT(*layer_zs.begin(),            Catch::Matchers::WithinAbs(0.3, 1e-4));
     REQUIRE_THAT(*std::next(layer_zs.begin()), Catch::Matchers::WithinAbs(0.5, 1e-4));
 }
+
+static TriangleMesh internal_bridge_step()
+{
+    // Orca: The smaller tower leaves a shoulder whose solid skin needs internal bridges
+    // over the sparse infill in the base, without relying on an external model file.
+    TriangleMesh mesh = make_cube(30, 24, 3);
+    TriangleMesh tower = make_cube(14, 10, 1);
+    tower.translate(8, 7, 3);
+    mesh.merge(tower);
+    return mesh;
+}
+
+static DynamicPrintConfig internal_bridge_config(const std::string &pattern, int multiline)
+{
+    auto config = DynamicPrintConfig::full_print_config();
+    config.set_deserialize_strict({{"sparse_infill_pattern", pattern},
+                                   {"fill_multiline", multiline},
+                                   {"sparse_infill_density", "15%"},
+                                   {"sparse_infill_smooth_factor", "100%"},
+                                   {"infill_direction", 45},
+                                   {"internal_bridge_angle", 0},
+                                   {"thick_internal_bridges", true},
+                                   {"top_shell_layers", 3},
+                                   {"bottom_shell_layers", 2},
+                                   {"top_shell_thickness", 0},
+                                   {"bottom_shell_thickness", 0},
+                                   {"layer_height", 0.2},
+                                   {"initial_layer_print_height", 0.2}});
+    return config;
+}
+
+TEST_CASE("Internal bridge angles follow the lower infill layer and model rotation", "[PrintObject][InternalBridge][Regression]")
+{
+    const std::string pattern = GENERATE("hilbertcurve", "octagramspiral");
+    // Orca: Cover both a central line (odd counts) and offset pairs (even counts).
+    const int multiline = GENERATE(1, 2, 3);
+    CAPTURE(multiline);
+    const double rotation = GENERATE(23., -123.);
+    const std::vector<double> cycle{10., 30., 70.};
+    auto config = internal_bridge_config(pattern, multiline);
+    config.set_deserialize_strict({{"sparse_infill_rotate_template", "10,30,70"},
+                                   {"align_infill_direction_to_model", true},
+                                   {"separated_infills", false}});
+    Print print;
+    Model model;
+    init_print({internal_bridge_step()}, print, model, config, nullptr, false);
+    model.objects.front()->instances.front()->set_rotation(Vec3d(0., 0., Geometry::deg2rad(rotation)));
+    print.apply(model, config);
+    print.process();
+    const PrintObject &object = *print.objects().front();
+    size_t bridges = 0;
+    for (size_t i = 1; i < object.layer_count(); ++i) {
+        // Orca: The support is one layer below the bridge. Check the template and model
+        // rotation together, including normalization when the resulting angle is negative.
+        double expected = std::fmod(cycle[(i - 1) % cycle.size()] + 90. + rotation, 180.);
+        if (expected < 0.) expected += 180.;
+        for (const LayerRegion *region : object.get_layer(i)->regions())
+            for (const Surface *surface : region->fill_surfaces.filter_by_type(stInternalBridge)) {
+                CAPTURE(pattern, rotation, i);
+                CHECK_THAT(Geometry::rad2deg(surface->bridge_angle), Catch::Matchers::WithinAbs(expected, 0.001));
+                ++bridges;
+            }
+    }
+    REQUIRE(bridges > 0);
+}
+
+TEST_CASE("Turning infill does not replace the anchors of another region", "[PrintObject][InternalBridge][Regression]")
+{
+    // Orca: Keep the right-hand region fixed while changing the left-hand pattern in the
+    // same object. Its bridge areas must be independent of a previous candidate's anchors.
+    const int multiline = GENERATE(1, 2, 3);
+    CAPTURE(multiline);
+    auto right_bridges = [multiline](const std::string &left_pattern) {
+        auto config = internal_bridge_config(left_pattern, multiline);
+        Print print;
+        Model model;
+        init_print({internal_bridge_step()}, print, model, config, nullptr, false);
+        TriangleMesh right = internal_bridge_step();
+        right.translate(50, 0, 0);
+        ModelVolume *volume = model.objects.front()->add_volume(std::move(right));
+        volume->config.set_key_value("sparse_infill_pattern", new ConfigOptionEnum<InfillPattern>(ipRectilinear));
+        volume->config.set_key_value("infill_direction", new ConfigOptionFloat(17.));
+        print.apply(model, config);
+        print.process();
+        std::map<size_t, Polygons> result;
+        const PrintObject &object = *print.objects().front();
+        for (size_t i = 0; i < object.layer_count(); ++i)
+            for (const LayerRegion *region : object.get_layer(i)->regions())
+                if (region->region().config().infill_direction == 17.)
+                    polygons_append(result[i], to_polygons(region->fill_surfaces.filter_by_type(stInternalBridge)));
+        return result;
+    };
+    const auto baseline = right_bridges("rectilinear");
+    const auto actual = right_bridges(GENERATE("hilbertcurve", "octagramspiral"));
+    REQUIRE(actual.size() == baseline.size());
+    double total_area = 0.;
+    for (const auto &[layer, expected] : baseline) {
+        CAPTURE(layer);
+        const auto &polys = actual.at(layer);
+        CHECK(area(diff(expected, polys)) < scaled<double>(1.) * scaled<double>(1.) * 1e-6);
+        CHECK(area(diff(polys, expected)) < scaled<double>(1.) * scaled<double>(1.) * 1e-6);
+        total_area += area(expected);
+    }
+    REQUIRE(total_area > 0.);
+}
+
+TEST_CASE("Rounded internal bridges end on printed support", "[PrintObject][InternalBridge][Regression]")
+{
+    const std::string pattern = GENERATE("hilbertcurve", "octagramspiral");
+    const bool separated = GENERATE(false, true);
+    CAPTURE(pattern, separated);
+    auto config = internal_bridge_config(pattern, 1);
+    config.set_deserialize_strict({{"infill_wall_overlap", "0%"}, {"separated_infills", separated}});
+    TriangleMesh mesh = internal_bridge_step();
+    if (separated) {
+        TriangleMesh second = internal_bridge_step();
+        second.translate(50, 0, 0);
+        mesh.merge(second);
+    }
+    Print print;
+    Model model;
+    init_print({mesh}, print, model, config, nullptr, false);
+    print.process();
+
+    // Orca: Check final extrusion endpoints after polygon cleanup and fill generation.
+    // A correct bridge angle and correct sparse anchors alone do not guarantee contact.
+    const PrintObject &object = *print.objects().front();
+    size_t checked = 0;
+    for (size_t i = 1; i < object.layer_count(); ++i) {
+        Polygons support;
+        Polylines walls;
+        for (const LayerRegion *region : object.get_layer(i - 1)->regions()) {
+            region->perimeters.polygons_covered_by_width(support, 0.f);
+            region->fills.polygons_covered_by_width(support, 0.f);
+            region->perimeters.collect_polylines(walls);
+        }
+        REQUIRE_FALSE(support.empty());
+        const AABBTreeLines::LinesDistancer<Line> support_tree(to_lines(union_(support)));
+        const AABBTreeLines::LinesDistancer<Line> wall_tree(to_lines(walls));
+        for (const LayerRegion *region : object.get_layer(i)->regions())
+            for (const ExtrusionEntity *entity : region->fills.flatten().entities) {
+                if (entity->role() != erInternalBridgeInfill)
+                    continue;
+                const auto *path = dynamic_cast<const ExtrusionPath *>(entity);
+                REQUIRE(path != nullptr);
+                for (const Line &line : path->polyline.to_polyline().lines()) {
+                    // Orca: Sample span ends, excluding short connectors and wall overlap.
+                    if (line.length() < scale_(std::max(0.7, 3. * path->width)))
+                        continue;
+                    for (const Point &point : {line.a, line.b}) {
+                        if (wall_tree.distance_from_lines<false>(point) <= scale_(0.5))
+                            continue;
+                        CAPTURE(i, point.x(), point.y());
+                        const double gap = unscale<double>(support_tree.distance_from_lines<true>(point)) - 0.5 * path->width;
+                        CHECK(gap <= 0.1);
+                        ++checked;
+                    }
+                }
+            }
+    }
+    REQUIRE(checked > 0);
+}
+
+TEST_CASE("Enabling separated infill recomputes body origins", "[PrintObject][InternalBridge][Regression]")
+{
+    const std::string pattern = GENERATE("hilbertcurve", "octagramspiral", "archimedeanchords");
+    CAPTURE(pattern);
+    auto footprint = [&](bool reslice) {
+        auto config = internal_bridge_config(pattern, 2);
+        config.set_deserialize_strict({{"separated_infills", !reslice}});
+        TriangleMesh mesh = internal_bridge_step();
+        TriangleMesh second = internal_bridge_step();
+        second.translate(50, 0, 0);
+        mesh.merge(second);
+        Print print;
+        Model model;
+        init_print({mesh}, print, model, config, nullptr, false);
+        print.process();
+        if (reslice) {
+            // Orca: Enabling centering after a completed slice must rebuild the body
+            // origins now shared by bridge preparation and printed infill.
+            config.set_deserialize_strict({{"separated_infills", true}});
+            print.apply(model, config);
+            print.process();
+        }
+        Polygons result;
+        for (const LayerRegion *region : print.objects().front()->get_layer(4)->regions())
+            region->fills.polygons_covered_by_width(result, 0.f);
+        return union_(result);
+    };
+    const Polygons fresh = footprint(false);
+    const Polygons resliced = footprint(true);
+    REQUIRE_FALSE(fresh.empty());
+    CHECK(area(diff(fresh, resliced)) < scaled<double>(1.) * scaled<double>(1.) * 1e-6);
+    CHECK(area(diff(resliced, fresh)) < scaled<double>(1.) * scaled<double>(1.) * 1e-6);
+}
+
+TEST_CASE("Surface centering survives changes to separated infill settings", "[PrintObject][SurfaceInfill][Regression]")
+{
+    const std::string pattern = GENERATE("archimedeanchords", "octagramspiral");
+    const std::string initial_center = GENERATE("each_surface", "each_model", "each_assembly");
+    const std::string final_center = GENERATE("each_surface", "each_model", "each_assembly");
+    const bool separated = GENERATE(false, true);
+    const std::string top_order = GENERATE("default", "outward", "inward");
+    const std::string bottom_order = top_order == "outward" ? "inward" : top_order == "inward" ? "outward" : "default";
+    const std::string density = GENERATE("80%", "100%");
+    const bool change_center = initial_center != final_center;
+    CAPTURE(pattern, initial_center, final_center, separated, top_order, bottom_order, density);
+
+    auto config = DynamicPrintConfig::full_print_config();
+    config.set_deserialize_strict({{"top_surface_pattern", pattern},
+                                   {"bottom_surface_pattern", pattern},
+                                   {"top_surface_fill_order", top_order},
+                                   {"bottom_surface_fill_order", bottom_order},
+                                   {"top_surface_density", density},
+                                   {"bottom_surface_density", density},
+                                   {"center_of_surface_pattern", initial_center},
+                                   {"separated_infills", change_center ? separated : !separated},
+                                   {"sparse_infill_pattern", "rectilinear"},
+                                   {"sparse_infill_density", "15%"},
+                                   {"top_shell_layers", 2},
+                                   {"bottom_shell_layers", 2},
+                                   {"top_shell_thickness", 0},
+                                   {"bottom_shell_thickness", 0},
+                                   {"layer_height", 0.2},
+                                   {"initial_layer_print_height", 0.2}});
+
+    // Orca: Two disconnected bodies exercise per-body centering. The offset tower also
+    // makes each-surface and each-model centering differ on the top surfaces.
+    TriangleMesh mesh = make_cube(30, 24, 2);
+    TriangleMesh tower = make_cube(12, 10, 1);
+    tower.translate(4, 3, 2);
+    mesh.merge(tower);
+    TriangleMesh second = mesh;
+    second.translate(50, 0, 0);
+    mesh.merge(second);
+
+    // Orca: Equal footprints can hide reordered or reversed paths. Retain their point
+    // sequences and ordering protection to cover the directional surface behavior too.
+    struct SurfaceFillSnapshot {
+        std::map<bool, std::vector<Points>> paths;
+        bool protected_order = true;
+    };
+    auto surface_fills = [](const Print &print) {
+        std::map<std::pair<size_t, ExtrusionRole>, SurfaceFillSnapshot> result;
+        const PrintObject &object = *print.objects().front();
+        for (size_t i = 0; i < object.layer_count(); ++i) {
+            auto collect = [&](const auto &self, const ExtrusionEntity &entity, bool no_sort) -> void {
+                if (const auto *collection = dynamic_cast<const ExtrusionEntityCollection *>(&entity)) {
+                    for (const ExtrusionEntity *child : collection->entities)
+                        self(self, *child, no_sort || collection->no_sort);
+                } else if (entity.role() == erTopSolidInfill || entity.role() == erBottomSurface) {
+                    const auto *path = dynamic_cast<const ExtrusionPath *>(&entity);
+                    REQUIRE(path != nullptr);
+                    auto &snapshot = result[{i, entity.role()}];
+                    // Orca: The centered test model has one body on either side of X=0.
+                    // Their traversal order may vary; preserve path order within each body.
+                    Points points = path->polyline.to_polyline().points;
+                    REQUIRE_FALSE(points.empty());
+                    snapshot.paths[points.front().x() > 0].push_back(std::move(points));
+                    snapshot.protected_order &= no_sort && !path->can_reverse();
+                }
+            };
+            for (const LayerRegion *region : object.get_layer(i)->regions())
+                collect(collect, region->fills, false);
+        }
+        return result;
+    };
+
+    Print print;
+    Model model;
+    init_print({mesh}, print, model, config, nullptr, false);
+    print.process();
+    const auto initial = surface_fills(print);
+    config.set_deserialize_strict({{"center_of_surface_pattern", final_center}, {"separated_infills", separated}});
+    print.apply(model, config);
+    // Orca: Preparation owns the body origins, and its invalidation must also force
+    // regeneration of top/bottom extrusion paths, even when sparse infill is unchanged.
+    CHECK_FALSE(print.objects().front()->is_step_done(posPrepareInfill));
+    CHECK_FALSE(print.objects().front()->is_step_done(posInfill));
+    print.process();
+    const auto resliced = surface_fills(print);
+
+    Print fresh_print;
+    Model fresh_model;
+    init_print({mesh}, fresh_print, fresh_model, config, nullptr, false);
+    fresh_print.process();
+    const auto fresh = surface_fills(fresh_print);
+    REQUIRE_FALSE(fresh.empty());
+    REQUIRE(resliced.size() == fresh.size());
+    std::set<ExtrusionRole> roles;
+    bool changed_paths = false;
+    for (const auto &entry : fresh) {
+        CAPTURE(entry.first.first, entry.first.second);
+        REQUIRE_FALSE(entry.second.paths.empty());
+        roles.insert(entry.first.second);
+        REQUIRE(resliced.count(entry.first) == 1);
+        REQUIRE(initial.count(entry.first) == 1);
+        const auto &actual = resliced.at(entry.first);
+        const auto &expected = entry.second;
+        const auto &before = initial.at(entry.first);
+        CHECK((actual.paths == expected.paths));
+        if (!change_center)
+            CHECK((actual.paths == before.paths));
+        if (top_order != "default") {
+            CHECK(expected.protected_order);
+            CHECK(actual.protected_order);
+            CHECK(before.protected_order);
+        }
+        changed_paths |= expected.paths != before.paths;
+    }
+    CHECK(roles.count(erTopSolidInfill) == 1);
+    CHECK(roles.count(erBottomSurface) == 1);
+    // Orca: Guard against a vacuous comparison: changing surface centering must change
+    // the printed pattern, while toggling separated sparse infill must leave it alone.
+    CHECK(changed_paths == change_center);
+}
+
+TEST_CASE("Separated infill keeps fragmented and nested bodies independent", "[PrintObject][SurfaceInfill][Regression]")
+{
+    constexpr size_t grid_size = 8;
+    TriangleMesh mesh;
+    auto add_box = [&](double x, double y, double width, double depth) {
+        TriangleMesh box = make_cube(width, depth, 0.6);
+        box.translate(x, y, 0);
+        mesh.merge(box);
+    };
+    // Orca: Many small islands exercise spatial pruning and the tree's original
+    // island indices. A pillar inside a frame also overlaps its bounding box,
+    // but must remain a separate body because it lies entirely inside the hole.
+    for (size_t x = 0; x < grid_size; ++ x)
+        for (size_t y = 0; y < grid_size; ++ y)
+            add_box(6 * x, 6 * y, 3, 3);
+    add_box(54, 0, 20, 4);
+    add_box(54, 16, 20, 4);
+    add_box(54, 0, 4, 20);
+    add_box(70, 0, 4, 20);
+    add_box(62, 8, 4, 4);
+
+    auto config = DynamicPrintConfig::full_print_config();
+    config.set_deserialize_strict({{"separated_infills", true},
+                                   {"center_of_surface_pattern", "each_surface"},
+                                   {"layer_height", 0.2},
+                                   {"initial_layer_print_height", 0.2},
+                                   {"elefant_foot_compensation", 0},
+                                   {"wall_loops", 1}});
+    Print print;
+    Model model;
+    init_print({mesh}, print, model, config, nullptr, false);
+    // Orca: Prepare body bounds through the public pipeline, then inspect the object read-only.
+    print.process();
+    const PrintObject &object = *print.objects().front();
+    REQUIRE(object.layer_count() > 1);
+    for (const Layer *layer : object.layers()) {
+        REQUIRE(layer->lslices.size() == grid_size * grid_size + 2);
+        REQUIRE(layer->lslices_separated_component_bboxes.size() == layer->lslices.size());
+        size_t holes = 0;
+        for (size_t i = 0; i < layer->lslices.size(); ++ i) {
+            const BoundingBox &body = layer->lslices_separated_component_bboxes[i];
+            const BoundingBox &island = layer->lslices_bboxes[i];
+            CHECK(body.min == island.min);
+            CHECK(body.max == island.max);
+            holes += layer->lslices[i].holes.size();
+        }
+        CHECK(holes == 1);
+    }
+}
+
+TEST_CASE("Body centering survives islands merging and splitting between layers", "[PrintObject][SurfaceInfill][Regression]")
+{
+    const bool separated = GENERATE(false, true);
+    CAPTURE(separated);
+    // Orca: Four posts join through horizontal then vertical rails, creating a
+    // cycle of overlaps before splitting into four islands again. This exercises
+    // redundant connections and indexing either adjacent layer. A fifth post
+    // stays separate at every height.
+    TriangleMesh mesh;
+    for (int x : {0, 8})
+        for (int y : {0, 8}) {
+            TriangleMesh post = make_cube(4, 4, 1);
+            post.translate(x, y, 0);
+            mesh.merge(post);
+        }
+    for (int y : {0, 8}) {
+        TriangleMesh rail = make_cube(12, 4, 0.2);
+        rail.translate(0, y, 0.2);
+        mesh.merge(rail);
+    }
+    for (int x : {0, 8}) {
+        TriangleMesh rail = make_cube(4, 12, 0.2);
+        rail.translate(x, 0, 0.4);
+        mesh.merge(rail);
+    }
+    TriangleMesh isolated = make_cube(4, 4, 1);
+    isolated.translate(20, 0, 0);
+    mesh.merge(isolated);
+
+    auto config = DynamicPrintConfig::full_print_config();
+    config.set_deserialize_strict({{"separated_infills", separated},
+                                   {"center_of_surface_pattern", separated ? "each_surface" : "each_model"},
+                                   {"layer_height", 0.2},
+                                   {"initial_layer_print_height", 0.2},
+                                   {"elefant_foot_compensation", 0},
+                                   {"wall_loops", 1}});
+    Print print;
+    Model model;
+    init_print({mesh}, print, model, config, nullptr, false);
+    // Orca: Prepare body bounds through the public pipeline, then inspect the object read-only.
+    print.process();
+    const PrintObject &object = *print.objects().front();
+    REQUIRE(object.layer_count() == 5);
+    REQUIRE(object.get_layer(0)->lslices.size() == 5);
+    REQUIRE(object.get_layer(1)->lslices.size() == 3);
+    REQUIRE(object.get_layer(2)->lslices.size() == 3);
+    REQUIRE(object.get_layer(4)->lslices.size() == 5);
+
+    BoundingBox isolated_bbox = object.get_layer(0)->lslices_bboxes.front();
+    for (const BoundingBox &bbox : object.get_layer(0)->lslices_bboxes)
+        if (bbox.min.x() > isolated_bbox.min.x())
+            isolated_bbox = bbox;
+    BoundingBox connected_bbox;
+    for (const Layer *layer : object.layers())
+        for (const BoundingBox &bbox : layer->lslices_bboxes)
+            if (bbox.min.x() < isolated_bbox.min.x())
+                connected_bbox.merge(bbox);
+    for (const Layer *layer : object.layers()) {
+        REQUIRE(layer->lslices_separated_component_bboxes.size() == layer->lslices.size());
+        for (size_t i = 0; i < layer->lslices.size(); ++ i) {
+            const BoundingBox &expected = layer->lslices_bboxes[i].min.x() < isolated_bbox.min.x() ? connected_bbox : isolated_bbox;
+            const BoundingBox &actual = layer->lslices_separated_component_bboxes[i];
+            CHECK(actual.min == expected.min);
+            CHECK(actual.max == expected.max);
+        }
+    }
+}

tests/fff_print/test_support_material.cpp

@@ -5,6 +5,7 @@
 
 #include <cmath>
 #include <map>
+#include <mutex>
 #include <set>
 #include <vector>
 
@@ -128,6 +129,49 @@ TEST_CASE("Enforced support layers are generated", "[SupportMaterial]")
     REQUIRE(enforced.objects().front()->support_layers().size() > 0);
 }
 
+// Support-needed statuses raised while slicing support_capital() with support off. The CLI lists these
+// in result.json and fails on them under --strict. Collected under a lock: generate_support_material()
+// runs on TBB workers.
+static std::vector<PrintBase::SlicingStatus> support_needed_statuses(bool no_check)
+{
+    Slic3r::Print print;
+    Slic3r::Model model;
+    Slic3r::Test::init_print({ support_capital() }, print, model, {
+        { "enable_support",         0 },
+        { "enforce_support_layers", 0 }
+    });
+    print.set_no_check_flag(no_check);
+
+    std::mutex mutex;
+    std::vector<PrintBase::SlicingStatus> statuses;
+    print.set_status_callback([&mutex, &statuses](const PrintBase::SlicingStatus &status) {
+        if (status.message_type != PrintStateBase::SlicingNeedSupportOn)
+            return;
+        std::lock_guard<std::mutex> lock(mutex);
+        statuses.push_back(status);
+    });
+    print.process();
+    return statuses;
+}
+
+TEST_CASE("An overhang sliced with support off reports that support is needed", "[SupportMaterial]")
+{
+    // The 40mm cap reaches ~22mm past its 8mm stem, beyond the 6mm cantilever limit of
+    // PrintObject::is_support_necessary().
+    const std::vector<PrintBase::SlicingStatus> statuses = support_needed_statuses(false);
+    REQUIRE(! statuses.empty());
+    for (const PrintBase::SlicingStatus &status : statuses) {
+        // The CLI only considers step warnings (warning_step != -1), and --strict only NON_CRITICAL ones.
+        CHECK(status.warning_level == PrintStateBase::WarningLevel::NON_CRITICAL);
+        CHECK(status.warning_step != -1);
+    }
+}
+
+TEST_CASE("The no-check flag skips the support-needed check", "[SupportMaterial]")
+{
+    CHECK(support_needed_statuses(true).empty());
+}
+
 SCENARIO("Support layer Z honors contact distance", "[SupportMaterial]")
 {
     // Box h = 20mm, hole bottom at 5mm, hole height 10mm (top edge at 15mm).

tests/fff_print/test_tree_support.cpp

@@ -1,5 +1,7 @@
 #include <catch2/catch_all.hpp>
 
+#include <algorithm>
+
 #include "libslic3r/Layer.hpp"
 #include "libslic3r/TriangleMesh.hpp"
 
@@ -33,10 +35,13 @@ TriangleMesh scaled(TestMesh id, float scale)
     return mesh;
 }
 
+// `extra` is applied last, so a caller can add or override any key.
 void slice_with_tree_support(const TriangleMesh &mesh, Slic3r::Print &print, const char *style,
-                             int threshold_angle = 30, int build_plate_only = 0, int raft_layers = 0)
+                             int threshold_angle = 30, int build_plate_only = 0, int raft_layers = 0,
+                             std::initializer_list<Slic3r::ConfigBase::SetDeserializeItem> extra = {})
 {
-    Slic3r::Test::init_and_process_print({ mesh }, print, {
+    DynamicPrintConfig config = DynamicPrintConfig::full_print_config();
+    config.set_deserialize_strict({
         { "enable_support",              1 },
         { "support_type",                "tree(auto)" },
         { "support_style",               style },
@@ -45,6 +50,8 @@ void slice_with_tree_support(const TriangleMesh &mesh, Slic3r::Print &print, con
         { "raft_layers",                 raft_layers },
         { "layer_height",                0.2 },
     });
+    config.set_deserialize_strict(extra);
+    Slic3r::Test::init_and_process_print({ mesh }, print, config);
 }
 
 Points support_points(const Slic3r::Print &print)
@@ -63,6 +70,32 @@ size_t support_point_count(const TriangleMesh &mesh, const char *style, int thre
     return support_points(print).size();
 }
 
+// Index of the first differing point, or the common length when they match. An index keeps a
+// failure readable; comparing the vectors themselves dumps thousands of points.
+size_t first_difference(const Points &a, const Points &b)
+{
+    const size_t common = std::min(a.size(), b.size());
+    for (size_t i = 0; i < common; ++i)
+        if (a[i] != b[i])
+            return i;
+    return common;
+}
+
+// Slice `mesh` twice and require an identical support point sequence. Point counts and total
+// length are order insensitive, so the sequence is what a reordering shows up in.
+void sliced_twice_matches(const TriangleMesh &mesh, int build_plate_only, const char *style = "tree_slim",
+                          std::initializer_list<Slic3r::ConfigBase::SetDeserializeItem> extra = {})
+{
+    Slic3r::Print first_print, second_print;
+    slice_with_tree_support(mesh, first_print, style, 30, build_plate_only, 0, extra);
+    slice_with_tree_support(mesh, second_print, style, 30, build_plate_only, 0, extra);
+    const Points first  = support_points(first_print);
+    const Points second = support_points(second_print);
+    REQUIRE(first.size() > 1000); // without support the comparison below passes vacuously
+    REQUIRE(second.size() == first.size());
+    REQUIRE(first_difference(first, second) == first.size());
+}
+
 } // namespace
 
 TEST_CASE("Tree support is generated for an overhang and not for a plain cube", "[TreeSupport]")
@@ -123,3 +156,35 @@ TEST_CASE("A raft is still generated under tree support", "[TreeSupport]")
     // The raft goes under the object.
     REQUIRE(rafted_object->layers().front()->print_z > unrafted_object->layers().front()->print_z);
 }
+
+// drop_nodes() decides the node merges and spawns the next layer's nodes in parallel. Every one of
+// those decisions has to be applied in a fixed order, or the same model gives different branches on
+// each slice.
+TEST_CASE("Tree support toolpaths do not depend on thread scheduling", "[TreeSupport][Regression]")
+{
+    // Scaled up so that a layer holds enough nodes for the parallel range to be split. At stock
+    // size it stays in one chunk and the order never varies.
+    SECTION("overhang")            { sliced_twice_matches(scaled(TestMesh::overhang, 2.f), 0); }
+    SECTION("bridge with hole")    { sliced_twice_matches(scaled(TestMesh::bridge_with_hole, 3.f), 0); }
+    // Dropping every branch that cannot reach the bed leaves the survivors dense enough that the
+    // neighbour merge fires in bulk.
+    SECTION("on the build plate")  { sliced_twice_matches(scaled(TestMesh::overhang, 4.f), 1); }
+    // Branches resting on the model are what put nodes in a part group other than 0, which is the
+    // only way to reach the prune in the second pass. tree_hybrid additionally builds polygon
+    // nodes, so it is the only style that exercises the overhang merge.
+    SECTION("resting on the model") { sliced_twice_matches(two_tier_mesh(), 0); }
+    SECTION("hybrid on the model")  { sliced_twice_matches(two_tier_mesh(), 0, "tree_hybrid"); }
+}
+
+// Prim breaks equal-distance ties by heap address. A 1 mm branch diameter puts neighbours close
+// enough to tie, and an explicit line width pins max_move_dist, so the moved tie winner reaches
+// the support toolpaths.
+TEST_CASE("Tree support toolpaths do not depend on the MST tie order", "[TreeSupport][Regression]")
+{
+    sliced_twice_matches(two_tier_mesh(), 0, "tree_hybrid", {
+        { "tree_support_branch_diameter", 1.0 },
+        { "tree_support_branch_distance", 5.0 },
+        { "tree_support_branch_angle",    40 },
+        { "support_line_width",           0.4 },
+    });
+}

tests/fff_print/test_wipe.cpp

@@ -0,0 +1,653 @@
+#include <catch2/catch_all.hpp>
+
+#include <algorithm>
+#include <cmath>
+#include <map>
+#include <string>
+#include <string_view>
+#include <vector>
+
+#include "libslic3r/GCode/GCodeProcessor.hpp"
+#include "libslic3r/GCodeReader.hpp"
+#include "libslic3r/PrintConfig.hpp"
+#include "libslic3r/Layer.hpp"
+
+#include "test_helpers.hpp"
+
+using namespace Slic3r;
+using namespace Slic3r::Test;
+
+namespace {
+
+DynamicPrintConfig wipe_config(const char *wall_generator, bool wipe_inward,
+                               const char *wipe_inward_distance = "50%",
+                               const char *seam_gap = "10%", bool wipe_on_loops = false,
+                               const char *wall_loops = "2",
+                               const char *wall_sequence = "inner wall/outer wall",
+                               bool alternate_extra_wall = false,
+                               const char *sparse_infill_density = "0%",
+                               const char *seam_position = "aligned")
+{
+    DynamicPrintConfig config = DynamicPrintConfig::full_print_config();
+    config.set_deserialize_strict({
+        { "nozzle_diameter",             "0.4" },
+        { "layer_height",                "0.2" },
+        { "initial_layer_print_height",  "0.2" },
+        { "line_width",                  "0.45" },
+        { "outer_wall_line_width",       "0" }, // Orca: Auto must use the actual path width.
+        { "wall_loops",                  wall_loops },
+        { "wall_generator",              wall_generator },
+        { "wall_sequence",               wall_sequence },
+        { "top_shell_layers",            "0" },
+        { "bottom_shell_layers",         "0" },
+        { "sparse_infill_density",       sparse_infill_density },
+        { "seam_position",               seam_position },
+        { "seam_gap",                    seam_gap },
+        { "wipe",                        "1" },
+        { "wipe_distance",               "2" },
+        { "retraction_length",           "0.8" },
+        { "retract_when_changing_layer", "1" },
+        { "wipe_inward",                 wipe_inward ? "1" : "0" },
+        { "wipe_inward_distance",        wipe_inward_distance },
+        { "wipe_on_loops",               wipe_on_loops ? "1" : "0" },
+        { "alternate_extra_wall",        alternate_extra_wall ? "1" : "0" },
+        { "gcode_comments",              "1" },
+        { "machine_start_gcode",         "" },
+        { "machine_end_gcode",           "" },
+    });
+    return config;
+}
+
+struct WipeTrajectory {
+    Vec2d start;
+    double z;
+    std::vector<Vec2d> destinations;
+};
+
+std::vector<WipeTrajectory> wipe_trajectories(const std::string &gcode)
+{
+    const std::string &start_tag = GCodeProcessor::reserved_tag(GCodeProcessor::ETags::Wipe_Start);
+    const std::string &end_tag   = GCodeProcessor::reserved_tag(GCodeProcessor::ETags::Wipe_End);
+    std::vector<WipeTrajectory> trajectories;
+    bool in_wipe = false;
+
+    GCodeReader parser;
+    parser.parse_buffer(gcode, [&](GCodeReader &self, const GCodeReader::GCodeLine &line) {
+        const std::string_view comment = line.comment();
+        if (comment.find(start_tag) != std::string_view::npos) {
+            in_wipe = true;
+            trajectories.push_back({Vec2d(self.x(), self.y()), self.z(), {}});
+            return;
+        }
+        if (comment.find(end_tag) != std::string_view::npos) {
+            in_wipe = false;
+            return;
+        }
+        if (in_wipe && line.dist_XY(self) > EPSILON)
+            trajectories.back().destinations.emplace_back(line.new_X(self), line.new_Y(self));
+    });
+    return trajectories;
+}
+
+std::vector<Vec2d> wipe_destinations(const std::string &gcode)
+{
+    std::vector<Vec2d> destinations;
+    for (const WipeTrajectory &trajectory : wipe_trajectories(gcode))
+        destinations.insert(destinations.end(), trajectory.destinations.begin(), trajectory.destinations.end());
+    return destinations;
+}
+
+bool trajectories_differ(const std::vector<Vec2d> &lhs, const std::vector<Vec2d> &rhs)
+{
+    if (lhs.size() != rhs.size())
+        return true;
+    for (size_t i = 0; i < lhs.size(); ++i)
+        if ((lhs[i] - rhs[i]).norm() > 0.01)
+            return true;
+    return false;
+}
+
+double trajectory_length(const WipeTrajectory &trajectory)
+{
+    double length = 0.;
+    Vec2d previous = trajectory.start;
+    for (const Vec2d &destination : trajectory.destinations) {
+        length += (destination - previous).norm();
+        previous = destination;
+    }
+    return length;
+}
+
+} // namespace
+
+TEST_CASE("Wipe retraction preserves fractional speed with inward wipe disabled", "[Wipe][Regression]")
+{
+    const char *retraction_speed = GENERATE("25.25", "25.5", "25.75");
+    const char *relative_e = GENERATE("0", "1");
+    INFO("retraction speed: " << retraction_speed);
+    INFO("relative E: " << relative_e);
+    DynamicPrintConfig config = wipe_config("classic", false);
+    config.set_deserialize_strict({
+        {"gcode_flavor", "marlin2"},
+        {"use_relative_e_distances", relative_e},
+        {"retraction_speed", retraction_speed},
+        {"retraction_length", "0.8"},
+        {"retract_before_wipe", "0%"},
+        {"retract_after_wipe", "0%"},
+        {"role_based_wipe_speed", "0"},
+        {"wipe_speed", "100"},
+        {"wipe_distance", "2"},
+    });
+    const std::string output = slice({make_cube(10., 10., 1.)}, config);
+    const auto &start_tag = GCodeProcessor::reserved_tag(GCodeProcessor::ETags::Wipe_Start);
+    const auto &end_tag = GCodeProcessor::reserved_tag(GCodeProcessor::ETags::Wipe_End);
+    double before_wipe = 0.;
+    double during_wipe = 0.;
+    bool in_wipe = false;
+    bool complete = false;
+    GCodeReader parser;
+    parser.apply_config(config);
+    parser.parse_buffer(output, [&](GCodeReader &self, const GCodeReader::GCodeLine &line) {
+        if (complete)
+            return;
+        if (line.comment().find(start_tag) != std::string_view::npos) {
+            in_wipe = true;
+        } else if (in_wipe && line.comment().find(end_tag) != std::string_view::npos) {
+            complete = true;
+        } else if (line.retracting(self)) {
+            (in_wipe ? during_wipe : before_wipe) -= line.dist_E(self);
+        } else if (line.extruding(self)) {
+            before_wipe = 0.;
+        }
+    });
+
+    REQUIRE(complete);
+    // At 100 mm/s, the 2 mm wipe lasts 0.02 seconds. The remaining part of
+    // the configured 0.8 mm retraction must be emitted before that wipe.
+    const double expected_during = std::stod(retraction_speed) * 2. / 100.;
+    CHECK_THAT(during_wipe, Catch::Matchers::WithinAbs(expected_during, 0.00005));
+    CHECK_THAT(before_wipe, Catch::Matchers::WithinAbs(0.8 - expected_during, 0.00005));
+}
+
+TEST_CASE("Inward wipe respects the minimum travel for retraction and Z hop", "[Wipe][Regression]")
+{
+    const char *wall_generator = GENERATE("classic", "arachne");
+    const char *relative_e = GENERATE("0", "1");
+    const char *reduce_crossing_wall = GENERATE("0", "1");
+    const char *minimum_travel = GENERATE("5", "0");
+    CAPTURE(wall_generator, relative_e, reduce_crossing_wall, minimum_travel);
+    DynamicPrintConfig config = wipe_config(
+        wall_generator, true, "50%", "10%", false, "3", "inner-outer-inner wall");
+    config.set_deserialize_strict({
+        {"gcode_flavor", "marlin2"},
+        {"use_relative_e_distances", relative_e},
+        {"reduce_crossing_wall", reduce_crossing_wall},
+        {"retraction_minimum_travel", minimum_travel},
+        {"retract_when_changing_layer", "0"},
+        {"use_firmware_retraction", "0"},
+        {"retract_before_wipe", "0%"},
+        {"retract_after_wipe", "0%"},
+        {"retraction_speed", "25.5"},
+        {"role_based_wipe_speed", "0"},
+        {"wipe_speed", "100"},
+        {"z_hop", "0.4"},
+        {"retract_lift_above", "0"},
+        {"retract_lift_below", "0"},
+    });
+    config.set_key_value("z_hop_types", new ConfigOptionEnumsGeneric{zhtNormal});
+    config.set_key_value("retract_lift_enforce", new ConfigOptionEnumsGeneric{rletAllSurfaces});
+    const std::string output = slice({make_cube(10., 10., 1.)}, config);
+    const auto &role_tag = GCodeProcessor::reserved_tag(GCodeProcessor::ETags::Role);
+    const auto &start_tag = GCodeProcessor::reserved_tag(GCodeProcessor::ETags::Wipe_Start);
+    const auto &end_tag = GCodeProcessor::reserved_tag(GCodeProcessor::ETags::Wipe_End);
+    ExtrusionRole role = erNone;
+    bool after_outer_wall = false;
+    bool in_wipe = false;
+    size_t transitions = 0;
+    size_t same_layer_transitions = 0;
+    size_t inward_wipes = 0;
+    double retraction = 0.;
+    double lift = 0.;
+    double outer_z = 0.;
+    GCodeReader parser;
+    parser.apply_config(config);
+    parser.parse_buffer(output, [&](GCodeReader &self, const GCodeReader::GCodeLine &line) {
+        if (line.comment().find(role_tag) == 0)
+            role = ExtrusionEntity::string_to_role(line.comment().substr(role_tag.size()));
+        if (line.comment().find(start_tag) == 0) {
+            in_wipe = true;
+            if (after_outer_wall)
+                ++inward_wipes;
+        } else if (line.comment().find(end_tag) == 0) {
+            in_wipe = false;
+        }
+        if (line.extruding(self) && line.dist_XY(self) > EPSILON) {
+            if (role == erExternalPerimeter) {
+                after_outer_wall = true;
+                retraction = lift = 0.;
+                outer_z = line.new_Z(self);
+            } else if (after_outer_wall) {
+                REQUIRE(role == erPerimeter);
+                ++transitions;
+                const double layer_rise = std::max(0., double(self.z()) - outer_z);
+                if (layer_rise < EPSILON)
+                    ++same_layer_transitions;
+                // A 5 mm threshold suppresses retraction across a few wall widths.
+                // A zero threshold still permits the ordinary retract and lift.
+                const bool retract = std::stod(minimum_travel) == 0.;
+                CHECK_THAT(retraction, Catch::Matchers::WithinAbs(retract ? 0.8 : 0., 0.00005));
+                // Exclude an ordinary layer change from the accumulated upward motion.
+                CHECK_THAT(lift - layer_rise, Catch::Matchers::WithinAbs(retract ? 0.4 : 0., 0.001));
+                after_outer_wall = false;
+            }
+        } else if (after_outer_wall) {
+            if (line.retracting(self))
+                retraction -= line.dist_E(self);
+            lift += std::max(0., double(line.dist_Z(self)));
+            if (in_wipe)
+                CHECK_THAT(line.dist_E(self), Catch::Matchers::WithinAbs(0., 0.00005));
+        }
+    });
+    // The 1 mm cube has five 0.2 mm layers: every outer wall must still wipe.
+    REQUIRE(transitions == 5);
+    REQUIRE(same_layer_transitions >= 4);
+    REQUIRE(inward_wipes == transitions);
+}
+
+TEST_CASE("Changing inward wipe settings preserves the sliced geometry", "[Wipe][Regression]")
+{
+    const char *key = GENERATE("wipe_inward", "wipe_inward_distance");
+    DynamicPrintConfig config = wipe_config("classic", false);
+    Print print;
+    Model model;
+    init_print({make_cube(10., 10., 1.)}, print, model, config);
+    gcode(print);
+    const PrintObject &object = *print.objects().front();
+    REQUIRE(object.is_step_done(posPerimeters));
+    REQUIRE(object.is_step_done(posInfill));
+    REQUIRE(print.is_step_done(psWipeTower));
+    REQUIRE(print.is_step_done(psGCodeExport));
+
+    DynamicPrintConfig changed = config;
+    changed.set_deserialize_strict({{key, std::string(key) == "wipe_inward" ? "1" : "75%"}});
+    print.apply(model, changed);
+
+    CHECK(print.objects().front()->is_step_done(posPerimeters));
+    CHECK(print.objects().front()->is_step_done(posInfill));
+    CHECK(print.is_step_done(psWipeTower));
+    CHECK_FALSE(print.is_step_done(psGCodeExport));
+}
+
+TEST_CASE("Retraction and pressure advance calibration suppress inward wipe overrides", "[Wipe][Regression]")
+{
+    const auto mode = GENERATE(CalibMode::Calib_None, CalibMode::Calib_PA_Tower,
+                              CalibMode::Calib_Auto_PA_Line, CalibMode::Calib_Retraction_tower,
+                              CalibMode::Calib_Flow_Rate);
+    const char *wall_generator = GENERATE("classic", "arachne");
+    const bool per_object = GENERATE(false, true);
+    INFO("calibration mode: " << int(mode) << ", wall generator: " << wall_generator
+         << ", per-object override: " << per_object);
+
+    const auto trajectories = [&](bool inward) {
+        DynamicPrintConfig config = wipe_config(wall_generator, inward && !per_object);
+        const std::vector<std::vector<ConfigBase::SetDeserializeItem>> overrides{
+            {{"wipe_inward", inward ? "1" : "0"}}
+        };
+        Print print;
+        Model model;
+        init_print({make_cube(10., 10., 1.)}, print, model, config, per_object ? &overrides : nullptr);
+        Calib_Params params;
+        params.mode = mode;
+        params.start = 0.2;
+        params.end = 0.4;
+        params.step = 0.1;
+        print.set_calib_params(params);
+        return wipe_destinations(gcode(print));
+    };
+
+    const auto regular = trajectories(false);
+    const auto inward = trajectories(true);
+    REQUIRE_FALSE(regular.empty());
+    REQUIRE_FALSE(inward.empty());
+    // Other calibration modes and ordinary prints must still honor the option.
+    const bool should_differ = mode == CalibMode::Calib_None || mode == CalibMode::Calib_Flow_Rate;
+    CHECK(trajectories_differ(regular, inward) == should_differ);
+}
+
+TEST_CASE("Inactive inward wipe settings preserve the exported trajectory", "[Wipe][Regression]")
+{
+    const char *wall_generator = GENERATE("classic", "arachne");
+    const bool disable_wiping = GENERATE(false, true);
+    DynamicPrintConfig regular = wipe_config(wall_generator, false);
+    DynamicPrintConfig inward = wipe_config(wall_generator, true, disable_wiping ? "50%" : "0");
+    if (disable_wiping) {
+        regular.set_deserialize_strict({{"wipe", "0"}});
+        inward.set_deserialize_strict({{"wipe", "0"}});
+    }
+    const auto regular_paths = wipe_destinations(slice({make_cube(10., 10., 1.)}, regular));
+    const auto inward_paths = wipe_destinations(slice({make_cube(10., 10., 1.)}, inward));
+    if (!disable_wiping)
+        REQUIRE_FALSE(regular_paths.empty());
+    CHECK_FALSE(trajectories_differ(regular_paths, inward_paths));
+}
+
+TEST_CASE("Inward wipe changes the exported trajectory when outer wall width is Auto", "[Wipe][Regression]")
+{
+    const char *wall_generator = GENERATE("classic", "arachne");
+    INFO("wall generator: " << wall_generator);
+
+    const std::vector<Vec2d> regular = wipe_destinations(
+        slice({make_cube(10., 10., 1.)}, wipe_config(wall_generator, false)));
+    const std::vector<Vec2d> inward = wipe_destinations(
+        slice({make_cube(10., 10., 1.)}, wipe_config(wall_generator, true)));
+
+    REQUIRE_FALSE(regular.empty());
+    REQUIRE_FALSE(inward.empty());
+    REQUIRE(trajectories_differ(regular, inward));
+}
+
+TEST_CASE("Inward wipe recognizes an external wall starting on an overhang", "[Wipe][Regression]")
+{
+    const char *wall_generator = GENERATE("classic", "arachne");
+    const bool inward = GENERATE(false, true);
+    CAPTURE(wall_generator, inward);
+    const auto config = wipe_config(wall_generator, inward, "50%", "0%", false,
+                                    "3", "inner-outer-inner wall", false, "0%", "back");
+    Print print;
+    Model model;
+    init_print({make_cube(10., 10., 1.)}, print, model, config);
+    print.process();
+    size_t mixed_loops = 0;
+    const auto mark_overhangs = [&](auto &&self, ExtrusionEntity *entity) -> void {
+        if (auto *collection = dynamic_cast<ExtrusionEntityCollection *>(entity)) {
+            for (ExtrusionEntity *child : collection->entities)
+                self(self, child);
+        } else if (auto *loop = dynamic_cast<ExtrusionLoop *>(entity); loop && is_external_perimeter(loop->role())) {
+            // Keep the printed geometry intact and give the back seam overhang
+            // roles. The front edge remains an ordinary external-wall segment.
+            ExtrusionPaths paths;
+            bool has_overhang = false;
+            bool has_external = false;
+            for (const ExtrusionPath &source : loop->paths) {
+                for (size_t i = 1; i < source.polyline.points.size(); ++i) {
+                    ExtrusionPath path = source;
+                    path.polyline.points = {source.polyline.points[i - 1], source.polyline.points[i]};
+                    const bool overhang = path.polyline.points.front().y() > 0 || path.polyline.points.back().y() > 0;
+                    path.set_extrusion_role(overhang ? erOverhangPerimeter : erExternalPerimeter);
+                    has_overhang |= overhang;
+                    has_external |= !overhang;
+                    paths.push_back(std::move(path));
+                }
+            }
+            REQUIRE(has_overhang);
+            REQUIRE(has_external);
+            loop->paths = std::move(paths);
+            ++mixed_loops;
+        }
+    };
+    for (const PrintObject *object : print.objects())
+        for (Layer *layer : object->layers())
+            for (LayerRegion *region : layer->regions())
+                mark_overhangs(mark_overhangs, &region->perimeters);
+    REQUIRE(mixed_loops > 0);
+
+    bool has_inward_wipe = false;
+    for (const WipeTrajectory &trajectory : wipe_trajectories(gcode(print))) {
+        if (trajectory.destinations.empty())
+            continue;
+        const Vec2d move = trajectory.destinations.front() - trajectory.start;
+        if (trajectory.start.x() > 4. && trajectory.start.y() > 4. && move.x() < -0.05 && move.y() < -0.05)
+            has_inward_wipe = true;
+    }
+    CHECK(has_inward_wipe == inward);
+}
+
+TEST_CASE("Inward wipe keeps its offset when seam gap is zero", "[Wipe][Regression]")
+{
+    const char *wall_generator = GENERATE("classic", "arachne");
+    INFO("wall generator: " << wall_generator);
+
+    const std::vector<Vec2d> regular = wipe_destinations(
+        slice({make_cube(10., 10., 1.)}, wipe_config(wall_generator, false, "50%", "0%")));
+    const std::vector<Vec2d> inward = wipe_destinations(
+        slice({make_cube(10., 10., 1.)}, wipe_config(wall_generator, true, "50%", "0%")));
+
+    REQUIRE_FALSE(regular.empty());
+    REQUIRE_FALSE(inward.empty());
+    REQUIRE(trajectories_differ(regular, inward));
+}
+
+TEST_CASE("Inward wipe is retained across layers with a back seam", "[Wipe][Regression]")
+{
+    const char *wall_generator = GENERATE("classic", "arachne");
+    INFO("wall generator: " << wall_generator);
+
+    const DynamicPrintConfig inward_config = wipe_config(
+        wall_generator, true, "50%", "0%", false, "3", "inner-outer-inner wall", false, "0%", "back");
+    const std::vector<WipeTrajectory> inward = wipe_trajectories(slice({make_cube(27., 27., 1.)}, inward_config));
+
+    REQUIRE_FALSE(inward.empty());
+    std::map<double, bool> inward_wipe_by_layer;
+    for (const WipeTrajectory &trajectory : inward) {
+        bool &has_inward_wipe = inward_wipe_by_layer[trajectory.z];
+        if (trajectory.destinations.empty())
+            continue;
+        const Vec2d first_move = trajectory.destinations.front() - trajectory.start;
+        // Orca: a back seam lands on the cube's positive-X/positive-Y corner.
+        // Its inward wipe must move diagonally away from both external faces.
+        has_inward_wipe = has_inward_wipe ||
+            (trajectory.start.x() > 13. && trajectory.start.y() > 13. &&
+             first_move.x() < -0.05 && first_move.y() < -0.05);
+    }
+    REQUIRE(inward_wipe_by_layer.size() == 5);
+    for (const auto &[z, has_inward_wipe] : inward_wipe_by_layer) {
+        INFO("layer Z: " << z);
+        REQUIRE(has_inward_wipe);
+    }
+}
+
+TEST_CASE("Literal inward wipe distance is clamped to the outer wall width", "[Wipe][Regression]")
+{
+    const char *wall_generator = GENERATE("classic", "arachne");
+    INFO("wall generator: " << wall_generator);
+
+    const std::vector<Vec2d> regular = wipe_destinations(
+        slice({make_cube(10., 10., 1.)}, wipe_config(wall_generator, false)));
+    const std::vector<Vec2d> full_width = wipe_destinations(
+        slice({make_cube(10., 10., 1.)}, wipe_config(wall_generator, true, "100%")));
+    const std::vector<Vec2d> oversized = wipe_destinations(
+        slice({make_cube(10., 10., 1.)}, wipe_config(wall_generator, true, "2")));
+
+    REQUIRE_FALSE(full_width.empty());
+    REQUIRE(trajectories_differ(regular, full_width));
+    REQUIRE(oversized.size() == full_width.size());
+    for (size_t i = 0; i < full_width.size(); ++i)
+        REQUIRE_THAT((oversized[i] - full_width[i]).norm(), Catch::Matchers::WithinAbs(0., 0.01));
+}
+
+TEST_CASE("Inward wipe is not applied without an adjacent wall", "[Wipe][Regression]")
+{
+    const char *wall_generator = GENERATE("classic", "arachne");
+    INFO("wall generator: " << wall_generator);
+
+    const std::vector<Vec2d> regular = wipe_destinations(
+        slice({make_cube(10., 10., 1.)}, wipe_config(wall_generator, false, "50%", "10%", false, "1")));
+    const std::vector<Vec2d> inward = wipe_destinations(
+        slice({make_cube(10., 10., 1.)}, wipe_config(wall_generator, true, "50%", "10%", false, "1")));
+
+    REQUIRE_FALSE(regular.empty());
+    REQUIRE_FALSE(trajectories_differ(regular, inward));
+}
+
+TEST_CASE("Inward wipe uses an alternate extra wall when the configured wall count is one", "[Wipe][Regression]")
+{
+    const char *wall_generator = GENERATE("classic", "arachne");
+    INFO("wall generator: " << wall_generator);
+
+    const DynamicPrintConfig regular_config = wipe_config(
+        wall_generator, false, "50%", "10%", false, "1", "inner wall/outer wall", true, "15%");
+    const DynamicPrintConfig inward_config = wipe_config(
+        wall_generator, true, "50%", "10%", false, "1", "inner wall/outer wall", true, "15%");
+    const std::vector<Vec2d> regular = wipe_destinations(
+        slice({make_cube(10., 10., 1.)}, regular_config));
+    const std::vector<Vec2d> inward = wipe_destinations(
+        slice({make_cube(10., 10., 1.)}, inward_config));
+
+    REQUIRE_FALSE(regular.empty());
+    REQUIRE_FALSE(inward.empty());
+    REQUIRE(trajectories_differ(regular, inward));
+}
+
+TEST_CASE("Inward wipe is not applied before the adjacent wall is printed", "[Wipe][Regression]")
+{
+    const char *wall_generator = GENERATE("classic", "arachne");
+    INFO("wall generator: " << wall_generator);
+
+    const std::vector<Vec2d> regular = wipe_destinations(
+        slice({make_cube(10., 10., 1.)}, wipe_config(
+            wall_generator, false, "50%", "10%", false, "2", "outer wall/inner wall")));
+    const std::vector<Vec2d> inward = wipe_destinations(
+        slice({make_cube(10., 10., 1.)}, wipe_config(
+            wall_generator, true, "50%", "10%", false, "2", "outer wall/inner wall")));
+
+    REQUIRE_FALSE(regular.empty());
+    REQUIRE_FALSE(trajectories_differ(regular, inward));
+}
+
+TEST_CASE("Wipe on loops preserves the corner move with inward wipe disabled", "[Wipe][Regression]")
+{
+    const char *wall_generator = GENERATE("classic", "arachne");
+    const char *nozzle_diameter = GENERATE("0.4", "0.8");
+    const char *comments = GENERATE("0", "1");
+    CAPTURE(comments);
+    INFO("wall generator: " << wall_generator << ", nozzle diameter: " << nozzle_diameter);
+    // A closed square gives a 90-degree material-side corner at the seam.
+    DynamicPrintConfig config = wipe_config(wall_generator, false, "50%", "0", true);
+    config.set_deserialize_strict({{"nozzle_diameter", nozzle_diameter}, {"seam_position", "nearest"},
+                                   {"gcode_comments", comments}});
+    const std::string output = slice({make_cube(10., 10., 1.)}, config);
+    const auto &role_tag = GCodeProcessor::reserved_tag(GCodeProcessor::ETags::Role);
+    const auto &wipe_tag = GCodeProcessor::reserved_tag(GCodeProcessor::ETags::Wipe_Start);
+    ExtrusionRole role = erNone;
+    std::vector<Vec2d> loop;
+    bool after_extrusion = false;
+    size_t moves = 0;
+    GCodeReader parser;
+    parser.apply_config(config);
+    parser.parse_buffer(output, [&](GCodeReader &self, const GCodeReader::GCodeLine &line) {
+        if (line.comment().find(role_tag) == 0) {
+            role = ExtrusionEntity::string_to_role(line.comment().substr(role_tag.size()));
+            loop.clear();
+            after_extrusion = false;
+        }
+        if (line.comment().find(wipe_tag) == 0)
+            after_extrusion = false;
+        if (role != erExternalPerimeter)
+            return;
+        if (line.extruding(self) && line.dist_XY(self) > EPSILON) {
+            if (loop.empty())
+                loop.emplace_back(self.x(), self.y());
+            loop.emplace_back(line.new_X(self), line.new_Y(self));
+            after_extrusion = true;
+            return;
+        }
+        // The loop move is the first non-extruding XY move after the external
+        // wall and before the reserved wipe marker, regardless of comment text.
+        if (!after_extrusion || line.dist_XY(self) <= EPSILON)
+            return;
+        after_extrusion = false;
+
+        ++moves;
+        INFO("layer Z: " << self.z());
+        REQUIRE(loop.size() >= 4);
+        const Vec2d seam = loop.front();
+        REQUIRE_THAT((loop.back() - seam).norm(), Catch::Matchers::WithinAbs(0., 0.003));
+        const Vec2d outgoing = (loop[1] - seam).normalized();
+        const Vec2d into_corner = (loop[loop.size() - 2] - seam).normalized();
+        REQUIRE_THAT(outgoing.dot(into_corner), Catch::Matchers::WithinAbs(0., 0.01));
+        const Vec2d move = Vec2d(line.new_X(self), line.new_Y(self)) - seam;
+        // The legacy corner move is 20% of the nozzle diameter, turned 30 degrees
+        // from the outgoing edge into the square. Check both components independently.
+        const double distance = 0.2 * std::stod(nozzle_diameter);
+        CHECK_THAT(move.dot(outgoing), Catch::Matchers::WithinAbs(distance * std::sqrt(3.) / 2., 0.003));
+        CHECK_THAT(move.dot(into_corner), Catch::Matchers::WithinAbs(distance / 2., 0.003));
+    });
+    REQUIRE(moves == 5);
+}
+
+TEST_CASE("Inward wipe remains valid after wipe on loops moves the nozzle", "[Wipe][Regression]")
+{
+    const char *wall_generator = GENERATE("classic", "arachne");
+    const char *comments = GENERATE("0", "1");
+    CAPTURE(comments);
+    INFO("wall generator: " << wall_generator);
+
+    DynamicPrintConfig config = wipe_config(wall_generator, false, "50%", "10%", true);
+    config.set_deserialize_strict({{"gcode_comments", comments}});
+    const std::string loop_move = slice({make_cube(10., 10., 1.)}, config);
+    config.set_deserialize_strict({{"wipe_inward", "1"}});
+    const std::string combined = slice({make_cube(10., 10., 1.)}, config);
+    config.set_deserialize_strict({{"wipe_on_loops", "0"}});
+    const std::string inward_only = slice({make_cube(10., 10., 1.)}, config);
+
+    for (const std::string *output : {&loop_move, &combined}) {
+        INFO("wipe_inward: " << (output == &combined));
+        std::map<double, std::vector<Vec2d>> loop_moves_by_layer;
+        const auto &role_tag = GCodeProcessor::reserved_tag(GCodeProcessor::ETags::Role);
+        const auto &wipe_tag = GCodeProcessor::reserved_tag(GCodeProcessor::ETags::Wipe_Start);
+        ExtrusionRole role = erNone;
+        bool after_extrusion = false;
+        GCodeReader parser;
+        parser.apply_config(config);
+        parser.parse_buffer(*output, [&](GCodeReader &self, const GCodeReader::GCodeLine &line) {
+            if (line.comment().find(role_tag) == 0) {
+                role = ExtrusionEntity::string_to_role(line.comment().substr(role_tag.size()));
+                after_extrusion = false;
+            }
+            if (line.comment().find(wipe_tag) == 0)
+                after_extrusion = false;
+            if (role != erExternalPerimeter || line.dist_XY(self) <= EPSILON)
+                return;
+            if (line.extruding(self)) {
+                after_extrusion = true;
+            } else if (after_extrusion) {
+                loop_moves_by_layer[line.new_Z(self)].emplace_back(line.new_X(self), line.new_Y(self));
+                after_extrusion = false;
+            }
+        });
+
+        // The 1 mm cube at 0.2 mm layer height has one external loop on each of five layers.
+        const auto trajectories = wipe_trajectories(*output);
+        REQUIRE(loop_moves_by_layer.size() == 5);
+        for (size_t layer = 1; layer <= 5; ++layer) {
+            const double z = layer * 0.2;
+            const auto moves = std::find_if(loop_moves_by_layer.begin(), loop_moves_by_layer.end(),
+                [z](const auto &entry) { return std::abs(entry.first - z) < 0.001; });
+            REQUIRE(moves != loop_moves_by_layer.end());
+            REQUIRE(moves->second.size() == 1);
+            const auto wipe = std::find_if(trajectories.begin(), trajectories.end(), [&](const WipeTrajectory &trajectory) {
+                return std::abs(trajectory.z - z) < 0.001 &&
+                       (trajectory.start - moves->second.front()).norm() < 0.001;
+            });
+            REQUIRE(wipe != trajectories.end());
+            // The configured 2 mm wipe must be measured from the inward move's
+            // endpoint, including when wipe_inward is off (set_last_pos regression).
+            CHECK_THAT(trajectory_length(*wipe), Catch::Matchers::WithinAbs(2., 0.003));
+        }
+    }
+
+    const std::vector<WipeTrajectory> combined_trajectories = wipe_trajectories(combined);
+    const std::vector<WipeTrajectory> inward_trajectories = wipe_trajectories(inward_only);
+    REQUIRE_FALSE(combined_trajectories.empty());
+    REQUIRE(combined_trajectories.size() == inward_trajectories.size());
+    REQUIRE(trajectories_differ(wipe_destinations(combined), wipe_destinations(loop_move)));
+
+    bool start_changed = false;
+    for (size_t i = 0; i < combined_trajectories.size(); ++i) {
+        start_changed = start_changed ||
+            (combined_trajectories[i].start - inward_trajectories[i].start).norm() > 0.01;
+        REQUIRE_THAT(trajectory_length(combined_trajectories[i]),
+                     Catch::Matchers::WithinAbs(trajectory_length(inward_trajectories[i]), 0.01));
+    }
+    REQUIRE(start_changed);
+}

tests/fff_print/test_wipe_tower.cpp

@@ -152,6 +152,8 @@ static DynamicPrintConfig wipe_tower_toolchange_config(const std::string &gcode_
         { "outer_wall_filament_id",     2 },
         { "inner_wall_filament_id",     2 },
         { "enable_prime_tower",         true },
+        { "wipe_tower_x",               50 }, // inside the 200x200 test bed
+        { "wipe_tower_y",               50 }, // (the default y, 220, is not)
         { "layer_height",               0.3 },
         { "gcode_flavor",               gcode_flavor },
     });
@@ -182,3 +184,148 @@ TEST_CASE("The wipe tower's toolchange planner flush follows the gcode flavor",
         CHECK_THAT(tower, !Catch::Matchers::ContainsSubstring(unexpected));
     }
 }
+
+// What Print feeds the shared estimate. The libslic3r WipeTowerEstimate cases cannot see this:
+// they call the estimator directly. The estimate counts the filaments the print really uses,
+// so the two-filament shape gives the outer wall the second one.
+static DynamicPrintConfig tower_estimate_config(const char *wall_type, unsigned int filaments = 2)
+{
+    // 100 mm3 per purge on a 50 mm wide tower: one purge is 100/(layer_height * 50) of depth.
+    return multifilament_config(filaments, {
+        { "outer_wall_filament_id",         filaments == 2 ? "2" : "1" },
+        { "enable_prime_tower",             "1"       },
+        { "wipe_tower_wall_type",           wall_type },
+        { "prime_tower_width",              "50"      },
+        { "prime_volume",                   "100"     },
+        { "prime_tower_infill_gap",         "100%"    },
+        { "prime_tower_brim_width",         "3"       },
+        { "purge_in_prime_tower",           "0"       },
+        { "single_extruder_multi_material", "0"       },
+        { "timelapse_type",                 "0"       },
+        { "layer_height",                   "0.2"     },
+        { "enable_wrapping_detection",      "0"       },
+        { "raft_layers",                    "0"       } });
+}
+
+TEST_CASE("The tower is sized for the thinnest layer any object on the plate is sliced at", "[WipeTower]")
+{
+    // The tower has to survive its thinnest layer, so an override finer than the preset drives
+    // the estimate even on the second object. Two 20 mm cubes, the second at 0.1 mm.
+    const DynamicPrintConfig config = tower_estimate_config("rectangle");
+    const std::vector<std::vector<ConfigBase::SetDeserializeItem>> overrides = {
+        {}, { { "layer_height", "0.1" } } };
+
+    Print print;
+    Model model;
+    init_print({ cube(20), cube(20) }, print, model, config, &overrides);
+
+    // One purge at 0.1 mm: 100 / (0.1 * 50) = 20 mm, above the 20 mm-tall tower's stability
+    // floor. At the preset's 0.2 mm it would be half that, so the two are easy to tell apart.
+    const float floor_20mm = WipeTower::get_limit_depth_by_height(20.f);
+    REQUIRE(floor_20mm < 10.f);
+    CHECK_THAT(print.wipe_tower_data(2).depth, Catch::Matchers::WithinAbs(20., 1e-4));
+}
+
+TEST_CASE("Validation is given the tower's effective width, not the configured one", "[WipeTower]")
+{
+    // A rib wall squares the tower, so its width is its depth. Validation reads this rather
+    // than re-deriving the rule from the wall type.
+    Print print;
+    Model model;
+
+    SECTION("a rectangle wall keeps the configured width") {
+        const DynamicPrintConfig config = tower_estimate_config("rectangle");
+        init_print({ cube(20) }, print, model, config);
+        const WipeTowerData &data = print.wipe_tower_data(2);
+        CHECK_THAT(data.width, Catch::Matchers::WithinAbs(50., 1e-4));
+        CHECK(data.depth < data.width);
+    }
+
+    SECTION("a rib wall reports the squared footprint") {
+        const DynamicPrintConfig config = tower_estimate_config("rib");
+        init_print({ cube(20) }, print, model, config);
+        const WipeTowerData &data = print.wipe_tower_data(2);
+        CHECK_THAT(data.width, Catch::Matchers::WithinAbs(data.depth, 1e-4));
+        CHECK(data.width > 0.f);
+    }
+}
+
+TEST_CASE("Generating the tower keeps its reported width current", "[WipeTower]")
+{
+    // width is handed out after the slice, so leaving it at the estimate reports a zero-width
+    // tower to every post-generation consumer.
+    const DynamicPrintConfig config = wipe_tower_toolchange_config("marlin");
+    Print print;
+    Model model;
+    init_print({ cube(10) }, print, model, config);
+    print.apply(model, config);
+    REQUIRE(print.wipe_tower_data(2).width > 0.f);
+
+    print.process();
+    REQUIRE(print.is_step_done(psWipeTower));
+    const WipeTowerData &data = print.wipe_tower_data();
+    // A width the generator never wrote reads as zero. A rib wall squares the tower, so the
+    // generated width is the body square: under the configured 50 mm, and inside the depth.
+    CHECK(data.width > 0.f);
+    CHECK(data.width < 50.f);
+    CHECK(data.width <= data.depth + EPSILON);
+}
+
+TEST_CASE("A single-filament plate reserves a tower only when one is actually printed", "[WipeTower]")
+{
+    // The estimate has to answer this the way Print::apply does: reporting no tower for one
+    // that is built collapses the validation hull to a point, and reporting one for a tower
+    // that is not built takes that bed area away from the arranger and draws a preview box
+    // over nothing.
+    Print print;
+    Model model;
+
+    SECTION("no tool change and nothing else that prints one") {
+        const DynamicPrintConfig config = tower_estimate_config("rib", 1);
+        init_print({ cube(20) }, print, model, config);
+        REQUIRE_FALSE(print.has_wipe_tower());
+        CHECK_THAT(print.wipe_tower_data(1).depth, Catch::Matchers::WithinAbs(0., 1e-6));
+    }
+
+    // A raft puts the tower on every layer below the object, but only where there is a tower:
+    // Print::apply runs normalize_fdm_2, which clears enable_prime_tower for a plate that
+    // purges one filament and has neither smooth timelapse nor wrapping detection on.
+    SECTION("a raft alone does not print one") {
+        DynamicPrintConfig config = tower_estimate_config("rib", 1);
+        config.set_deserialize_strict({ { "raft_layers", "3" } });
+        init_print({ cube(20) }, print, model, config);
+        REQUIRE_FALSE(print.config().enable_prime_tower.value);
+        REQUIRE_FALSE(print.has_wipe_tower());
+        CHECK_THAT(print.wipe_tower_data(1).depth, Catch::Matchers::WithinAbs(0., 1e-6));
+    }
+
+    SECTION("smooth timelapse prints one, and keeps enable_prime_tower on") {
+        DynamicPrintConfig config = tower_estimate_config("rib", 1);
+        config.set_deserialize_strict({ { "timelapse_type", "1" } });
+        init_print({ cube(20) }, print, model, config);
+        REQUIRE(print.has_wipe_tower());
+        CHECK(print.wipe_tower_data(1).depth > 0.f);
+    }
+}
+
+TEST_CASE("A tower printed without a tool change is still validated against the bed", "[WipeTower]")
+{
+    // Wrapping detection prints a tower on a plate that purges one filament. Neither the old
+    // estimate (which read the wall type and smooth timelapse) nor the old containment gate (the
+    // filament count or smooth timelapse) knew about it, so between them that tower was never
+    // checked against the bed.
+    Print print;
+    Model model;
+    DynamicPrintConfig config = tower_estimate_config("rectangle", 1);
+    // Relative E without a per-layer G92 is rejected before the tower is ever looked at, and
+    // has_wipe_tower() wants a real exclusion polygon before it honours wrapping detection.
+    config.set_deserialize_strict({ { "enable_wrapping_detection", "1" },
+                                    { "wrapping_exclude_area", "180x180,190x180,190x190,180x190" },
+                                    { "wipe_tower_x", "500" }, { "wipe_tower_y", "500" },                                    { "use_relative_e_distances", "0" } });
+
+    init_print({ cube(20) }, print, model, config);
+    REQUIRE(print.extruders(true).size() == 1);
+    REQUIRE(print.has_wipe_tower());
+    CHECK(print.wipe_tower_data(1).depth > 0.f);
+    CHECK_THAT(print.validate().string, Catch::Matchers::ContainsSubstring("printable area"));
+}

tests/libslic3r/CMakeLists.txt

@@ -19,6 +19,7 @@ add_executable(${_TEST_NAME}_tests
     test_preset_setting_id.cpp
     test_preset_diff.cpp
     test_vendor_cache.cpp
+    test_preset_options.cpp
     test_elephant_foot_compensation.cpp
     test_fill_corner_smoothing.cpp
     test_filament_mixer.cpp
@@ -29,16 +30,21 @@ add_executable(${_TEST_NAME}_tests
     test_polygon.cpp
     test_mutable_polygon.cpp
     test_mutable_priority_queue.cpp
+    test_minimum_spanning_tree.cpp
     test_nozzle_volume_type.cpp
     test_step.cpp
     test_stl.cpp
     test_triangle_selector.cpp
     test_meshboolean.cpp
     test_marchingsquares.cpp
+    test_lay_on_face.cpp
     test_model.cpp
     test_utils.cpp
     test_timeutils.cpp
     test_voronoi.cpp
+    test_wipe_tower_estimate.cpp
+    test_wipe_tower.cpp
+    test_wipe_path.cpp
     test_optimizers.cpp
     test_ordering_strategies.cpp
     # test_png_io.cpp

tests/libslic3r/test_3mf.cpp

@@ -1,6 +1,5 @@
 
 #include "libslic3r/Model.hpp"
-#include "libslic3r/TriangleSelector.hpp"
 #include "libslic3r/Format/3mf.hpp"
 #include "libslic3r/Format/bbs_3mf.hpp"
 #include "libslic3r/Format/STL.hpp"
@@ -11,9 +10,12 @@
 #include "libslic3r/Preset.hpp"
 #include "libslic3r/MultiNozzleUtils.hpp"
 #include "libslic3r/ProjectTask.hpp"
+#include "libslic3r/PublishSettings.hpp"
 
 #include "test_utils.hpp"
 
+#include <nlohmann/json.hpp>
+
 #include <boost/filesystem/operations.hpp>
 #include <boost/algorithm/string/predicate.hpp>
 #include <algorithm>
@@ -733,7 +735,6 @@ SCENARIO("Nozzle-group metadata .3mf round-trip", "[3mf][MultiNozzle]") {
     }
 }
 
-
 // A mixed-color filament occupies an ordinary filament slot, and painting with it stores an
 // ordinary extruder state: a project saved by BambuStudio encodes filament 5 of a 5-slot setup
 // as paint state 5, with the mix described by the parallel filament_mixed_* project arrays.
@@ -824,3 +825,639 @@ SCENARIO("Mixed-color filament setup and painting round-trip through a .3mf", "[
         }
     }
 }
+// Locks the serialization contract of the "Publish" metadata: the orca_published flag and the
+// orca_published_keys JSON array in model.model_info->metadata_items must survive a store_bbs_3mf ->
+// load_bbs_3mf round-trip unchanged. (The full preset-preservation behavior is exercised
+// headlessly in test_preset_bundle_loading.cpp.)
+SCENARIO("Published 3MF round-trips the published flag and published_keys metadata", "[3mf]") {
+    GIVEN("a model carrying published metadata") {
+        Model model;
+        std::string src_file = std::string(TEST_DATA_DIR) + "/test_3mf/Prusa.stl";
+        REQUIRE(load_stl(src_file.c_str(), &model));
+        model.add_default_instances();
+
+        model.model_info = std::make_shared<ModelInfo>();
+        model.model_info->metadata_items[ORCA_PUBLISHED_TAG]      = "1";
+        model.model_info->metadata_items[ORCA_PUBLISHED_KEYS_TAG] = R"(["layer_height","wall_thickness"])";
+
+        // store_bbs_3mf stages project_settings.config through the model's backup path; point
+        // it at a writable temp dir (the default lives under a read-only root in CI).
+        ScopedTemporaryDir backup_dir("orca_pub");
+        model.set_backup_path(backup_dir.string());
+
+        WHEN("stored to and reloaded from a .3mf") {
+            ScopedTemporaryFile temp(".3mf");
+            const std::string test_file = temp.string();
+
+            DynamicPrintConfig config = DynamicPrintConfig::full_print_config();
+            StoreParams store_params;
+            store_params.path    = test_file.c_str();
+            store_params.model   = &model;
+            store_params.config  = &config;
+            store_params.strategy = SaveStrategy::Zip64 | SaveStrategy::Silence;
+            REQUIRE(store_bbs_3mf(store_params));
+
+            Model dst_model;
+            DynamicPrintConfig dst_config;
+            ConfigSubstitutionContext ctxt{ ForwardCompatibilitySubstitutionRule::Enable };
+            PlateDataPtrs        dst_plates;
+            std::vector<Preset*> project_presets;
+            bool   is_bbl_3mf = false, is_orca_3mf = false;
+            Semver file_version;
+            bool loaded = load_bbs_3mf(test_file.c_str(), &dst_config, &ctxt, &dst_model, &dst_plates,
+                                       &project_presets, &is_bbl_3mf, &is_orca_3mf, &file_version, nullptr,
+                                       LoadStrategy::LoadModel | LoadStrategy::LoadConfig);
+            THEN("the published metadata round-trips unchanged") {
+                REQUIRE(loaded);
+                REQUIRE(dst_model.model_info != nullptr);
+                REQUIRE(dst_model.model_info->metadata_items[ORCA_PUBLISHED_TAG] == "1");
+                REQUIRE(dst_model.model_info->metadata_items[ORCA_PUBLISHED_KEYS_TAG] == R"(["layer_height","wall_thickness"])");
+
+                // The orca_published_keys value is a JSON array of setting keys; it must parse back to
+                // the same keys that were selected.
+                nlohmann::json keys = nlohmann::json::parse(dst_model.model_info->metadata_items[ORCA_PUBLISHED_KEYS_TAG]);
+                REQUIRE(keys.is_array());
+                REQUIRE(keys.size() == 2);
+                REQUIRE(keys[0] == "layer_height");
+                REQUIRE(keys[1] == "wall_thickness");
+            }
+            release_PlateData_list(dst_plates);
+        }
+    }
+}
+
+// A normal 3MF (no Publish metadata) must load identically: the loader must not fabricate a
+// "orca_published" flag or orca_published_keys for files that never carried them.
+SCENARIO("Legacy 3MF without published metadata loads unchanged", "[3mf]") {
+    GIVEN("a model without any published metadata") {
+        Model model;
+        std::string src_file = std::string(TEST_DATA_DIR) + "/test_3mf/Prusa.stl";
+        REQUIRE(load_stl(src_file.c_str(), &model));
+        model.add_default_instances();
+
+        ScopedTemporaryDir backup_dir("orca_legacy");
+        model.set_backup_path(backup_dir.string());
+
+        WHEN("stored to and reloaded from a .3mf") {
+            ScopedTemporaryFile temp(".3mf");
+            const std::string test_file = temp.string();
+
+            DynamicPrintConfig config = DynamicPrintConfig::full_print_config();
+            StoreParams store_params;
+            store_params.path    = test_file.c_str();
+            store_params.model   = &model;
+            store_params.config  = &config;
+            store_params.strategy = SaveStrategy::Zip64 | SaveStrategy::Silence;
+            REQUIRE(store_bbs_3mf(store_params));
+
+            Model dst_model;
+            DynamicPrintConfig dst_config;
+            ConfigSubstitutionContext ctxt{ ForwardCompatibilitySubstitutionRule::Enable };
+            PlateDataPtrs        dst_plates;
+            std::vector<Preset*> project_presets;
+            bool   is_bbl_3mf = false, is_orca_3mf = false;
+            Semver file_version;
+            bool loaded = load_bbs_3mf(test_file.c_str(), &dst_config, &ctxt, &dst_model, &dst_plates,
+                                       &project_presets, &is_bbl_3mf, &is_orca_3mf, &file_version, nullptr,
+                                       LoadStrategy::LoadModel | LoadStrategy::LoadConfig);
+            THEN("no published key is fabricated") {
+                REQUIRE(loaded);
+                REQUIRE(dst_model.model_info != nullptr);
+                REQUIRE(dst_model.model_info->metadata_items.count(ORCA_PUBLISHED_TAG) == 0);
+                REQUIRE(dst_model.model_info->metadata_items.count(ORCA_PUBLISHED_KEYS_TAG) == 0);
+            }
+            release_PlateData_list(dst_plates);
+        }
+    }
+}
+
+// Locks the serialization contract of the orca_published_material_keys metadata: the per-entry JSON
+// must survive a store_bbs_3mf -> load_bbs_3mf round-trip verbatim, exactly like orca_published_keys.
+SCENARIO("Published 3MF round-trips the published_material_keys metadata", "[3mf]") {
+    GIVEN("a model carrying published material keys metadata") {
+        Model model;
+        std::string src_file = std::string(TEST_DATA_DIR) + "/test_3mf/Prusa.stl";
+        REQUIRE(load_stl(src_file.c_str(), &model));
+        model.add_default_instances();
+
+        const std::string material_keys_json =
+            R"([{"material":{"filament_type":"PLA","filament_vendor":"Generic","filament_id":"GFL99"},"slot":0,"keys":["filament_retraction_length","filament_z_hop"]}])";
+
+        model.model_info = std::make_shared<ModelInfo>();
+        model.model_info->metadata_items[ORCA_PUBLISHED_MATERIAL_TAG] = material_keys_json;
+
+        ScopedTemporaryDir backup_dir("orca_pub_mat");
+        model.set_backup_path(backup_dir.string());
+
+        WHEN("stored to and reloaded from a .3mf") {
+            ScopedTemporaryFile temp(".3mf");
+            const std::string test_file = temp.string();
+
+            DynamicPrintConfig config = DynamicPrintConfig::full_print_config();
+            StoreParams store_params;
+            store_params.path    = test_file.c_str();
+            store_params.model   = &model;
+            store_params.config  = &config;
+            store_params.strategy = SaveStrategy::Zip64 | SaveStrategy::Silence;
+            REQUIRE(store_bbs_3mf(store_params));
+
+            Model dst_model;
+            DynamicPrintConfig dst_config;
+            ConfigSubstitutionContext ctxt{ ForwardCompatibilitySubstitutionRule::Enable };
+            PlateDataPtrs        dst_plates;
+            std::vector<Preset*> project_presets;
+            bool   is_bbl_3mf = false, is_orca_3mf = false;
+            Semver file_version;
+            bool loaded = load_bbs_3mf(test_file.c_str(), &dst_config, &ctxt, &dst_model, &dst_plates,
+                                       &project_presets, &is_bbl_3mf, &is_orca_3mf, &file_version, nullptr,
+                                       LoadStrategy::LoadModel | LoadStrategy::LoadConfig);
+            THEN("the published material keys metadata round-trips unchanged") {
+                REQUIRE(loaded);
+                REQUIRE(dst_model.model_info != nullptr);
+                REQUIRE(dst_model.model_info->metadata_items[ORCA_PUBLISHED_MATERIAL_TAG] == material_keys_json);
+
+                // The value must parse back to one material entry carrying the nested identity
+                // object, the author slot ordinal and the key list.
+                nlohmann::json entries = nlohmann::json::parse(material_keys_json);
+                REQUIRE(entries.is_array());
+                REQUIRE(entries.size() == 1);
+                REQUIRE(entries[0]["material"]["filament_type"] == "PLA");
+                REQUIRE(entries[0]["material"]["filament_vendor"] == "Generic");
+                REQUIRE(entries[0]["material"]["filament_id"] == "GFL99");
+                REQUIRE(entries[0]["slot"] == 0);
+                REQUIRE(entries[0]["keys"].is_array());
+                REQUIRE(entries[0]["keys"].size() == 2);
+                REQUIRE(entries[0]["keys"][0] == "filament_retraction_length");
+            }
+            release_PlateData_list(dst_plates);
+        }
+    }
+}
+
+SCENARIO("Minimal published 3MF omits project config, preset dumps and slicer tags", "[3mf]") {
+    GIVEN("a multi-instance model carrying published metadata and a published_config payload") {
+        Model model;
+        std::string src_file = std::string(TEST_DATA_DIR) + "/test_3mf/Prusa.stl";
+        REQUIRE(load_stl(src_file.c_str(), &model));
+        model.add_default_instances();
+        // A second instance: tag-less third-party files get their multi-instance objects split,
+        // published files must not (the loader recognizes them by their metadata).
+        model.objects.front()->add_instance();
+
+        DynamicPrintConfig full_cfg = DynamicPrintConfig::full_print_config();
+        full_cfg.set_key_value("layer_height", new ConfigOptionFloat(0.24));
+        full_cfg.set_key_value("retraction_length", new ConfigOptionFloats({ 1.2 }));
+
+        const std::vector<std::string> published_keys = { "layer_height", "retraction_length" };
+        const std::vector<PublishedMaterialEntry> material_keys = {
+            { "PLA", "Generic", "GFL99", "", "Generic PLA", 0, { "filament_retraction_length" } }
+        };
+
+        // The payload builder keeps the published and identity keys and drops everything else.
+        DynamicPrintConfig filtered_cfg = filter_published_config(full_cfg, published_keys, material_keys);
+        REQUIRE(filtered_cfg.option("layer_height") != nullptr);
+        REQUIRE(filtered_cfg.option("retraction_length") != nullptr);
+        REQUIRE(filtered_cfg.option("filament_colour") != nullptr);
+        REQUIRE(filtered_cfg.option("filament_type") != nullptr);
+        REQUIRE(filtered_cfg.option("wipe_tower_x") != nullptr);
+        REQUIRE(filtered_cfg.option("sparse_infill_density") == nullptr);
+        REQUIRE(filtered_cfg.option("machine_start_gcode") == nullptr);
+
+        // Serialize the payload exactly like export_published_3mf does.
+        std::string payload;
+        for (const std::string &key : filtered_cfg.keys())
+            payload += key + " = " + filtered_cfg.opt_serialize(key) + "\n";
+
+        model.model_info = std::make_shared<ModelInfo>();
+        model.model_info->metadata_items[ORCA_PUBLISHED_TAG]      = "1";
+        model.model_info->metadata_items[ORCA_PUBLISHED_KEYS_TAG] = R"(["layer_height","retraction_length"])";
+        model.model_info->metadata_items[ORCA_PUBLISHED_CONFIG_TAG] = payload;
+
+        ScopedTemporaryDir backup_dir("orca_min_pub");
+        model.set_backup_path(backup_dir.string());
+
+        WHEN("stored using SaveStrategy::MinimalPublished and reloaded") {
+            ScopedTemporaryFile temp(".3mf");
+            const std::string test_file = temp.string();
+
+            // Create a fake project preset to verify MinimalPublished omits it.
+            Preset preset(Preset::TYPE_PRINT, "TestPrintPreset");
+            preset.config = full_cfg;
+            std::vector<Preset*> project_presets = { &preset };
+
+            StoreParams store_params;
+            store_params.path    = test_file.c_str();
+            store_params.model   = &model;
+            store_params.config  = &filtered_cfg;
+            store_params.project_presets = project_presets;
+            store_params.strategy = SaveStrategy::Zip64 | SaveStrategy::Silence | SaveStrategy::MinimalPublished;
+            REQUIRE(store_bbs_3mf(store_params));
+
+            Model dst_model;
+            ScopedTemporaryDir loaded_backup_dir("orca_min_pub_loaded");
+            dst_model.set_backup_path(loaded_backup_dir.string());
+            DynamicPrintConfig dst_config;
+            ConfigSubstitutionContext ctxt{ ForwardCompatibilitySubstitutionRule::Enable };
+            PlateDataPtrs        dst_plates;
+            std::vector<Preset*> loaded_presets;
+            bool   is_bbl_3mf = false, is_orca_3mf = false;
+            Semver file_version;
+            bool loaded = load_bbs_3mf(test_file.c_str(), &dst_config, &ctxt, &dst_model, &dst_plates,
+                                       &loaded_presets, &is_bbl_3mf, &is_orca_3mf, &file_version, nullptr,
+                                       LoadStrategy::LoadModel | LoadStrategy::LoadConfig);
+            THEN("the 3MF loads without project config or embedded presets") {
+                REQUIRE(loaded);
+                REQUIRE(dst_config.empty());
+                REQUIRE(loaded_presets.empty());
+            }
+            THEN("the file carries no slicer tags and classifies as a generic 3MF") {
+                REQUIRE_FALSE(is_bbl_3mf);
+                REQUIRE_FALSE(is_orca_3mf);
+                // No Application / OrcaSlicer tag: old receivers import the geometry silently
+                // instead of showing a baked-in, wrong "old version" popup.
+                REQUIRE_FALSE(file_version.valid());
+            }
+            THEN("the geometry keeps BBS-grade handling: instances are not split") {
+                REQUIRE(dst_model.objects.size() == 1);
+                REQUIRE(dst_model.objects.front()->instances.size() == 2);
+            }
+            THEN("the published metadata and payload round-trip unchanged") {
+                REQUIRE(dst_model.model_info != nullptr);
+                REQUIRE(dst_model.model_info->metadata_items[ORCA_PUBLISHED_TAG] == "1");
+                REQUIRE(dst_model.model_info->metadata_items[ORCA_PUBLISHED_KEYS_TAG] == R"(["layer_height","retraction_length"])");
+                REQUIRE(dst_model.model_info->metadata_items[ORCA_PUBLISHED_CONFIG_TAG] == payload);
+            }
+            THEN("the payload parses back to the published values") {
+                DynamicPrintConfig parsed_payload;
+                parsed_payload.load_from_ini_string(dst_model.model_info->metadata_items[ORCA_PUBLISHED_CONFIG_TAG], ForwardCompatibilitySubstitutionRule::Enable);
+                REQUIRE(parsed_payload.option("layer_height") != nullptr);
+                REQUIRE_THAT(parsed_payload.opt_float("layer_height"), Catch::Matchers::WithinAbs(0.24, 1e-6));
+                REQUIRE(parsed_payload.option("retraction_length") != nullptr);
+                REQUIRE_THAT(parsed_payload.opt<ConfigOptionFloats>("retraction_length")->get_at(0), Catch::Matchers::WithinAbs(1.2, 1e-6));
+            }
+            release_PlateData_list(dst_plates);
+        }
+    }
+}
+
+// A minimal published 3MF must not leak the slicer tags of the source project. The exporter seeds
+// metadata_item_map from the input file's metadata_items, so re-publishing a project opened from a
+// regular Orca/BBS 3MF (the typical remix flow) must strip the Application / OrcaSlicer tags it
+// came with, otherwise old receivers route onto the baked-in "old version" popup.
+SCENARIO("MinimalPublished strips slicer tags carried by the source project", "[3mf]") {
+    GIVEN("a model loaded from a regular Orca/BBS 3MF whose metadata carries the slicer tags") {
+        Model model;
+        std::string src_file = std::string(TEST_DATA_DIR) + "/test_3mf/Prusa.stl";
+        REQUIRE(load_stl(src_file.c_str(), &model));
+        model.add_default_instances();
+
+        model.model_info = std::make_shared<ModelInfo>();
+        model.model_info->metadata_items[ORCA_PUBLISHED_TAG] = "1";
+        model.model_info->metadata_items["Application"]     = "BambuStudio-2.0.0";
+        model.model_info->metadata_items["OrcaSlicer"]      = "2.1.0";
+
+        ScopedTemporaryDir backup_dir("orca_strip_tags");
+        model.set_backup_path(backup_dir.string());
+
+        WHEN("stored using SaveStrategy::MinimalPublished and reloaded") {
+            ScopedTemporaryFile temp(".3mf");
+            const std::string test_file = temp.string();
+
+            DynamicPrintConfig config = DynamicPrintConfig::full_print_config();
+            StoreParams store_params;
+            store_params.path    = test_file.c_str();
+            store_params.model   = &model;
+            store_params.config  = &config;
+            store_params.strategy = SaveStrategy::Zip64 | SaveStrategy::Silence | SaveStrategy::MinimalPublished;
+            REQUIRE(store_bbs_3mf(store_params));
+
+            Model dst_model;
+            DynamicPrintConfig dst_config;
+            ConfigSubstitutionContext ctxt{ ForwardCompatibilitySubstitutionRule::Enable };
+            PlateDataPtrs        dst_plates;
+            std::vector<Preset*> loaded_presets;
+            bool   is_bbl_3mf = false, is_orca_3mf = false;
+            Semver file_version;
+            bool loaded = load_bbs_3mf(test_file.c_str(), &dst_config, &ctxt, &dst_model, &dst_plates,
+                                       &loaded_presets, &is_bbl_3mf, &is_orca_3mf, &file_version, nullptr,
+                                       LoadStrategy::LoadModel | LoadStrategy::LoadConfig);
+            THEN("the source slicer tags are stripped, not carried through") {
+                REQUIRE(loaded);
+                REQUIRE(dst_model.model_info != nullptr);
+                REQUIRE(dst_model.model_info->metadata_items.count("Application") == 0);
+                REQUIRE(dst_model.model_info->metadata_items.count("OrcaSlicer") == 0);
+                // The published marker itself must survive.
+                REQUIRE(dst_model.model_info->metadata_items[ORCA_PUBLISHED_TAG] == "1");
+            }
+            THEN("the file classifies as a generic 3MF without a version popup") {
+                REQUIRE_FALSE(is_bbl_3mf);
+                REQUIRE_FALSE(is_orca_3mf);
+                REQUIRE_FALSE(file_version.valid());
+            }
+            release_PlateData_list(dst_plates);
+        }
+    }
+}
+
+// An entry masks the non-published slots to their defaults so publishing slot 1 never leaks slot
+// 0's value into the file. Both a full entry (the whole-slot key list) and a partial entry (a
+// per-slot key) go through the same masking path in filter_published_config (keys and full_keys
+// are filtered identically), so the two forms are exercised together.
+SCENARIO("Published entries mask the other slots to their defaults", "[3mf]") {
+    const bool full = GENERATE(true, false);
+    GIVEN("a full print configuration with two filament slots") {
+        DynamicPrintConfig full_cfg = DynamicPrintConfig::full_print_config();
+        full_cfg.opt<ConfigOptionFloats>("filament_diameter")->values = { 1.75, 1.75 };
+        full_cfg.opt<ConfigOptionStrings>("filament_colour")->values = { "#111111", "#222222" };
+        // filament_flow_ratio carries a non-empty option default (1.0) of the same type, so the
+        // mask can restore it on the non-published slot.
+        full_cfg.opt<ConfigOptionFloatsNullable>("filament_flow_ratio", true)->values = { 1.02, 0.98 };
+
+        WHEN("filtering with a published entry for slot 1") {
+            PublishedMaterialEntry entry;
+            entry.slot = 1;
+            if (full) {
+                entry.full      = true;
+                entry.full_keys = { "filament_flow_ratio" };
+            } else {
+                entry.keys = { "filament_flow_ratio" };
+            }
+            DynamicPrintConfig filtered_cfg = filter_published_config(full_cfg, {}, { entry });
+
+            THEN("the selected key is present with the author's slot value") {
+                REQUIRE(filtered_cfg.option("filament_flow_ratio") != nullptr);
+                REQUIRE_THAT(filtered_cfg.opt<ConfigOptionFloatsNullable>("filament_flow_ratio")->values[1], Catch::Matchers::WithinAbs(0.98, 1e-6));
+            }
+            THEN("the non-published slot is masked to its default") {
+                REQUIRE_THAT(filtered_cfg.opt<ConfigOptionFloatsNullable>("filament_flow_ratio")->values[0], Catch::Matchers::WithinAbs(1.0, 1e-6));
+            }
+            THEN("the identity keys stay present") {
+                REQUIRE(filtered_cfg.option("filament_colour") != nullptr);
+            }
+        }
+    }
+}
+
+// A key needing slot masking that cannot be masked (no registered option default of the same
+// type) is dropped from the payload entirely instead of shipping the author's whole vector.
+SCENARIO("Unmaskable keys are dropped from the published payload instead of leaking", "[3mf]") {
+    GIVEN("a config carrying a synthetic def-less vector key and a maskable one") {
+        DynamicPrintConfig full_cfg = DynamicPrintConfig::full_print_config();
+        full_cfg.opt<ConfigOptionFloats>("filament_diameter")->values = { 1.75, 1.75 };
+        full_cfg.opt<ConfigOptionStrings>("filament_colour")->values  = { "#111111", "#222222" };
+        // Not a PrintConfig key: print_config_def has no default to mask with.
+        full_cfg.set_key_value("orca_synthetic_setting", new ConfigOptionFloats({ 9.9, 8.8 }));
+        full_cfg.opt<ConfigOptionFloatsNullable>("filament_flow_ratio", true)->values = { 1.02, 0.98 };
+
+        PublishedMaterialEntry partial_entry;
+        partial_entry.slot = 1;
+        partial_entry.keys = { "orca_synthetic_setting", "filament_flow_ratio" };
+
+        WHEN("filtering with a partial entry for slot 1") {
+            DynamicPrintConfig filtered_cfg = filter_published_config(full_cfg, {}, { partial_entry });
+
+            THEN("the unmaskable synthetic key is not published") {
+                REQUIRE(filtered_cfg.option("orca_synthetic_setting") == nullptr);
+            }
+            THEN("the maskable key is present, author slot kept, other slot masked") {
+                REQUIRE(filtered_cfg.opt<ConfigOptionFloatsNullable>("filament_flow_ratio") != nullptr);
+                REQUIRE_THAT(filtered_cfg.opt<ConfigOptionFloatsNullable>("filament_flow_ratio")->values[1], Catch::Matchers::WithinAbs(0.98, 1e-6));
+                REQUIRE_THAT(filtered_cfg.opt<ConfigOptionFloatsNullable>("filament_flow_ratio")->values[0], Catch::Matchers::WithinAbs(1.0, 1e-6));
+            }
+            THEN("the identity keys stay present") {
+                REQUIRE(filtered_cfg.option("filament_colour") != nullptr);
+            }
+        }
+    }
+}
+
+// A per-extruder printer key carrying a "#N" variant (e.g. retraction_length#1) must not serialize
+// every extruder's value: the base is masked to the author's extruder and the other slots are
+// restored to their option default, matching the material-side slot-masking invariant. A bare
+// printer base key (no variant) keeps whole-vector serialization.
+SCENARIO("Published per-extruder printer keys mask the other extruders to their defaults", "[3mf]") {
+    GIVEN("a full print configuration with three extruders carrying per-extruder retraction values") {
+        DynamicPrintConfig full_cfg = DynamicPrintConfig::full_print_config();
+        // Non-default values on the un-selected slots, so a leak is distinguishable from the mask
+        // restoring the option default (retraction_length defaults to {0.8}).
+        full_cfg.opt<ConfigOptionFloats>("retraction_length")->values = { 3.0, 1.2, 4.0 };
+
+        WHEN("filtering with only extruder 1's retraction_length checked") {
+            DynamicPrintConfig filtered_cfg = filter_published_config(full_cfg, { "retraction_length#1" }, {});
+
+            THEN("the author's extruder value survives") {
+                REQUIRE_THAT(filtered_cfg.opt<ConfigOptionFloats>("retraction_length")->values[1], Catch::Matchers::WithinAbs(1.2, 1e-6));
+            }
+            THEN("the other extruders are masked to their default") {
+                REQUIRE_THAT(filtered_cfg.opt<ConfigOptionFloats>("retraction_length")->values[0], Catch::Matchers::WithinAbs(0.8, 1e-6));
+                REQUIRE_THAT(filtered_cfg.opt<ConfigOptionFloats>("retraction_length")->values[2], Catch::Matchers::WithinAbs(0.8, 1e-6));
+            }
+        }
+        WHEN("filtering the bare base key without a '#N' variant") {
+            DynamicPrintConfig filtered_cfg = filter_published_config(full_cfg, { "retraction_length" }, {});
+
+            THEN("the whole vector is serialized unmasked") {
+                REQUIRE_THAT(filtered_cfg.opt<ConfigOptionFloats>("retraction_length")->values[0], Catch::Matchers::WithinAbs(3.0, 1e-6));
+                REQUIRE_THAT(filtered_cfg.opt<ConfigOptionFloats>("retraction_length")->values[1], Catch::Matchers::WithinAbs(1.2, 1e-6));
+                REQUIRE_THAT(filtered_cfg.opt<ConfigOptionFloats>("retraction_length")->values[2], Catch::Matchers::WithinAbs(4.0, 1e-6));
+            }
+        }
+    }
+}
+
+// The extended per-entry fields (full dump list, published type and colour) travel inside the
+// published_material_keys metadata and round-trip unchanged.
+SCENARIO("Published 3MF round-trips the extended material metadata", "[3mf]") {
+    GIVEN("a model carrying extended published material keys metadata") {
+        Model model;
+        std::string src_file = std::string(TEST_DATA_DIR) + "/test_3mf/Prusa.stl";
+        REQUIRE(load_stl(src_file.c_str(), &model));
+        model.add_default_instances();
+
+        const std::string material_keys_json =
+            R"([{"material":{"filament_type":"PLA","filament_vendor":"Generic","filament_id":"GFL99","setting_id":"RFs9eCKYOMUSmvZf","name":"Generic PLA Matte @System"},"slot":1,"keys":[],"full":true,"full_keys":["filament_retraction_length","filament_colour"],"publish_type":true,"type":"PLA","publish_color":false,"color":""}])";
+
+        model.model_info = std::make_shared<ModelInfo>();
+        model.model_info->metadata_items[ORCA_PUBLISHED_MATERIAL_TAG] = material_keys_json;
+
+        ScopedTemporaryDir backup_dir("orca_pub_mat2");
+        model.set_backup_path(backup_dir.string());
+
+        WHEN("stored to and reloaded from a .3mf") {
+            ScopedTemporaryFile temp(".3mf");
+            const std::string test_file = temp.string();
+
+            DynamicPrintConfig config = DynamicPrintConfig::full_print_config();
+            StoreParams store_params;
+            store_params.path     = test_file.c_str();
+            store_params.model    = &model;
+            store_params.config   = &config;
+            store_params.strategy = SaveStrategy::Zip64 | SaveStrategy::Silence;
+            REQUIRE(store_bbs_3mf(store_params));
+
+            Model dst_model;
+            DynamicPrintConfig dst_config;
+            ConfigSubstitutionContext ctxt{ ForwardCompatibilitySubstitutionRule::Enable };
+            PlateDataPtrs        dst_plates;
+            std::vector<Preset*> project_presets;
+            bool   is_bbl_3mf = false, is_orca_3mf = false;
+            Semver file_version;
+            bool loaded = load_bbs_3mf(test_file.c_str(), &dst_config, &ctxt, &dst_model, &dst_plates,
+                                       &project_presets, &is_bbl_3mf, &is_orca_3mf, &file_version, nullptr,
+                                       LoadStrategy::LoadModel | LoadStrategy::LoadConfig);
+            THEN("the extended material metadata round-trips unchanged") {
+                REQUIRE(loaded);
+                REQUIRE(dst_model.model_info != nullptr);
+                REQUIRE(dst_model.model_info->metadata_items[ORCA_PUBLISHED_MATERIAL_TAG] == material_keys_json);
+
+                // The value must parse back with every extended field intact.
+                nlohmann::json entries = nlohmann::json::parse(material_keys_json);
+                REQUIRE(entries.is_array());
+                REQUIRE(entries.size() == 1);
+                REQUIRE(entries[0]["full"].get<bool>() == true);
+                REQUIRE(entries[0]["full_keys"].is_array());
+                REQUIRE(entries[0]["full_keys"].size() == 2);
+                REQUIRE(entries[0]["publish_type"].get<bool>() == true);
+                REQUIRE(entries[0]["type"] == "PLA");
+                REQUIRE(entries[0]["publish_color"].get<bool>() == false);
+            }
+            release_PlateData_list(dst_plates);
+        }
+    }
+}
+
+// A published mixed filament serializes its whole definition (components, ratios, gradient)
+// masked to the author's slot: the mix slot's values survive, the non-published slots reset to
+// their defaults, so a partial publish never leaks another slot's mix data.
+SCENARIO("Published mixed-filament keys are masked to the author's slot", "[3mf]") {
+    GIVEN("a full print configuration with three slots, one of them mixed") {
+        DynamicPrintConfig full_cfg = DynamicPrintConfig::full_print_config();
+        full_cfg.opt<ConfigOptionFloats>("filament_diameter")->values = { 1.75, 1.75, 1.75 };
+        full_cfg.opt<ConfigOptionStrings>("filament_colour")->values  = { "#111111", "#222222", "#333333" };
+        full_cfg.opt<ConfigOptionBools>("filament_is_mixed")->values  = { 0, 0, 1 };
+        full_cfg.opt<ConfigOptionStrings>("filament_mixed_components")->values       = { "", "", "1,2" };
+        full_cfg.opt<ConfigOptionStrings>("filament_mixed_sublayer_ratios")->values   = { "", "", "0.6,0.4" };
+        full_cfg.opt<ConfigOptionBools>("filament_mixed_gradient")->values            = { 0, 0, 1 };
+        full_cfg.opt<ConfigOptionStrings>("filament_mixed_gradient_range")->values    = { "", "", "0.9,0.1" };
+        full_cfg.opt<ConfigOptionStrings>("filament_mixed_gradient_curve")->values    = { "", "", "0,0.1|1,0.9" };
+        full_cfg.opt<ConfigOptionBools>("filament_mixed_gradient_per_part")->values   = { 0, 0, 1 };
+
+        PublishedMaterialEntry mix_entry;
+        mix_entry.slot = 2;
+        mix_entry.keys = {
+            "filament_is_mixed",          "filament_mixed_components",       "filament_mixed_sublayer_ratios",
+            "filament_mixed_gradient",    "filament_mixed_gradient_range",   "filament_mixed_gradient_curve",
+            "filament_mixed_gradient_per_part"
+        };
+
+        WHEN("filtering with a mixed entry for slot 2") {
+            DynamicPrintConfig filtered_cfg = filter_published_config(full_cfg, {}, { mix_entry });
+
+            THEN("the author's mixed slot keeps its definition") {
+                REQUIRE(filtered_cfg.option("filament_is_mixed") != nullptr);
+                REQUIRE(filtered_cfg.opt<ConfigOptionBools>("filament_is_mixed")->values == std::vector<unsigned char>{ 0, 0, 1 });
+                const auto& components = filtered_cfg.opt<ConfigOptionStrings>("filament_mixed_components")->values;
+                REQUIRE(components.size() == 3);
+                CHECK(components[2] == "1,2");
+                CHECK(filtered_cfg.opt<ConfigOptionStrings>("filament_mixed_sublayer_ratios")->values[2] == "0.6,0.4");
+                CHECK(filtered_cfg.opt<ConfigOptionStrings>("filament_mixed_gradient_curve")->values[2] == "0,0.1|1,0.9");
+                CHECK(filtered_cfg.opt<ConfigOptionBools>("filament_mixed_gradient")->values[2]);
+                CHECK(filtered_cfg.opt<ConfigOptionBools>("filament_mixed_gradient_per_part")->values[2]);
+            }
+            THEN("the non-published slots are masked to their defaults") {
+                CHECK(filtered_cfg.opt<ConfigOptionStrings>("filament_mixed_components")->values[0] == "");
+                CHECK(filtered_cfg.opt<ConfigOptionStrings>("filament_mixed_components")->values[1] == "");
+                CHECK(filtered_cfg.opt<ConfigOptionBools>("filament_is_mixed")->values[0] == 0);
+                CHECK(filtered_cfg.opt<ConfigOptionBools>("filament_is_mixed")->values[1] == 0);
+            }
+            THEN("the identity keys stay present") {
+                REQUIRE(filtered_cfg.option("filament_colour") != nullptr);
+            }
+        }
+    }
+}
+
+// The published flag is gated on the exact string "1": any other serialized value means "not
+// published", so a receiver never treats a file as published on a loose truthiness check.
+TEST_CASE("is_published_3mf_flag accepts only the literal \"1\"", "[3mf]") {
+    CHECK(is_published_3mf_flag("1"));
+    CHECK_FALSE(is_published_3mf_flag("0"));
+    CHECK_FALSE(is_published_3mf_flag("false"));
+    CHECK_FALSE(is_published_3mf_flag("true"));
+    CHECK_FALSE(is_published_3mf_flag(""));
+    CHECK_FALSE(is_published_3mf_flag("YES"));
+}
+
+// bbs_3mf_is_published is the lightweight metadata probe used to decide whether a file was
+// produced by the publish feature (GUI "recently published" tracking). It must return true only
+// for a file whose metadata carries the flag set to "1", and false for legacy files and for a
+// file whose flag is present but not "1" (which loads as a normal, non-published 3MF).
+SCENARIO("bbs_3mf_is_published detects only genuinely published 3MFs", "[3mf]") {
+    auto store_model = [](const std::string &path, const std::string &flag_value, const std::string &keys_value) {
+        Model model;
+        std::string src_file = std::string(TEST_DATA_DIR) + "/test_3mf/Prusa.stl";
+        REQUIRE(load_stl(src_file.c_str(), &model));
+        model.add_default_instances();
+        model.model_info = std::make_shared<ModelInfo>();
+        // An empty flag_value means "don't write the flag at all" (a legacy file).
+        if (!flag_value.empty())
+            model.model_info->metadata_items[ORCA_PUBLISHED_TAG] = flag_value;
+        model.model_info->metadata_items[ORCA_PUBLISHED_KEYS_TAG] = keys_value;
+        ScopedTemporaryDir backup_dir("orca_is_pub");
+        model.set_backup_path(backup_dir.string());
+        DynamicPrintConfig config = DynamicPrintConfig::full_print_config();
+        StoreParams store_params;
+        store_params.path     = path.c_str();
+        store_params.model    = &model;
+        store_params.config   = &config;
+        store_params.strategy = SaveStrategy::Zip64 | SaveStrategy::Silence;
+        REQUIRE(store_bbs_3mf(store_params));
+    };
+
+    GIVEN("a minimal published 3MF whose flag is \"1\"") {
+        ScopedTemporaryFile temp(".3mf");
+        store_model(temp.string(), "1", R"(["layer_height"])");
+        WHEN("probed by bbs_3mf_is_published") {
+            THEN("it is recognized as published") {
+                CHECK(bbs_3mf_is_published(temp.string()));
+            }
+        }
+    }
+    GIVEN("a legacy 3MF without any published flag") {
+        ScopedTemporaryFile temp(".3mf");
+        store_model(temp.string(), "", R"(["layer_height"])");
+        WHEN("probed by bbs_3mf_is_published") {
+            THEN("it is not recognized as published") {
+                CHECK_FALSE(bbs_3mf_is_published(temp.string()));
+            }
+        }
+    }
+    GIVEN("a 3MF carrying the flag set to \"0\"") {
+        ScopedTemporaryFile temp(".3mf");
+        store_model(temp.string(), "0", R"(["layer_height"])");
+        WHEN("probed and loaded") {
+            THEN("it is not recognized as published") {
+                CHECK_FALSE(bbs_3mf_is_published(temp.string()));
+            }
+            THEN("it loads as a normal, non-published 3MF") {
+                Model dst_model;
+                DynamicPrintConfig dst_config;
+                ConfigSubstitutionContext ctxt{ ForwardCompatibilitySubstitutionRule::Enable };
+                PlateDataPtrs        dst_plates;
+                std::vector<Preset*> project_presets;
+                bool   is_bbl_3mf = false, is_orca_3mf = false;
+                Semver file_version;
+                REQUIRE(load_bbs_3mf(temp.string().c_str(), &dst_config, &ctxt, &dst_model, &dst_plates,
+                                     &project_presets, &is_bbl_3mf, &is_orca_3mf, &file_version, nullptr,
+                                     LoadStrategy::LoadModel | LoadStrategy::LoadConfig));
+                REQUIRE(dst_model.model_info != nullptr);
+                // The key is present but not "1", so nothing treats the file as published; the
+                // stored keys still round-trip verbatim.
+                REQUIRE(dst_model.model_info->metadata_items[ORCA_PUBLISHED_TAG] == "0");
+                REQUIRE(dst_model.model_info->metadata_items[ORCA_PUBLISHED_KEYS_TAG] == R"(["layer_height"])");
+                release_PlateData_list(dst_plates);
+            }
+        }
+    }
+}
+

tests/libslic3r/test_arrange.cpp

@@ -4,6 +4,8 @@
 #include "libslic3r/BoundingBox.hpp"
 #include "libslic3r/ClipperUtils.hpp"
 #include "libslic3r/ExPolygon.hpp"
+#include "libslic3r/Print.hpp"
+#include "libslic3r/PrintConfig.hpp"
 
 using namespace Slic3r;
 using namespace Slic3r::arrangement;
@@ -24,11 +26,13 @@ ArrangePolygon make_square(coord_t side)
     return ap;
 }
 
-ArrangePolygons squares(int n, double side_mm)
+ArrangePolygons squares(int n, double side_mm, double height_mm = 0.)
 {
     ArrangePolygons items;
-    for (int i = 0; i < n; ++i)
+    for (int i = 0; i < n; ++i) {
         items.emplace_back(make_square(scaled(side_mm)));
+        items.back().height = height_mm;
+    }
     return items;
 }
 
@@ -82,6 +86,38 @@ void require_no_overlap(const ArrangePolygons &items)
     REQUIRE(disjoint(placed_shapes(items)));
 }
 
+// The sequential-print floor is chosen by comparing object height against the nozzle,
+// so the two are defined together and every expectation is derived from them.
+constexpr double NOZZLE_HEIGHT_MM = 2.5;
+constexpr double CLEARANCE_MM     = 30.;
+constexpr double NOZZLE_FLOOR_MM  = MAX_OUTER_NOZZLE_DIAMETER / 2.;
+
+ArrangeParams seq_print_params(coord_t min_dist)
+{
+    ArrangeParams p       = quiet_params(min_dist);
+    p.is_seq_print        = true;
+    p.clearance_radius    = float(CLEARANCE_MM);
+    p.nozzle_height       = float(NOZZLE_HEIGHT_MM);
+    p.object_skirt_offset = 0.f;
+    return p;
+}
+
+// update_selected_items_inflation reads the bed out of the config to cap inflation.
+DynamicPrintConfig bed_config()
+{
+    DynamicPrintConfig c;
+    c.set_key_value("printable_area", new ConfigOptionPoints{{0, 0}, {200, 0}, {200, 200}, {0, 200}});
+    return c;
+}
+
+ArrangePolygons squares_of_heights(const std::vector<double> &heights_mm)
+{
+    ArrangePolygons items;
+    for (double height_mm : heights_mm)
+        items.push_back(squares(1, 20., height_mm).front());
+    return items;
+}
+
 } // namespace
 
 // Prove the overlap check the other tests rely on actually detects overlap.
@@ -222,3 +258,61 @@ TEST_CASE("Arrange aligns the pile to a custom center", "[Arrange]")
         REQUIRE(ap.bed_idx == 0);
     require_no_overlap(items);
 }
+
+TEST_CASE("Sequential print floors the object distance by object height", "[Arrange]")
+{
+    // The only place sequential-print clearance is enforced. The arrange menu offers
+    // no floor of its own, so a stored 0 has to be raised here or not at all.
+    struct Case
+    {
+        std::string         description;
+        std::vector<double> heights;
+        double              skirt_offset_mm;
+        double              expected_floor_mm;
+    };
+
+    auto c = GENERATE(values<Case>({
+        {"objects taller than the nozzle need the full clearance",     {NOZZLE_HEIGHT_MM * 2, NOZZLE_HEIGHT_MM * 2}, 0., CLEARANCE_MM},
+        {"an object exactly at the nozzle height counts as tall",      {NOZZLE_HEIGHT_MM,     NOZZLE_HEIGHT_MM},     0., CLEARANCE_MM},
+        {"one tall object among short ones is enough",                 {NOZZLE_HEIGHT_MM / 2, NOZZLE_HEIGHT_MM * 2}, 0., CLEARANCE_MM},
+        {"objects the nozzle clears keep only the nozzle-width floor", {NOZZLE_HEIGHT_MM / 2, NOZZLE_HEIGHT_MM / 2}, 0., NOZZLE_FLOOR_MM},
+        {"a wide skirt raises the floor for short objects",            {NOZZLE_HEIGHT_MM / 2, NOZZLE_HEIGHT_MM / 2}, 3., 6.},
+    }));
+
+    DYNAMIC_SECTION(c.description)
+    {
+        ArrangePolygons    items = squares_of_heights(c.heights);
+        DynamicPrintConfig cfg   = bed_config();
+        ArrangeParams      p     = seq_print_params(0);
+        p.object_skirt_offset    = float(c.skirt_offset_mm);
+
+        update_selected_items_inflation(items, &cfg, p);
+
+        CHECK(p.min_obj_distance >= scaled(c.expected_floor_mm));
+        CHECK(p.min_obj_distance <= scaled(c.expected_floor_mm + 0.01));
+        // Half each, so a pair ends up a full min_obj_distance apart.
+        CHECK(items.front().inflation == p.min_obj_distance / 2);
+    }
+}
+
+TEST_CASE("Sequential print keeps an object distance already above the floor", "[Arrange]")
+{
+    const coord_t      stored = scaled(CLEARANCE_MM * 2);
+    ArrangePolygons    items  = squares_of_heights({NOZZLE_HEIGHT_MM * 2, NOZZLE_HEIGHT_MM * 2});
+    DynamicPrintConfig cfg    = bed_config();
+    ArrangeParams      p      = seq_print_params(stored);
+
+    update_selected_items_inflation(items, &cfg, p);
+    CHECK(p.min_obj_distance == stored);
+}
+
+TEST_CASE("Layered printing does not floor the object distance", "[Arrange]")
+{
+    ArrangePolygons    items = squares_of_heights({NOZZLE_HEIGHT_MM * 2, NOZZLE_HEIGHT_MM * 2});
+    DynamicPrintConfig cfg   = bed_config();
+    ArrangeParams      p     = seq_print_params(0);
+    p.is_seq_print           = false;
+
+    update_selected_items_inflation(items, &cfg, p);
+    CHECK(p.min_obj_distance == 0);
+}

tests/libslic3r/test_config.cpp

@@ -15,6 +15,8 @@
 #include <boost/nowide/fstream.hpp>
 #include <nlohmann/json.hpp>
 
+#include <sstream>
+
 using namespace Slic3r;
 
 SCENARIO("Generic config validation performs as expected.", "[Config]") {
@@ -488,6 +490,59 @@ TEST_CASE("save_to_json round-trips plugin capability references as strings", "[
     CHECK(reloaded.option<ConfigOptionStrings>("slicing_pipeline_plugin")->values == refs);
 }
 
+TEST_CASE("save_to_json writes the same document to a stream as to a file", "[Config]") {
+    DynamicPrintConfig config;
+    config.set_key_value("layer_height", new ConfigOptionFloat(0.2));
+    config.set_key_value("wall_loops", new ConfigOptionInt(3));
+    config.set_key_value("filament_type", new ConfigOptionStrings({ "PLA", "PETG" }));
+    config.set_key_value("machine_start_gcode", new ConfigOptionString("G28\nG1 Z5"));
+
+    ScopedTemporaryFile tmp(".json");
+    config.save_to_json(tmp.string(), "test_preset", "User", "1.0.0.0");
+    std::string file_contents;
+    {
+        boost::nowide::ifstream ifs(tmp.string());
+        file_contents.assign(std::istreambuf_iterator<char>(ifs), std::istreambuf_iterator<char>());
+    }
+    // The file format: one tab per nesting level and a trailing newline.
+    REQUIRE_FALSE(file_contents.empty());
+    CHECK(file_contents.rfind("{\n\t\"", 0) == 0);
+    CHECK(file_contents.back() == '\n');
+
+    std::ostringstream strict, replaced;
+    config.save_to_json(strict, "test_preset", "User", "1.0.0.0");
+    config.save_to_json(replaced, "test_preset", "User", "1.0.0.0", true);
+    CHECK(strict.str() == file_contents);
+    CHECK(replaced.str() == file_contents);
+    CHECK(nlohmann::json::parse(strict.str())["machine_start_gcode"] == "G28\nG1 Z5");
+}
+
+TEST_CASE("save_to_json replaces invalid UTF-8 in a stream only when asked", "[Config]") {
+    DynamicPrintConfig config;
+    config.set_key_value("machine_start_gcode", new ConfigOptionString("G28 ; \xff"));
+
+    std::ostringstream strict, replaced;
+    CHECK_THROWS_AS(config.save_to_json(strict, "test_preset", "User", "1.0.0.0"), nlohmann::json::type_error);
+    REQUIRE_NOTHROW(config.save_to_json(replaced, "test_preset", "User", "1.0.0.0", true));
+    CHECK(nlohmann::json::parse(replaced.str())["machine_start_gcode"] == "G28 ; \xEF\xBF\xBD");
+}
+
+TEST_CASE("save_to_json leaves an existing file untouched when the config cannot be serialized", "[Config]") {
+    DynamicPrintConfig config;
+    config.set_key_value("machine_start_gcode", new ConfigOptionString("G28 ; \xff"));
+
+    ScopedTemporaryFile tmp(".json");
+    {
+        boost::nowide::ofstream ofs(tmp.string());
+        ofs << "previous";
+    }
+    CHECK_THROWS_AS(config.save_to_json(tmp.string(), "test_preset", "User", "1.0.0.0"), nlohmann::json::type_error);
+
+    boost::nowide::ifstream ifs(tmp.string());
+    const std::string contents((std::istreambuf_iterator<char>(ifs)), std::istreambuf_iterator<char>());
+    CHECK(contents == "previous");
+}
+
 TEST_CASE("plugin capability references survive string-map serialization", "[Config][plugins]") {
     const std::vector<std::string> refs = {
         "master_plugin;;header-stamp",
@@ -1091,3 +1146,128 @@ TEST_CASE("get_filament_type treats empty vector options as absent", "[Config][F
         REQUIRE(displayed == "Sup.PLA");
     }
 }
+
+namespace {
+
+// min_object_distance reads exactly these three options.
+DynamicPrintConfig spacing_config(PrinterTechnology tech, PrintSequence seq, double clearance_radius)
+{
+    DynamicPrintConfig c;
+    c.set_key_value("printer_technology", new ConfigOptionEnum<PrinterTechnology>(tech));
+    c.set_key_value("print_sequence", new ConfigOptionEnum<PrintSequence>(seq));
+    c.set_key_value("extruder_clearance_radius", new ConfigOptionFloat(clearance_radius));
+    return c;
+}
+
+} // namespace
+
+TEST_CASE("min_object_distance floors object spacing per print sequence", "[Config]")
+{
+    struct Case
+    {
+        std::string       description;
+        PrinterTechnology tech;
+        PrintSequence     sequence;
+        double            clearance_radius;
+        double            expected;
+    };
+
+    auto c = GENERATE(values<Case>({
+        {"sequential FFF takes a clearance radius above the floor", ptFFF, PrintSequence::ByObject, 12., 12.},
+        {"sequential FFF holds the floor at the radius",            ptFFF, PrintSequence::ByObject,  6.,  6.},
+        {"sequential FFF holds the floor below the radius",         ptFFF, PrintSequence::ByObject,  4.,  6.},
+        {"layered FFF ignores the clearance radius",                ptFFF, PrintSequence::ByLayer,  12.,  6.},
+        {"SLA is a flat 6mm",                                       ptSLA, PrintSequence::ByObject, 12.,  6.},
+        {"SLA ignores the print sequence too",                      ptSLA, PrintSequence::ByLayer,  12.,  6.},
+    }));
+
+    DYNAMIC_SECTION(c.description)
+    {
+        CHECK_THAT(min_object_distance(spacing_config(c.tech, c.sequence, c.clearance_radius)),
+                   Catch::Matchers::WithinAbs(c.expected, 1e-9));
+    }
+}
+
+TEST_CASE("min_object_distance yields no floor when an FFF config lacks the options", "[Config]")
+{
+    // Missing options yield 0 rather than an error, so a caller gets no floor at all.
+    SECTION("no clearance radius") {
+        DynamicPrintConfig c;
+        c.set_key_value("printer_technology", new ConfigOptionEnum<PrinterTechnology>(ptFFF));
+        c.set_key_value("print_sequence", new ConfigOptionEnum<PrintSequence>(PrintSequence::ByObject));
+        CHECK_THAT(min_object_distance(c), Catch::Matchers::WithinAbs(0., 1e-9));
+    }
+
+    SECTION("no print sequence") {
+        DynamicPrintConfig c;
+        c.set_key_value("printer_technology", new ConfigOptionEnum<PrinterTechnology>(ptFFF));
+        c.set_key_value("extruder_clearance_radius", new ConfigOptionFloat(12.));
+        CHECK_THAT(min_object_distance(c), Catch::Matchers::WithinAbs(0., 1e-9));
+    }
+
+    SECTION("nothing at all") {
+        CHECK_THAT(min_object_distance(DynamicPrintConfig{}), Catch::Matchers::WithinAbs(0., 1e-9));
+    }
+
+    SECTION("an unset printer technology is treated as FFF") {
+        DynamicPrintConfig c;
+        c.set_key_value("print_sequence", new ConfigOptionEnum<PrintSequence>(PrintSequence::ByObject));
+        c.set_key_value("extruder_clearance_radius", new ConfigOptionFloat(12.));
+        CHECK_THAT(min_object_distance(c), Catch::Matchers::WithinAbs(12., 1e-9));
+    }
+}
+
+TEST_CASE("Static print configs compare, order and hash by their option values", "[Config]")
+{
+    // PrintObjectConfig comes from PRINT_CONFIG_CLASS_DEFINE; PrintConfig combines MachineEnvelopeConfig
+    // and GCodeConfig through PRINT_CONFIG_CLASS_DERIVED_DEFINE. Both generate hash(), operator==,
+    // operator< and the option registration from the same option list. The hash inequalities use fixed
+    // inputs, so they are deterministic; they check that hash() covers the changed option.
+    SECTION("default-constructed configs are equal and find their options by key")
+    {
+        PrintObjectConfig a, b;
+        REQUIRE(a == b);
+        REQUIRE(a.hash() == b.hash());
+        REQUIRE_FALSE(a < b);
+        REQUIRE_FALSE(b < a);
+        REQUIRE(a.optptr("layer_height") == &a.layer_height);
+        REQUIRE(a.optptr("brim_object_gap") == &a.brim_object_gap);
+    }
+
+    SECTION("one differing option makes the configs unequal and orders them")
+    {
+        PrintObjectConfig a, b;
+        b.layer_height.value = a.layer_height.value + 0.05;
+        REQUIRE(a != b);
+        REQUIRE(a.hash() != b.hash());
+        REQUIRE(a < b);
+        REQUIRE_FALSE(b < a);
+    }
+
+    SECTION("ordering is decided by the first option in declaration order that differs")
+    {
+        PrintObjectConfig a, b;
+        a.brim_object_gap.value = b.brim_object_gap.value + 1.0;  // declared first
+        a.layer_height.value    = b.layer_height.value - 0.05;    // declared later, points the other way
+        REQUIRE(b < a);
+        REQUIRE_FALSE(a < b);
+    }
+
+    SECTION("a derived config sees differences in its parents and in its own options")
+    {
+        PrintConfig a, b;
+        REQUIRE(a == b);
+        REQUIRE(a.hash() == b.hash());
+
+        b.gcode_flavor.value = b.gcode_flavor.value == gcfMarlinLegacy ? gcfKlipper : gcfMarlinLegacy;  // GCodeConfig parent
+        REQUIRE(a != b);
+        REQUIRE(a.hash() != b.hash());
+
+        PrintConfig c, d;
+        d.skirt_distance.value = c.skirt_distance.value + 1.0;  // PrintConfig's own list
+        REQUIRE(c != d);
+        REQUIRE(c.hash() != d.hash());
+        REQUIRE(c.optptr("skirt_distance") == &c.skirt_distance);
+        REQUIRE(c.optptr("gcode_flavor") == &c.gcode_flavor);
+    }
+}

tests/libslic3r/test_config_variant_expansion.cpp

@@ -484,6 +484,34 @@ TEST_CASE("update_values_to_printer_extruders_for_multiple_filaments resolves pe
         REQUIRE(config.option<ConfigOptionFloats>("filament_max_volumetric_speed")->values == std::vector<double>({12., 21.}));
         REQUIRE(config.option<ConfigOptionInts>("filament_self_index")->values == std::vector<int>({1, 2}));
     }
+
+    SECTION("a variant option shorter than the filament slots keeps its first value instead of zero") {
+        DynamicPrintConfig config;
+        config.option<ConfigOptionEnumsGeneric>("extruder_type", true)->values = {etDirectDrive, etDirectDrive};
+        config.option<ConfigOptionEnumsGeneric>("nozzle_volume_type", true)->values = {nvtStandard, nvtHighFlow};
+        config.option<ConfigOptionStrings>("extruder_variant_list", true)->values = {"Direct Drive Standard,Direct Drive High Flow",
+                                                                                     "Direct Drive Standard,Direct Drive High Flow"};
+        make_filament_arrays(config);
+        config.option<ConfigOptionInts>("filament_map", true)->values = {1, 2};
+        // no loaded preset carries the key, so only its single registered default is present
+        config.option<ConfigOptionFloatsNullable>("filament_cooling_before_tower", true)->values = {10.};
+        // only the first filament's two variant columns were loaded
+        config.option<ConfigOptionFloatsNullable>("filament_ramming_volumetric_speed", true)->values = {-1., -2.};
+
+        std::vector<std::vector<NozzleVolumeType>> nozzle_volume_types;
+        int extruder_count = 2;
+        int count = config.get_extruder_nozzle_volume_count(extruder_count, nozzle_volume_types);
+
+        config.update_values_to_printer_extruders_for_multiple_filaments(config, extruder_count, count, filament_keys,
+            "filament_self_index", "filament_extruder_variant");
+
+        // filament 2 resolves to column 3 (its extruder's High Flow column), past the end of both vectors
+        REQUIRE_THAT(config.option<ConfigOptionFloatsNullable>("filament_cooling_before_tower")->values,
+                     Catch::Matchers::Approx(std::vector<double>({10., 10.})));
+        REQUIRE_THAT(config.option<ConfigOptionFloatsNullable>("filament_ramming_volumetric_speed")->values,
+                     Catch::Matchers::Approx(std::vector<double>({-1., -1.})));
+        REQUIRE(config.option<ConfigOptionFloats>("filament_max_volumetric_speed")->values == std::vector<double>({12., 21.}));
+    }
 }
 
 // update_values_from_multi_to_multi_2 walks the DESTINATION PRINTER's variant list while writing

tests/libslic3r/test_lay_on_face.cpp

@@ -0,0 +1,205 @@
+#include <catch2/catch_all.hpp>
+
+#include "libslic3r/LayOnFace.hpp"
+#include "libslic3r/Model.hpp"
+
+using namespace Slic3r;
+using Catch::Matchers::WithinAbs;
+
+namespace {
+
+// Adds a box part spanning `origin` to `origin + size`, in object coordinates.
+void add_box(ModelObject &object, const Vec3d &size, const Vec3d &origin = Vec3d::Zero())
+{
+    TriangleMesh mesh = make_cube(size.x(), size.y(), size.z());
+    mesh.translate(origin.cast<float>());
+    object.add_volume(std::move(mesh), ModelVolumeType::MODEL_PART, false);
+}
+
+ModelObject &add_box_object(Model &model, const Vec3d &size)
+{
+    ModelObject *object = model.add_object();
+    add_box(*object, size);
+    object->add_instance();
+    return *object;
+}
+
+// A 30 x 30 x 2 plate with three 1 mm thick, 20 mm tall ribs along Y. The rib sides facing -X add up
+// to more area than the plate's bottom, but only the bottom is a face of the convex hull.
+ModelObject &add_ribbed_plate(Model &model)
+{
+    ModelObject *object = model.add_object();
+    add_box(*object, { 30, 30, 2 });
+    for (double x : { 5., 14.5, 24. })
+        add_box(*object, { 1, 30, 20 }, { x, 0, 2 });
+    object->add_instance();
+    return *object;
+}
+
+std::vector<LayOnFacePlane> instance_planes(const ModelObject &object)
+{
+    return lay_on_face_planes(object, object.instances.front()->get_matrix_no_offset());
+}
+
+void lay_on_largest_face(ModelObject &object)
+{
+    const std::vector<LayOnFacePlane> planes = instance_planes(object);
+    const int                         idx    = find_largest_plane(planes);
+    REQUIRE(idx >= 0);
+    lay_on_face(object, 0, planes[idx].normal);
+}
+
+void check_size(const ModelObject &object, const Vec3d &expected)
+{
+    const Vec3d size = object.instance_bounding_box(0).size();
+    CHECK_THAT(size.x(), WithinAbs(expected.x(), 1e-3));
+    CHECK_THAT(size.y(), WithinAbs(expected.y(), 1e-3));
+    CHECK_THAT(size.z(), WithinAbs(expected.z(), 1e-3));
+}
+
+void check_on_bed(const ModelObject &object) { CHECK_THAT(object.instance_bounding_box(0).min.z(), WithinAbs(0., 1e-3)); }
+
+} // namespace
+
+TEST_CASE("A tilted box is laid on its largest face and dropped onto the bed", "[LayOnFace]")
+{
+    Model        model;
+    ModelObject &box = add_box_object(model, { 40, 20, 10 }); // the 40 x 20 faces are the largest
+    box.instances.front()->set_rotation({ 0.3, 0.5, 0.2 });
+    box.instances.front()->set_offset({ 0, 0, 50 });
+    REQUIRE(box.instance_bounding_box(0).size().z() > 11.);
+
+    const std::vector<LayOnFacePlane> planes = instance_planes(box);
+    REQUIRE(planes.size() == 6);
+    CHECK_THAT(planes.front().area, WithinAbs(40. * 20., 1e-2));
+
+    lay_on_largest_face(box);
+    CHECK_THAT(box.instance_bounding_box(0).size().z(), WithinAbs(10., 1e-3));
+    check_on_bed(box);
+}
+
+TEST_CASE("A box lying on one of its equally large faces is not flipped", "[LayOnFace]")
+{
+    // A half turn about X puts the other large face down, so the two cases expect different faces
+    // and neither can pass on the order in which the hull lists them.
+    const double rotation_x = GENERATE(0., PI);
+    Model        model;
+    ModelObject &box = add_box_object(model, { 40, 20, 10 }); // the bottom and top are both 40 x 20
+    box.instances.front()->set_rotation({ rotation_x, 0, 0 });
+    const Transform3d before = box.instances.front()->get_matrix_no_offset();
+
+    const std::vector<LayOnFacePlane> planes = instance_planes(box);
+    const int                         idx    = find_largest_plane(planes);
+    REQUIRE(idx >= 0);
+    // The face down on the plate is the object's -Z face, or its +Z face after the half turn.
+    CHECK_THAT(planes[idx].normal.z(), WithinAbs(rotation_x == 0. ? -1. : 1., 1e-6));
+
+    lay_on_face(box, 0, planes[idx].normal);
+    CHECK(box.instances.front()->get_matrix_no_offset().isApprox(before, 1e-9));
+}
+
+TEST_CASE("Faces are chosen from the orientation left by an earlier part rotation", "[LayOnFace]")
+{
+    Model        model;
+    ModelObject &box = add_box_object(model, { 40, 20, 10 });
+    box.rotate(PI / 2., X); // what --rotate-x 90 does: rotates the parts, not the instance
+    check_size(box, { 40, 10, 20 });
+
+    SECTION("the largest face") {
+        lay_on_largest_face(box);
+        check_size(box, { 40, 20, 10 });
+        check_on_bed(box);
+    }
+
+    SECTION("the face pointing along +X") {
+        const std::vector<LayOnFacePlane> planes = instance_planes(box);
+        const int                         idx    = find_plane_by_normal(planes, { 1, 0, 0 });
+        REQUIRE(idx >= 0);
+        CHECK_THAT(planes[idx].normal.x(), WithinAbs(1., 1e-6));
+        lay_on_face(box, 0, planes[idx].normal);
+        check_size(box, { 20, 10, 40 });
+        check_on_bed(box);
+    }
+}
+
+TEST_CASE("Objects are laid on their own faces independently", "[LayOnFace]")
+{
+    Model model;
+    // Standing on end through its instance rotation.
+    ModelObject &standing = add_box_object(model, { 40, 20, 10 });
+    standing.instances.front()->set_rotation({ 0, PI / 2., 0 });
+    // Standing on edge through a part rotation, lifted above the bed.
+    ModelObject &on_edge = add_box_object(model, { 30, 20, 5 });
+    on_edge.rotate(PI / 2., X);
+    on_edge.instances.front()->set_offset({ 100, 0, 30 });
+    check_size(standing, { 10, 20, 40 });
+    check_size(on_edge, { 30, 5, 20 });
+
+    for (ModelObject *object : model.objects)
+        lay_on_largest_face(*object);
+
+    check_size(standing, { 40, 20, 10 });
+    check_on_bed(standing);
+    check_size(on_edge, { 30, 20, 5 });
+    check_on_bed(on_edge);
+}
+
+TEST_CASE("A part rests on its largest hull face even when parallel inner faces add up to more area", "[LayOnFace]")
+{
+    Model        model;
+    ModelObject &plate = add_ribbed_plate(model);
+
+    double area_facing_minus_x = 0.;
+    for (const ModelVolume *volume : plate.volumes) {
+        const indexed_triangle_set &its = volume->mesh().its;
+        for (const Vec3i32 &face : its.indices) {
+            const Vec3d cross = (its.vertices[face[1]] - its.vertices[face[0]]).cast<double>().cross(
+                (its.vertices[face[2]] - its.vertices[face[0]]).cast<double>());
+            if (cross.normalized().x() < -0.999)
+                area_facing_minus_x += 0.5 * cross.norm();
+        }
+    }
+    // Summing triangle area per normal would pick a rib side over the 900 mm² bottom.
+    REQUIRE(area_facing_minus_x > 30. * 30.);
+
+    plate.instances.front()->set_rotation({ 0, PI / 2., 0 }); // stand the plate on its side
+    check_size(plate, { 22, 30, 30 });
+
+    const std::vector<LayOnFacePlane> planes = instance_planes(plate);
+    const int                         idx    = find_largest_plane(planes);
+    REQUIRE(idx >= 0);
+    CHECK_THAT(planes[idx].area, WithinAbs(30. * 30., 1e-2));
+    CHECK_THAT(planes[idx].normal.z(), WithinAbs(-1., 1e-6));
+
+    lay_on_face(plate, 0, planes[idx].normal);
+    check_size(plate, { 30, 30, 22 });
+    check_on_bed(plate);
+}
+
+TEST_CASE("Faces are selected in object coordinates whatever the instance rotation", "[LayOnFace]")
+{
+    Model        model;
+    ModelObject &plate = add_ribbed_plate(model);
+    plate.instances.front()->set_rotation({ 0, 0, PI / 2. });
+    const Transform3d                 instance_matrix = plate.instances.front()->get_matrix_no_offset();
+    const std::vector<LayOnFacePlane> planes          = lay_on_face_planes(plate, instance_matrix);
+    REQUIRE_FALSE(planes.empty());
+
+    // Every face center, as --inspect-mesh reports it, selects its own face.
+    for (size_t i = 0; i < planes.size(); ++i)
+        CHECK(find_plane_at_point(planes, instance_matrix, planes[i].center, 0.01) == int(i));
+
+    const int bottom = find_plane_at_point(planes, instance_matrix, { 15, 15, 0 }, 0.01);
+    REQUIRE(bottom >= 0);
+    CHECK_THAT(planes[bottom].normal.z(), WithinAbs(-1., 1e-6));
+    CHECK(find_plane_by_normal(planes, { 0, 0, -1 }) == bottom);
+    // Above the bottom plane, and on a rib side that lies inside the hull.
+    CHECK(find_plane_at_point(planes, instance_matrix, { 15, 15, 0.5 }, 0.01) == -1);
+    CHECK(find_plane_at_point(planes, instance_matrix, { 14.5, 15, 12 }, 0.01) == -1);
+}
+
+TEST_CASE("A part too small to rest on offers no faces", "[LayOnFace]")
+{
+    Model model;
+    CHECK(instance_planes(add_box_object(model, { 2, 2, 2 })).empty()); // every face is 4 mm², under the 5 mm² minimum
+}

tests/libslic3r/test_marchingsquares.cpp

@@ -1,4 +1,6 @@
+#ifndef NOMINMAX
 #define NOMINMAX
+#endif
 
 #include <catch2/catch_all.hpp>
 #include "test_utils.hpp"

tests/libslic3r/test_minimum_spanning_tree.cpp

@@ -0,0 +1,66 @@
+#include <catch2/catch_all.hpp>
+
+#include <algorithm>
+
+#include "libslic3r/MinimumSpanningTree.hpp"
+#include "libslic3r/Point.hpp"
+
+using namespace Slic3r;
+
+// A 5x5 lattice: at every step of Prim's algorithm several candidates sit at the same
+// distance from the tree, so the tie-break decides the tree's shape.
+static std::vector<Point> lattice()
+{
+    std::vector<Point> vertices;
+    for (int y = 0; y < 5; ++y)
+        for (int x = 0; x < 5; ++x)
+            vertices.emplace_back(Point::new_scale(x, y));
+    return vertices;
+}
+
+static std::vector<Point> sorted_neighbours(const MinimumSpanningTree &mst, const Point &vertex)
+{
+    std::vector<Point> neighbours = mst.adjacent_nodes(vertex);
+    std::sort(neighbours.begin(), neighbours.end());
+    return neighbours;
+}
+
+TEST_CASE("Minimum spanning tree connects every vertex", "[MinimumSpanningTree]")
+{
+    const std::vector<Point> vertices = lattice();
+    const MinimumSpanningTree mst(vertices);
+
+    REQUIRE(mst.vertices().size() == vertices.size());
+    size_t adjacency_entries = 0;
+    for (const Point &vertex : vertices) {
+        const std::vector<Point> neighbours = mst.adjacent_nodes(vertex);
+        REQUIRE(! neighbours.empty());
+        adjacency_entries += neighbours.size();
+    }
+    // A tree on n vertices has n - 1 edges, each listed from both ends.
+    REQUIRE(adjacency_entries == 2 * (vertices.size() - 1));
+}
+
+TEST_CASE("Minimum spanning tree does not depend on the order of the non-root vertices", "[MinimumSpanningTree][Regression]")
+{
+    const std::vector<Point> vertices = lattice();
+    const MinimumSpanningTree reference(vertices);
+
+    // The root stays first: Prim's tree legitimately depends on where it starts.
+    // Every other order of the remaining vertices must give the same tree.
+    std::vector<std::vector<Point>> orders;
+    orders.emplace_back(vertices);
+    std::reverse(orders.back().begin() + 1, orders.back().end());
+    for (size_t shift = 1; shift + 1 < vertices.size(); ++shift) {
+        orders.emplace_back(vertices);
+        std::rotate(orders.back().begin() + 1, orders.back().begin() + 1 + shift, orders.back().end());
+    }
+
+    for (const std::vector<Point> &order : orders) {
+        const MinimumSpanningTree mst(order);
+        for (const Point &vertex : vertices) {
+            INFO("vertex " << vertex.x() << "," << vertex.y());
+            REQUIRE(sorted_neighbours(mst, vertex) == sorted_neighbours(reference, vertex));
+        }
+    }
+}

tests/libslic3r/test_preset_diff.cpp

@@ -33,3 +33,20 @@ TEST_CASE("deep_diff flags new vector entries that duplicate values[0]", "[Prese
     // specific to new indices rather than flagging the whole vector.
     REQUIRE(std::find(diff.begin(), diff.end(), "nozzle_diameter#0") == diff.end());
 }
+
+TEST_CASE("deep_diff distinguishes absolute and percentage speeds for each variant", "[PresetDiff][Config]")
+{
+    const size_t changed_index = GENERATE(size_t(0), size_t(1));
+    Preset reference(Preset::TYPE_PRINT, "ref");
+    reference.config.set_key_value("small_perimeter_speed", new ConfigOptionFloatsOrPercents{{50., false}, {50., false}});
+
+    Preset edited = reference;
+    edited.config.option<ConfigOptionFloatsOrPercents>("small_perimeter_speed")->values[changed_index].percent = true;
+
+    const auto diff = PresetCollection::dirty_options(&edited, &reference, /*deep_compare=*/true);
+    REQUIRE(diff == std::vector<std::string>{"small_perimeter_speed#" + std::to_string(changed_index)});
+
+    DynamicPrintConfig transferred = reference.config;
+    transferred.apply_only(edited.config, diff);
+    REQUIRE(*transferred.option("small_perimeter_speed") == *edited.config.option("small_perimeter_speed"));
+}

tests/libslic3r/test_preset_options.cpp

@@ -0,0 +1,70 @@
+// Regression test for the "option in def + UI but missing from preset key list"
+// crash class.
+//
+// The print preset's DynamicPrintConfig is seeded with only the keys returned by
+// Preset::print_options() (PresetBundle.cpp). A field added to PrintRegionConfig
+// or PrintObjectConfig and registered via print_config_def plus a TabPrint
+// optgroup, but left out of print_options(), still gets its control built; on tab
+// activation reload_config -> get_config_value dispatches to opt_bool/opt_int on a
+// DynamicPrintConfig with no entry for the key, and the accessor null-derefs the
+// result of option<T>(key).
+//
+// The invariant asserted here is the inverse: every key declared on
+// PrintRegionConfig and PrintObjectConfig appears in Preset::print_options() or
+// Preset::filament_options(), the two preset key lists that seed a print preset's
+// DynamicConfig.
+
+#include <catch2/catch_all.hpp>
+
+#include "libslic3r/Preset.hpp"
+#include "libslic3r/PrintConfig.hpp"
+
+#include <set>
+
+using namespace Slic3r;
+
+namespace {
+
+// Deprecated keys renamed in handle_legacy() (ironing_direction ->
+// ironing_angle, wall_infill_order -> wall_sequence); neither is in a
+// preset list. Register new options in a preset list, not here.
+const std::set<std::string> kDeprecatedRegionFields = {
+    "ironing_direction",
+    "wall_infill_order",
+};
+
+void check_keys_are_in_a_preset(const t_config_option_keys& keys, const std::string& class_name)
+{
+    REQUIRE_FALSE(keys.empty());
+    const auto& print_options    = Preset::print_options();
+    const auto& filament_options = Preset::filament_options();
+    const std::set<std::string> in_print(print_options.begin(), print_options.end());
+    const std::set<std::string> in_filament(filament_options.begin(), filament_options.end());
+    for (const std::string& key : keys) {
+        DYNAMIC_SECTION(class_name << "::" << key)
+        {
+            INFO("'" << key << "' on " << class_name
+                     << " is missing from "
+                        "Preset::print_options()/filament_options(); add it to "
+                        "s_Preset_print_options (or s_Preset_filament_options) in Preset.cpp.");
+            const bool registered = in_print.count(key) || in_filament.count(key) || kDeprecatedRegionFields.count(key);
+            REQUIRE(registered);
+        }
+    }
+}
+
+} // namespace
+
+// Bodies are laid out like the rest of the test suite rather than collapsed
+// onto the brace line.
+// clang-format off
+TEST_CASE("Every PrintRegionConfig field is registered in a preset key list", "[Preset][Config]")
+{
+    check_keys_are_in_a_preset(PrintRegionConfig::defaults().keys(), "PrintRegionConfig");
+}
+
+TEST_CASE("Every PrintObjectConfig field is registered in a preset key list", "[Preset][Config]")
+{
+    check_keys_are_in_a_preset(PrintObjectConfig::defaults().keys(), "PrintObjectConfig");
+}
+// clang-format on

tests/libslic3r/test_preset_setting_id.cpp

@@ -5,10 +5,10 @@
 using namespace Slic3r;
 
 // Golden vectors from the Python reference generate_preset_setting_id (defined in
-// scripts/orca_id_tool.py). The C++ generate_preset_setting_id() MUST stay byte-identical
+// scripts/orca_profile_tool.py). The C++ generate_preset_setting_id() MUST stay byte-identical
 // to it, otherwise app-side on-the-fly ids would diverge from the
 // script-assigned ones in the profiles. Regenerate a vector with:
-//   python3 -c "import sys; sys.path.insert(0, 'scripts'); from orca_id_tool import generate_preset_setting_id as g; print(g('Afinia','filament','Afinia ABS @Afinia H400'))"
+//   python3 -c "import sys; sys.path.insert(0, 'scripts'); from orca_profile_tool import generate_preset_setting_id as g; print(g('Afinia','filament','Afinia ABS @Afinia H400'))"
 TEST_CASE("preset setting_id matches the Python reference", "[Preset][setting_id]") {
     struct Vec { const char* vendor; const char* type; const char* name; const char* expected; };
     const Vec vectors[] = {

tests/libslic3r/test_toolordering_nozzle_group.cpp

@@ -163,6 +163,50 @@ TEST_CASE("H2C multi-nozzle: filaments get distinct nozzles on the 6-nozzle extr
     }
 }
 
+TEST_CASE("Grouping context spans the filament count with mis-sized config arrays", "[ToolOrdering][H2C]")
+{
+    // FilamentGroup indexes the grouping context's filament_info by filament id, so a short
+    // per-filament array must not shorten it: the reads run off the end.
+    DynamicPrintConfig config = DynamicPrintConfig::full_print_config();
+    // Single 6-nozzle extruder: opens the grouping engine without needing a BBL multi-extruder.
+    config.option<ConfigOptionFloats>("nozzle_diameter", true)->values = {0.4};
+    config.option<ConfigOptionIntsNullable>("extruder_max_nozzle_count", true)->values = {6};
+    config.option<ConfigOptionStrings>("extruder_nozzle_stats", true)->values = {"Standard#6"};
+
+    // Four filaments, with filament_type / filament_is_support left short on purpose.
+    config.option<ConfigOptionStrings>("filament_colour", true)->values = {"#FF0000", "#00FF00", "#0000FF", "#FFFF00"};
+    config.option<ConfigOptionStrings>("filament_type", true)->values = {"PLA"};
+    config.option<ConfigOptionBools>("filament_is_support", true)->values = {0};
+    config.option<ConfigOptionFloats>("filament_diameter", true)->values = {1.75, 1.75, 1.75, 1.75};
+    config.option<ConfigOptionInts>("filament_map", true)->values = {1, 1, 1, 1};
+    config.option<ConfigOptionFloats>("flush_volumes_matrix", true)->values = std::vector<double>(16, 140.);
+    config.option<ConfigOptionFloats>("flush_multiplier", true)->values = {1.};
+
+    Model model;
+    model.add_object("cube", "", make_cube(20, 20, 20))->add_instance();
+
+    Print print;
+    print.apply(model, config);
+    // apply() does not pad the per-filament arrays, so the mis-sizing survives into the engine.
+    REQUIRE(print.config().filament_type.values.size() < print.config().filament_colour.values.size());
+
+    std::vector<std::vector<unsigned int>> layer_filaments = {{0, 1}, {1, 2}, {2, 3}};
+
+    SECTION("short per-filament arrays still yield one entry per filament") {
+        auto result = ToolOrdering::get_recommended_filament_maps(layer_filaments, &print, FilamentMapMode::fmmAutoForFlush, {}, {});
+        REQUIRE(result.get_extruder_map(false).size() == 4);
+        for (int f = 0; f < 4; ++f)
+            REQUIRE(result.get_extruder_id(f) == 0);
+    }
+
+    SECTION("filament_ids longer than the filament count is truncated, not paired past the end") {
+        config.option<ConfigOptionStrings>("filament_ids", true)->values = {"a", "b", "c", "d", "e", "f"};
+        print.apply(model, config);
+        auto result = ToolOrdering::get_recommended_filament_maps(layer_filaments, &print, FilamentMapMode::fmmAutoForFlush, {}, {});
+        REQUIRE(result.get_extruder_map(false).size() == 4);
+    }
+}
+
 TEST_CASE("H2C dynamic selector: per-layer nozzle ids reach the g-code surface", "[ToolOrdering][H2C][Dynamic]")
 {
     // The per-layer regroup engine
@@ -981,3 +1025,41 @@ TEST_CASE("Selector slicing keeps the result valid across re-apply", "[Print][H2
     REQUIRE(status != PrintBase::APPLY_STATUS_INVALIDATED);
     REQUIRE(print.is_step_done(psSlicingFinished));
 }
+
+TEST_CASE("parse_cyclic_order parses user cyclic toolchange sequences", "[ToolOrdering][Cyclic]")
+{
+    // Filament numbers are 1-based in the UI; the parser returns 0-based indices.
+    SECTION("well-formed sequence") {
+        REQUIRE(parse_cyclic_order("3,2,1,4", 4) == std::vector<unsigned int>({2, 1, 0, 3}));
+    }
+
+    SECTION("surrounding whitespace is tolerated") {
+        REQUIRE(parse_cyclic_order(" 3 , 2 ,1, 4 ", 4) == std::vector<unsigned int>({2, 1, 0, 3}));
+    }
+
+    SECTION("out-of-range and non-positive entries are dropped") {
+        // 0 is below the 1-based range, 5 is above it for a 4-filament setup, -1 is invalid.
+        REQUIRE(parse_cyclic_order("0,5,-1,2", 4) == std::vector<unsigned int>({1}));
+    }
+
+    SECTION("duplicates keep only the first occurrence") {
+        REQUIRE(parse_cyclic_order("2,2,1,2", 4) == std::vector<unsigned int>({1, 0}));
+    }
+
+    SECTION("garbage tokens are ignored") {
+        REQUIRE(parse_cyclic_order("3,abc,,2,x1", 4) == std::vector<unsigned int>({2, 1}));
+    }
+
+    SECTION("tokens that only start with a number are ignored") {
+        // "2x" must be dropped rather than parsed as filament 2.
+        REQUIRE(parse_cyclic_order("3,2x,1", 4) == std::vector<unsigned int>({2, 0}));
+    }
+
+    SECTION("empty string yields an empty order") {
+        REQUIRE(parse_cyclic_order("", 4).empty());
+    }
+
+    SECTION("a partial sequence only names the filaments it lists") {
+        REQUIRE(parse_cyclic_order("3,1", 4) == std::vector<unsigned int>({2, 0}));
+    }
+}

tests/libslic3r/test_utils.cpp

@@ -2,6 +2,15 @@
 
 #include "libslic3r/Utils.hpp"
 
+#include "test_utils.hpp"
+
+#include <boost/filesystem.hpp>
+
+#include <algorithm>
+#include <cctype>
+#include <fstream>
+#include <string>
+
 #ifndef _WIN32
 #include <unistd.h>     // getuid
 #endif
@@ -52,3 +61,94 @@ TEST_CASE("per-user temp root is unchanged on Windows, isolated elsewhere", "[ut
     REQUIRE_THAT(root, Catch::Matchers::StartsWith(base + "/orcaslicer_"));
 #endif
 }
+
+TEST_CASE("copy_file reports the OS error when the destination cannot be written", "[utils]") {
+    ScopedTemporaryFile source(".txt");
+    {
+        std::ofstream ofs(source.string(), std::ios::binary);
+        ofs << "orca";
+    }
+    REQUIRE(boost::filesystem::exists(source.path()));
+
+    // A directory that was never created, so the copy fails on every platform.
+    const boost::filesystem::path destination = source.path().parent_path() / "orca-missing-dir" / "copy.txt";
+    REQUIRE_FALSE(boost::filesystem::exists(destination.parent_path()));
+
+    std::string error_message;
+    REQUIRE(copy_file(source.string(), destination.string(), error_message) == FAIL_COPY_FILE);
+    REQUIRE_FALSE(error_message.empty());
+
+#ifdef _WIN32
+    // The Windows branch formats GetLastError() itself. Writing that as
+    // "Error: " + errCode adds an integer to a string literal, which indexes into the
+    // literal instead of appending and runs off its end for any code above 7.
+    const std::string prefix = "Error: ";
+    REQUIRE(error_message.rfind(prefix, 0) == 0);
+
+    const std::string code = error_message.substr(prefix.size());
+    REQUIRE_FALSE(code.empty());
+    REQUIRE(std::all_of(code.begin(), code.end(), [](unsigned char c) { return std::isdigit(c) != 0; }));
+#endif // _WIN32
+}
+
+TEST_CASE("A resolved input path still names the same file after the working directory changes", "[utils]") {
+    ScopedTemporaryFile model(".3mf");
+    { std::ofstream out(model.string()); out << "3mf"; }
+    const std::string name = model.path().filename().string();
+
+    // Resolve the bare name from the directory holding the file, then move away from it. The guard
+    // restores the directory the test started in, wherever this leaves it.
+    ScopedWorkingDirectory cwd(model.path().parent_path());
+    const std::string resolved = resolve_cli_input_path(name);
+    boost::filesystem::current_path(boost::filesystem::path(TEST_DATA_DIR));
+
+    REQUIRE(boost::filesystem::exists(resolved));
+    REQUIRE(boost::filesystem::equivalent(resolved, model.path()));
+    // Control: the bare name finds nothing from here, so resolving it this late would have failed.
+    REQUIRE_FALSE(boost::filesystem::exists(name));
+}
+
+TEST_CASE("resolve_cli_input_path completes a relative path against the working directory", "[utils]") {
+    ScopedWorkingDirectory cwd(boost::filesystem::temp_directory_path());
+    // Read back rather than reusing temp_directory_path(): changing to it resolves any symlink.
+    const boost::filesystem::path here = boost::filesystem::current_path();
+
+    SECTION("a bare name") {
+        REQUIRE(resolve_cli_input_path("model.3mf") == (here / "model.3mf").make_preferred().string());
+    }
+    SECTION("a ./ prefix is dropped") {
+        REQUIRE(resolve_cli_input_path("./model.3mf") == (here / "model.3mf").make_preferred().string());
+    }
+    SECTION("a ../ traversal is collapsed") {
+        REQUIRE(resolve_cli_input_path("../model.3mf") == (here.parent_path() / "model.3mf").make_preferred().string());
+    }
+}
+
+TEST_CASE("resolve_cli_input_path leaves inputs that must not be completed unchanged", "[utils]") {
+    SECTION("an absolute path") {
+        const boost::filesystem::path absolute = (boost::filesystem::temp_directory_path() / "model.3mf").make_preferred();
+        REQUIRE(resolve_cli_input_path(absolute.string()) == absolute.string());
+    }
+#ifdef _WIN32
+    // Every absolute form Windows accepts opens today, so each must come back byte for byte:
+    // normalizing them would rewrite the forward slashes and rebuild the \\?\ and UNC prefixes.
+    SECTION("an absolute Windows path of any form") {
+        for (const std::string absolute : {R"(C:\models\model.3mf)",
+                                           R"(C:/models/model.3mf)",
+                                           R"(\\server\share\model.3mf)",
+                                           R"(\\?\C:\models\model.3mf)"})
+            REQUIRE(resolve_cli_input_path(absolute) == absolute);
+    }
+#endif
+    // These are downloaded rather than opened, and completing one would produce a path, not a URL.
+    SECTION("a custom open protocol URL") {
+        for (const std::string url : {"orcaslicer://open/?file=https://example.com/model.3mf",
+                                      "prusaslicer://open/?file=https://example.com/model.3mf",
+                                      "bambustudio://open/?file=https://example.com/model.3mf",
+                                      "cura://open/?file=https://example.com/model.3mf"})
+            REQUIRE(resolve_cli_input_path(url) == url);
+    }
+    SECTION("an empty argument") {
+        REQUIRE(resolve_cli_input_path("").empty());
+    }
+}

tests/libslic3r/test_wipe_tower.cpp

@@ -0,0 +1,289 @@
+#include <catch2/catch_all.hpp>
+
+#include <cmath>
+
+#include "libslic3r/BoundingBox.hpp"
+#include "libslic3r/ClipperUtils.hpp"
+#include "libslic3r/GCode/WipeTower.hpp"
+#include "libslic3r/GCode/WipeTower2.hpp"
+#include "libslic3r/Print.hpp"
+#include "libslic3r/PrintConfig.hpp"
+
+using namespace Slic3r;
+using Catch::Matchers::WithinAbs;
+
+// A Bambu P1S project that reproduced the off-plate brim: two PLAs priming 30 and 45 mm3 in
+// separate adhesiveness categories on a 35 mm tower, 0.21 mm layers, 0.4 nozzle (0.5 mm lines),
+// 150 % infill gap (0.75 mm line pitch), rib width 8, 16 mm tall.
+static std::vector<WipeTower::PurgeEstimate> cube_purges(int first_category = 100)
+{
+    return {{30.f, first_category}, {45.f, 0}};
+}
+
+TEST_CASE("Cone base polygon bulges past the body box", "[WipeTower]") {
+    // Zero angle: plain body box.
+    const Polygon box = WipeTower2::cone_base_polygon(35., 20., 100., 0.);
+    CHECK(box.points.size() == 4);
+    CHECK(get_extents(box).size() == Point::new_scale(Vec2d(35., 20.)));
+    // A 25-degree cone on a 100 mm tower: base radius R = tan(12.5deg)*100 = 22.2 mm,
+    // which exceeds the body half-depth, so the footprint bulges to center +- R in y
+    // (support_scale keeps the x extent compressed near the body).
+    const Polygon     base = WipeTower2::cone_base_polygon(35., 20., 100., 25.);
+    const BoundingBox bb   = get_extents(base);
+    const double      R    = std::tan(25. / 2. * M_PI / 180.) * 100.;
+    CHECK_THAT(unscaled(bb.min.y()), WithinAbs(10. - R, 0.1));
+    CHECK_THAT(unscaled(bb.max.y()), WithinAbs(10. + R, 0.1));
+    // The footprint always contains the body box.
+    CHECK(diff(Polygons{box}, Polygons{base}).empty());
+}
+
+TEST_CASE("Type1 block-stack depth quantizes each purge to whole lines", "[WipeTower]") {
+    // A 0.5 mm line at 0.21 mm carries 0.0955 mm3 per mm, so across the 34 mm between the
+    // perimeters 30 mm3 is 10 lines and 45 mm3 is 14: 7.5 + 10.5 at the 0.75 mm pitch behind
+    // one perimeter width. The generated mesh of the project measured exactly this.
+    CHECK_THAT(WipeTower::estimate_tower_blocks_depth(cube_purges(), 35.f, 0.21f, 0.4f, 1.5f), WithinAbs(18.5f, 0.01f));
+    // Sharing one category, a layer can never purge into every filament (one of them starts
+    // the layer), so the block is sized by its worst layer and the 10-line purge drops out.
+    CHECK_THAT(WipeTower::estimate_tower_blocks_depth(cube_purges(0), 35.f, 0.21f, 0.4f, 1.5f), WithinAbs(11.0f, 0.01f));
+    CHECK_THAT(WipeTower::estimate_tower_blocks_depth({}, 35.f, 0.2f, 0.4f, 1.f), WithinAbs(0.f, 1e-6f));
+    // A width narrower than two perimeter widths cannot hold purge lines.
+    CHECK_THAT(WipeTower::estimate_tower_blocks_depth({{45.f, 0}}, 0.9f, 0.2f, 0.4f, 1.f), WithinAbs(0.f, 1e-6f));
+}
+
+TEST_CASE("A nozzle change adds its ramming lines to the block", "[WipeTower]") {
+    // 10 mm of 1.75 mm filament (24.05 mm3) laid as 1.0 mm nozzle-change lines at 0.2 mm
+    // (0.1914 mm2 each) is 125.7 mm; across the 48.5 mm available that is 3 lines of 1.0 mm.
+    std::vector<WipeTower::PurgeEstimate> purges{{100.f, 0}, {100.f, 0}};
+    const float without_change = WipeTower::estimate_tower_blocks_depth(purges, 50.f, 0.2f, 0.4f, 1.f);
+    purges.front().filament_change_length = 10.f;
+    CHECK_THAT(WipeTower::estimate_tower_blocks_depth(purges, 50.f, 0.2f, 0.4f, 1.f) - without_change, WithinAbs(3.f, 1e-4f));
+}
+
+TEST_CASE("Rib tower footprint estimate covers the generated footprint", "[WipeTower]") {
+    // The generated first-layer wall bbox of the project measured 29.56 mm from the sliced
+    // G-code; the volume-only estimate said 23.585 mm.
+    const float side = WipeTower::estimate_rib_tower_bbox_side(cube_purges(), 35.f, 0.21f, 0.4f, 1.5f, 8.f, 0.f, 16.f);
+    CHECK(side >= 29.56f);
+    CHECK(side <= 29.56f + 4.f); // without grossly over-reserving plate space
+    // Separate categories stack their blocks, so the footprint must not shrink when they differ.
+    CHECK(side >= WipeTower::estimate_rib_tower_bbox_side(cube_purges(0), 35.f, 0.21f, 0.4f, 1.5f, 8.f, 0.f, 16.f));
+    CHECK_THAT(WipeTower::estimate_rib_tower_bbox_side({}, 35.f, 0.2f, 0.4f, 1.f, 8.f, 0.f, 16.f), WithinAbs(0.f, 1e-6f));
+}
+
+TEST_CASE("Rib footprint extends the ribs, not the body, below the stability minimum", "[WipeTower]") {
+    // A 10 mm body under a 90 mm print: the ribs stretch to the minimum depth's diagonal, and
+    // the rib width is capped at half the body, so the square grows to minimum + 5 / sqrt(2).
+    const float min_depth = WipeTower::get_limit_depth_by_height(90.f);
+    REQUIRE(min_depth > 10.f);
+    CHECK_THAT(WipeTower::rib_footprint_side(10.f, 10.f, 8.f, 0.f, 90.f), WithinAbs(min_depth + 5.f / std::sqrt(2.f), 1e-4f));
+    // The extra rib length runs along the diagonal, so it shows as its projection on each axis.
+    const float plain = WipeTower::rib_footprint_side(30.f, 30.f, 8.f, 0.f, 5.f);
+    CHECK_THAT(plain, WithinAbs(30.f + 8.f / std::sqrt(2.f), 1e-4f));
+    CHECK_THAT(WipeTower::rib_footprint_side(30.f, 30.f, 8.f, 4.f, 5.f) - plain, WithinAbs(4.f / std::sqrt(2.f), 1e-4f));
+    // A negative extra length cannot pull the ribs inside the diagonal.
+    CHECK_THAT(WipeTower::rib_footprint_side(30.f, 30.f, 8.f, -4.f, 5.f), WithinAbs(plain, 1e-4f));
+    CHECK_THAT(WipeTower::rib_footprint_side(0.f, 30.f, 8.f, 0.f, 5.f), WithinAbs(0.f, 1e-6f));
+}
+
+TEST_CASE("Brim width estimate matches each generator's loop quantization", "[WipeTower]") {
+    // 3 mm configured, 0.4 nozzle, 0.2 first layer: 0.4571 mm spacing, 7 loops. WipeTower2
+    // prints and reports the 7 loops; WipeTower reports half a spacing of line width on top.
+    const float spacing = 0.5f - 0.2f * float(1. - M_PI_4);
+    CHECK_THAT(WipeTower::estimate_brim_real_width(3.f, 0.4f, 0.2f, true), WithinAbs(7.f * spacing, 1e-4f));
+    CHECK_THAT(WipeTower::estimate_brim_real_width(3.f, 0.4f, 0.2f, false), WithinAbs(7.5f * spacing, 1e-4f));
+    CHECK_THAT(WipeTower::estimate_brim_real_width(0.f, 0.4f, 0.2f, true), WithinAbs(0.f, 1e-6f));
+}
+
+// ---------------------------------------------------------------------------------------------
+// "No sparse layers": the compaction rule and the clearance it demands of the plate.
+// ---------------------------------------------------------------------------------------------
+
+// A square of side mm centred on (cx, cy), in bed coordinates.
+static Polygon centered_square(double cx, double cy, double side)
+{
+    const double h = 0.5 * side;
+    Polygon      poly;
+    poly.points = {Point::new_scale(cx - h, cy - h), Point::new_scale(cx + h, cy - h),
+                   Point::new_scale(cx + h, cy + h), Point::new_scale(cx - h, cy + h)};
+    return poly;
+}
+
+static WipeTower::ToolChangeResult make_tcr(int initial_tool, int new_tool, float layer_height)
+{
+    WipeTower::ToolChangeResult tcr{};
+    tcr.initial_tool = initial_tool;
+    tcr.new_tool     = new_tool;
+    tcr.layer_height = layer_height;
+    return tcr;
+}
+
+// A 20 mm square tower at the bed origin, no spiral z-hop, so the keep-out zone is the bare
+// footprint and every distance below is one the test sets.
+static PrintConfig clearance_config()
+{
+    PrintConfig cfg;
+    cfg.extruder_clearance_radius.value       = 40.;
+    cfg.extruder_clearance_dist_to_rod.value  = 20.;
+    cfg.extruder_clearance_height_to_rod.value = 25.;
+    cfg.extruder_clearance_height_to_lid.value = 120.;
+    cfg.nozzle_height.value                   = 5.;
+    cfg.nozzle_diameter.values                = {0.4};
+    cfg.z_hop.values                          = {0.};
+    cfg.travel_slope.values                   = {3.};
+    return cfg;
+}
+
+TEST_CASE("Sparse layers are skipped only when nothing else needs a tower on every layer", "[WipeTower][NoSparseLayers]") {
+    PrintConfig cfg;
+    cfg.timelapse_type.value            = TimelapseType::tlTraditional;
+    cfg.enable_wrapping_detection.value = false;
+
+    cfg.wipe_tower_no_sparse_layers.value = false;
+    CHECK_FALSE(wipe_tower_sparse_layers_skipped(cfg));
+    cfg.wipe_tower_no_sparse_layers.value = true;
+    CHECK(wipe_tower_sparse_layers_skipped(cfg));
+
+    // Both park the nozzle on the tower every layer, so no layer is ever dropped and the option
+    // must read as off everywhere rather than compact in one place and not another.
+    cfg.timelapse_type.value = TimelapseType::tlSmooth;
+    CHECK_FALSE(wipe_tower_sparse_layers_skipped(cfg));
+    cfg.timelapse_type.value            = TimelapseType::tlTraditional;
+    cfg.enable_wrapping_detection.value = true;
+    CHECK_FALSE(wipe_tower_sparse_layers_skipped(cfg));
+}
+
+TEST_CASE("A planned layer is sparse only when its single tool change keeps the filament", "[WipeTower][NoSparseLayers]") {
+    CHECK(wipe_tower_layer_is_sparse({make_tcr(1, 1, 0.2f)}));
+    CHECK_FALSE(wipe_tower_layer_is_sparse({make_tcr(0, 1, 0.2f)}));
+    // A second entry means the layer carries real work whatever the tools are.
+    CHECK_FALSE(wipe_tower_layer_is_sparse({make_tcr(1, 1, 0.2f), make_tcr(1, 1, 0.2f)}));
+    CHECK_FALSE(wipe_tower_layer_is_sparse({}));
+}
+
+TEST_CASE("The compacted tower falls one layer height behind the object per sparse layer", "[WipeTower][NoSparseLayers]") {
+    // Five 0.2 mm layers off a 0.1 mm z offset, the middle two sparse. The object reaches
+    // 0.1 + 5 * 0.2 = 1.1; the tower only grows on the three printed layers, so it ends at
+    // 0.1 + 3 * 0.2 = 0.7 and a sparse layer carries the previous value rather than its own.
+    const std::vector<std::vector<WipeTower::ToolChangeResult>> tool_changes{
+        {make_tcr(0, 1, 0.2f)}, {make_tcr(1, 1, 0.2f)}, {make_tcr(1, 1, 0.2f)},
+        {make_tcr(1, 0, 0.2f)}, {make_tcr(0, 1, 0.2f)}};
+
+    const std::vector<float> tower_z = compute_compacted_wipe_tower_z(tool_changes, 0.1f);
+    REQUIRE(tower_z.size() == tool_changes.size());
+    CHECK_THAT(tower_z[0], WithinAbs(0.3f, 1e-5f));
+    CHECK_THAT(tower_z[1], WithinAbs(0.3f, 1e-5f));
+    CHECK_THAT(tower_z[2], WithinAbs(0.3f, 1e-5f));
+    CHECK_THAT(tower_z[3], WithinAbs(0.5f, 1e-5f));
+    CHECK_THAT(tower_z[4], WithinAbs(0.7f, 1e-5f));
+    CHECK_THAT(1.1f - tower_z.back(), WithinAbs(2 * 0.2f, 1e-5f));
+
+    // Without a base the tower starts at the bed, and an empty layer carries over like a sparse one.
+    const std::vector<float> no_offset = compute_compacted_wipe_tower_z({{make_tcr(0, 1, 0.2f)}, {}}, 0.f);
+    CHECK_THAT(no_offset[0], WithinAbs(0.2f, 1e-5f));
+    CHECK_THAT(no_offset[1], WithinAbs(0.2f, 1e-5f));
+}
+
+TEST_CASE("The tower keep-out zone grows by the spiral z-hop envelope", "[WipeTower][NoSparseLayers]") {
+    PrintConfig   cfg       = clearance_config();
+    const Polygon footprint = centered_square(0., 0., 20.);
+
+    // No lift, no envelope: the zone works on the bare footprint.
+    CHECK_THAT(unscaled(compacted_wipe_tower_zone(cfg, footprint).hull.bounding_box().max.x()), WithinAbs(10., 1e-6));
+
+    // A spiral lift leaves the outline at low z, so it counts as tower. The circle reaches
+    // 2 * lift / (2*pi*atan(slope)) past the outline, matching GCodeWriter: 2*2/(2*pi*atan(3)) = 0.51 mm.
+    cfg.z_hop.values = {2.};
+    const CompactedTowerZone lifted = compacted_wipe_tower_zone(cfg, footprint);
+    CHECK_THAT(unscaled(lifted.hull.bounding_box().max.x()), WithinAbs(10.51, 0.02));
+    CHECK_THAT(unscaled(lifted.hull.bounding_box().min.y()), WithinAbs(-10.51, 0.02));
+    CHECK(diff(Polygons{footprint}, Polygons{lifted.hull}).empty());
+
+    // z_hop is capped at 5 mm by the option, so a taller lift cannot widen the zone further.
+    cfg.z_hop.values = {10.};
+    const double capped = unscaled(compacted_wipe_tower_zone(cfg, footprint).hull.bounding_box().max.x());
+    CHECK_THAT(capped, WithinAbs(10. + 2. * 5. / (2. * M_PI * std::atan(3.)), 0.02));
+
+    // The rod sweeps the whole X axis, so its band is the tower's y span plus half the rod offset.
+    CHECK_THAT(unscaled(lifted.bbox_rod.max.y()), WithinAbs(10.51 + 10., 0.02));
+}
+
+TEST_CASE("An object beside a compacted tower is limited by the nearest part of the toolhead", "[WipeTower][NoSparseLayers]") {
+    const PrintConfig        cfg  = clearance_config();
+    const CompactedTowerZone zone = compacted_wipe_tower_zone(cfg, centered_square(0., 0., 20.));
+
+    // Each side carries half its clearance less 0.1 mm slack, so the two outlines meet when the
+    // objects are a full clearance apart: 2 * (4 - 0.2) / 2 = 3.8 mm for the bare nozzle cone,
+    // 2 * (40 - 0.2) / 2 = 39.8 mm for the head body. A 10 mm object at x leaves a gap of x - 15.
+    const double tall = 50., shortish = 3.;
+
+    // Gap 1 mm, inside the nozzle cone: the object may not rise above the tower at all.
+    const CompactedTowerClearance touching = compacted_wipe_tower_clearance(cfg, zone, centered_square(16., 0., 10.), tall);
+    CHECK_THAT(touching.allowed_rise, WithinAbs(0., 1e-9));
+
+    // Gap 10 mm: clear of the cone but inside the head body, which starts at nozzle_height.
+    const CompactedTowerClearance near_body = compacted_wipe_tower_clearance(cfg, zone, centered_square(25., 0., 10.), tall);
+    CHECK(near_body.near_body);
+    CHECK_THAT(near_body.allowed_rise, WithinAbs(5., 1e-9));
+    CHECK_THAT(near_body.body_clearance, WithinAbs(40., 1e-9));
+
+    // The same spot, but an object that never rises past the cone. The body sits above the cone, so
+    // it cannot reach this object however close it stands, and only the narrow tier applies.
+    const CompactedTowerClearance low = compacted_wipe_tower_clearance(cfg, zone, centered_square(25., 0., 10.), shortish);
+    CHECK_FALSE(low.near_body);
+    CHECK_THAT(low.body_clearance, WithinAbs(4., 1e-9));
+    CHECK_THAT(low.allowed_rise, WithinAbs(25., 1e-9));
+
+    // Gap 55 mm, clear of the head entirely: the rod is the obstacle, since the object shares the
+    // tower's y band and the rod spans the whole x axis however far apart the two stand.
+    const CompactedTowerClearance far_in_band = compacted_wipe_tower_clearance(cfg, zone, centered_square(70., 0., 10.), tall);
+    CHECK_FALSE(far_in_band.near_body);
+    CHECK_THAT(far_in_band.far_clearance, WithinAbs(25., 1e-9));
+    CHECK_THAT(far_in_band.allowed_rise, WithinAbs(25., 1e-9));
+
+    // Out of the band the rod passes over it and only the lid is left.
+    const CompactedTowerClearance out_of_band = compacted_wipe_tower_clearance(cfg, zone, centered_square(70., 60., 10.), tall);
+    CHECK_THAT(out_of_band.allowed_rise, WithinAbs(120., 1e-9));
+}
+
+TEST_CASE("The ring drawn around the tower meets the outline drawn around an offender", "[WipeTower][NoSparseLayers]") {
+    const PrintConfig        cfg  = clearance_config();
+    const CompactedTowerZone zone = compacted_wipe_tower_zone(cfg, centered_square(0., 0., 20.));
+
+    // What the plater draws has to be what the check tested, otherwise a user moves an object until
+    // the outlines part and slicing still refuses the plate. Both halves of the 3.8 mm nozzle
+    // clearance: at a 3 mm gap the rings overlap and the rise limit is zero, at 5 mm neither holds.
+    for (const auto &c : {std::make_pair(18., true), std::make_pair(20., false)}) {
+        DYNAMIC_SECTION("object at x = " << c.first) {
+            const Polygon                 hull      = centered_square(c.first, 0., 10.);
+            const CompactedTowerClearance clearance = compacted_wipe_tower_clearance(cfg, zone, hull, 3.);
+            const Polygons                rings     = compacted_wipe_tower_rings(zone, compacted_tower_body_tier(clearance));
+            const Polygon                 outline   = compacted_wipe_tower_offender_outline(hull, clearance.body_clearance);
+            const bool                    outlines_meet = ! intersection(rings, Polygons{outline}).empty();
+            const bool                    rise_denied   = clearance.allowed_rise < EPSILON;
+            CHECK(outlines_meet == c.second);
+            CHECK(rise_denied == c.second);
+        }
+    }
+}
+
+TEST_CASE("Only the keep-out ring an object is measured against is drawn", "[WipeTower][NoSparseLayers]") {
+    const PrintConfig        cfg  = clearance_config();
+    const CompactedTowerZone zone = compacted_wipe_tower_zone(cfg, centered_square(0., 0., 20.));
+
+    // Drawing the wide ring when no object is judged on it would show a keep-out zone the check can
+    // never trip, so it is added only once some object reaches past the nozzle cone.
+    CHECK(compacted_wipe_tower_rings(zone, false).size() == zone.grown_nozzle.size());
+    CHECK(compacted_wipe_tower_rings(zone, true).size() == zone.grown_nozzle.size() + zone.grown_body.size());
+    CHECK_THAT(unscaled(get_extents(zone.grown_nozzle).max.x()), WithinAbs(10. + 0.5 * (4. - 0.2), 0.02));
+    CHECK_THAT(unscaled(get_extents(zone.grown_body).max.x()), WithinAbs(10. + 0.5 * (40. - 0.2), 0.02));
+}
+
+TEST_CASE("Footprint padding covers the brim and the extrusion half width on each side", "[WipeTower][NoSparseLayers]") {
+    // A nominal outline hulls extrusion centre lines and is re-centred once the real wall is known,
+    // so a line width per side on top of the brim is what keeps an estimate enclosing the real tower.
+    const PrintConfig cfg = clearance_config();
+    CHECK_THAT(compacted_tower_footprint_padding(cfg, 2.), WithinAbs(2. + 2. * 0.4, 1e-9));
+    CHECK_THAT(compacted_tower_footprint_padding(cfg, 0.), WithinAbs(2. * 0.4, 1e-9));
+    // Callers whose outline already carries the brim pass zero, and a negative one cannot shrink it.
+    CHECK_THAT(compacted_tower_footprint_padding(cfg, -5.), WithinAbs(2. * 0.4, 1e-9));
+}

tests/libslic3r/test_wipe_tower_estimate.cpp

@@ -0,0 +1,351 @@
+#include <catch2/catch_all.hpp>
+
+#include "libslic3r/BoundingBox.hpp"
+#include "libslic3r/ClipperUtils.hpp"
+#include "libslic3r/GCode/WipeTower.hpp"
+#include "libslic3r/GCode/WipeTower2.hpp"
+#include "libslic3r/GCode/WipeTowerEstimate.hpp"
+#include "libslic3r/PrintConfig.hpp"
+
+#include <cmath>
+#include <numeric>
+#include <string>
+
+using namespace Slic3r;
+using Catch::Matchers::WithinAbs;
+
+// Rectangle wall, one nozzle, 100 mm3 prime volume on a 50 mm wide tower at 0.2 mm layers: one
+// purge is 10 mm of depth. The flush matrix is off here; the shipped-default case covers it.
+// Built as PresetBundle::full_config builds the GUI's: apply() creates each enum as a
+// ConfigOptionEnumGeneric, where full_print_config() would clone the static defaults'
+// ConfigOptionEnum<T>. The estimate has to read either.
+static DynamicPrintConfig preset_shaped_defaults()
+{
+    DynamicPrintConfig config;
+    config.apply(FullPrintConfig::defaults());
+    return config;
+}
+
+static DynamicPrintConfig make_config(const char *wall_type = "rectangle")
+{
+    DynamicPrintConfig config = preset_shaped_defaults();
+    config.set_key_value("prime_tower_width", new ConfigOptionFloat(50.));
+    config.set_key_value("prime_volume", new ConfigOptionFloat(100.));
+    config.set_key_value("filament_prime_volume", new ConfigOptionFloats({100.}));
+    config.set_key_value("filament_adhesiveness_category", new ConfigOptionInts({0}));
+    config.set_key_value("prime_tower_infill_gap", new ConfigOptionPercent(100.));
+    config.set_key_value("wipe_tower_extra_spacing", new ConfigOptionPercent(100.));
+    config.set_key_value("prime_tower_brim_width", new ConfigOptionFloat(3.));
+    config.set_deserialize_strict("wipe_tower_wall_type", wall_type);
+    config.set_key_value("wipe_tower_rib_width", new ConfigOptionFloat(8.));
+    config.set_key_value("wipe_tower_extra_rib_length", new ConfigOptionFloat(0.));
+    config.set_key_value("nozzle_diameter", new ConfigOptionFloats({0.4}));
+    config.set_key_value("initial_layer_print_height", new ConfigOptionFloat(0.2));
+    config.set_deserialize_strict("timelapse_type", "0");
+    config.set_key_value("enable_wrapping_detection", new ConfigOptionBool(false));
+    config.set_key_value("raft_layers", new ConfigOptionInt(0));
+    config.set_key_value("purge_in_prime_tower", new ConfigOptionBool(false));
+    config.set_key_value("single_extruder_multi_material", new ConfigOptionBool(false));
+    return config;
+}
+
+static std::vector<unsigned int> filaments(size_t count)
+{
+    std::vector<unsigned int> ids(count);
+    std::iota(ids.begin(), ids.end(), 0u);
+    return ids;
+}
+
+// The first `count` filaments on the given planner; Type2 unless a case says otherwise.
+static WipeTowerFootprint estimate(const ConfigBase &config, size_t count, double layer_height, double height, WipeTowerType type = WipeTowerType::Type2)
+{
+    return estimate_wipe_tower_footprint(config, type, filaments(count), layer_height, height);
+}
+
+// What both planners print for a 3 mm brim at 0.4 nozzle and 0.2 first layer (0.4571 mm loops).
+static double printed_brim(double configured, WipeTowerType type)
+{
+    return WipeTower::estimate_brim_real_width(float(configured), 0.4f, 0.2f, type == WipeTowerType::Type2);
+}
+
+TEST_CASE("A rectangle wall tower is sized by the purge volume", "[WipeTowerEstimate]") {
+    const DynamicPrintConfig config = make_config();
+    // Three filaments purge twice per layer; a 5 mm object keeps the stability floor at 5 mm.
+    const WipeTowerFootprint fp = estimate(config, 3, 0.2, 5.);
+    CHECK_THAT(fp.width, WithinAbs(50., 1e-9));
+    CHECK_THAT(fp.depth, WithinAbs(20., 1e-9));
+    CHECK_THAT(fp.height, WithinAbs(5., 1e-9));
+    CHECK_THAT(fp.brim_width, WithinAbs(printed_brim(3., WipeTowerType::Type2), 1e-6));
+    // Thinner layers need more depth for the same volume.
+    CHECK_THAT(estimate(config, 3, 0.1, 5.).depth, WithinAbs(40., 1e-9));
+}
+
+TEST_CASE("Each planner spaces its purge lines by its own option", "[WipeTowerEstimate]") {
+    // Type2 reads wipe_tower_extra_spacing and Type1 prime_tower_infill_gap; neither sees the
+    // other's key. Type2's extra flow cancels out of its depth.
+    DynamicPrintConfig config = make_config();
+    config.set_key_value("wipe_tower_extra_flow", new ConfigOptionPercent(250.));
+    CHECK_THAT(estimate(config, 3, 0.2, 5.).depth, WithinAbs(20., 1e-9));
+    config.set_key_value("wipe_tower_extra_spacing", new ConfigOptionPercent(150.));
+    CHECK_THAT(estimate(config, 3, 0.2, 5.).depth, WithinAbs(30., 1e-9));
+    const double type1_spaced = estimate(config, 3, 0.2, 5., WipeTowerType::Type1).depth;
+    config.set_key_value("prime_tower_infill_gap", new ConfigOptionPercent(150.));
+    CHECK_THAT(estimate(config, 3, 0.2, 5.).depth, WithinAbs(30., 1e-9));
+    // Type1 stacks whole lines behind one 0.5 mm perimeter width, so only the stack scales.
+    CHECK_THAT(estimate(config, 3, 0.2, 5., WipeTowerType::Type1).depth - 0.5, WithinAbs(1.5 * (type1_spaced - 0.5), 1e-6));
+}
+
+TEST_CASE("Type1 sizes the tower from each filament's own prime volume", "[WipeTowerEstimate]") {
+    // The Bambu P1S project of the WipeTower cases: 30 and 45 mm3 in two categories on a 35 mm
+    // tower at 0.21 mm, 150 % gap, is 18.5 mm of stacked blocks (11 mm sharing one category).
+    DynamicPrintConfig config = make_config();
+    config.set_key_value("prime_tower_width", new ConfigOptionFloat(35.));
+    config.set_key_value("prime_tower_infill_gap", new ConfigOptionPercent(150.));
+    config.set_key_value("initial_layer_print_height", new ConfigOptionFloat(0.21));
+    config.set_key_value("filament_prime_volume", new ConfigOptionFloats({30., 45.}));
+    config.set_key_value("filament_adhesiveness_category", new ConfigOptionInts({100, 0}));
+    const std::vector<WipeTower::PurgeEstimate> purges{{30.f, 100}, {45.f, 0}};
+    const double blocks = WipeTower::estimate_tower_blocks_depth(purges, 35.f, 0.21f, 0.4f, 1.5f);
+    REQUIRE_THAT(blocks, WithinAbs(18.5, 0.01));
+    CHECK_THAT(estimate(config, 2, 0.21, 5., WipeTowerType::Type1).depth, WithinAbs(blocks, 1e-4));
+    // The ids pick the volumes, so their order does not matter and a lone filament has no purge.
+    CHECK_THAT(estimate_wipe_tower_footprint(config, WipeTowerType::Type1, {1, 0}, 0.21, 5.).depth, WithinAbs(blocks, 1e-4));
+    CHECK_THAT(estimate(config, 1, 0.21, 5., WipeTowerType::Type1).depth, WithinAbs(0., 1e-9));
+    config.set_key_value("filament_adhesiveness_category", new ConfigOptionInts({0, 0}));
+    CHECK_THAT(estimate(config, 2, 0.21, 5., WipeTowerType::Type1).depth, WithinAbs(11., 0.01));
+    // A rib wall squares the same stack.
+    config.set_deserialize_strict("wipe_tower_wall_type", "rib");
+    const WipeTowerFootprint rib = estimate(config, 2, 0.21, 5., WipeTowerType::Type1);
+    CHECK_THAT(rib.width, WithinAbs(rib.depth, 1e-9));
+    CHECK_THAT(rib.depth, WithinAbs(WipeTower::estimate_rib_tower_bbox_side({{30.f, 0}, {45.f, 0}}, 35.f, 0.21f, 0.4f, 1.5f, 8.f, 0.f, 5.f), 1e-4));
+}
+
+TEST_CASE("A second nozzle adds the ramming of one nozzle change per layer", "[WipeTowerEstimate]") {
+    // Two filaments on two nozzles: the tool order crosses once per layer, and Type1 rams 10 mm
+    // of filament as three 1.0 mm nozzle-change lines (see the WipeTower case).
+    DynamicPrintConfig config = make_config();
+    config.set_key_value("nozzle_diameter", new ConfigOptionFloats({0.4, 0.4}));
+    config.set_key_value("filament_change_length", new ConfigOptionFloats({10., 10.}));
+    config.set_key_value("filament_diameter", new ConfigOptionFloats({1.75, 1.75}));
+    config.set_key_value("filament_map", new ConfigOptionInts({1, 1}));
+    const double same_nozzle = estimate(config, 2, 0.2, 5., WipeTowerType::Type1).depth;
+    config.set_key_value("filament_map", new ConfigOptionInts({1, 2}));
+    CHECK_THAT(estimate(config, 2, 0.2, 5., WipeTowerType::Type1).depth - same_nozzle, WithinAbs(3., 1e-4));
+}
+
+TEST_CASE("The tower is sized for the first layer when it is the thinnest", "[WipeTowerEstimate]") {
+    // Both planners reserve the worst layer: a 0.28 mm print with a 0.2 mm first layer needs
+    // the 0.2 mm depth, while a thicker first layer changes nothing.
+    DynamicPrintConfig config = make_config();
+    const double at_thinnest = estimate(config, 3, 0.2, 5.).depth;
+    CHECK_THAT(estimate(config, 3, 0.28, 5.).depth, WithinAbs(at_thinnest, 1e-9));
+    config.set_key_value("initial_layer_print_height", new ConfigOptionFloat(0.3));
+    CHECK(estimate(config, 3, 0.28, 5.).depth < at_thinnest);
+}
+
+TEST_CASE("Object height sets the stability floor and the auto brim", "[WipeTowerEstimate]") {
+    DynamicPrintConfig config = make_config();
+    // Two filaments purge once: 10 mm, lifted to the 20 mm floor of a 100 mm tower.
+    CHECK_THAT(estimate(config, 2, 0.2, 100.).depth, WithinAbs(20., 1e-9));
+    config.set_key_value("prime_tower_brim_width", new ConfigOptionFloat(-1.));
+    const double auto_brim = WipeTower::get_auto_brim_by_height(50.f);
+    CHECK_THAT(estimate(config, 2, 0.2, 50.).brim_width, WithinAbs(printed_brim(auto_brim, WipeTowerType::Type2), 1e-6));
+    CHECK_THAT(estimate(config, 2, 0.2, 50., WipeTowerType::Type1).brim_width, WithinAbs(printed_brim(auto_brim, WipeTowerType::Type1), 1e-6));
+}
+
+TEST_CASE("A single filament only gets a tower when one is printed anyway", "[WipeTowerEstimate]") {
+    DynamicPrintConfig config = make_config();
+    CHECK_THAT(estimate(config, 1, 0.2, 100.).depth, WithinAbs(0., 1e-9));
+    CHECK_THAT(estimate(config, 0, 0.2, 100.).width, WithinAbs(0., 1e-9));
+
+    // Wrapping detection prints a tower on the first layers whatever the filament count: the
+    // Type1 planner's fixed 10 mm, the stability floor otherwise.
+    config.set_key_value("enable_wrapping_detection", new ConfigOptionBool(true));
+    CHECK_THAT(estimate(config, 1, 0.2, 100.).depth, WithinAbs(20., 1e-9));
+    CHECK_THAT(estimate(config, 1, 0.2, 100., WipeTowerType::Type1).depth, WithinAbs(WipeTower::get_wrapping_detection_depth(), 1e-9));
+    config.set_key_value("enable_wrapping_detection", new ConfigOptionBool(false));
+
+    // A raft is not one of them: normalize_fdm_2 clears enable_prime_tower for a plate that
+    // purges one filament unless smooth timelapse or wrapping detection is on, so a raft
+    // alone leaves no tower to reserve for.
+    config.set_key_value("raft_layers", new ConfigOptionInt(3));
+    CHECK_THAT(estimate(config, 1, 0.2, 100.).depth, WithinAbs(0., 1e-9));
+    config.set_key_value("raft_layers", new ConfigOptionInt(0));
+
+    config.set_deserialize_strict("timelapse_type", "1");
+    // A tower printed with no tool change is exactly the planner's idle depth: there is
+    // nothing to purge, and WipeTower2 sizes it at the stability floor.
+    CHECK_THAT(estimate(config, 1, 0.2, 100.).depth, WithinAbs(20., 1e-9));
+    CHECK_THAT(estimate(config, 1, 0.2, 5.).depth, WithinAbs(WipeTower::get_limit_depth_by_height(5.f), 1e-9));
+}
+
+TEST_CASE("A tool change reserves a tower even with nothing to purge", "[WipeTowerEstimate]") {
+    // The purge volumes are configurable down to zero, but the tool changes are still printed
+    // on the tower and both planners still floor it - so the estimate has to floor it too.
+    // Type1 plans per filament and already reserves one; Type2 has only the volume to go on.
+    const double     height = GENERATE(5., 100.);
+    const float      floor  = WipeTower::get_limit_depth_by_height(float(height));
+    const char      *wall   = GENERATE("rectangle", "rib");
+    DynamicPrintConfig config = make_config(wall);
+    config.set_key_value("prime_volume", new ConfigOptionFloat(0.));
+    config.set_key_value("filament_prime_volume", new ConfigOptionFloats({0.}));
+
+    CHECK(estimate(config, 3, 0.2, height, WipeTowerType::Type2).depth >= floor);
+    CHECK(estimate(config, 3, 0.2, height, WipeTowerType::Type1).depth >= floor);
+    // Still nothing for a lone filament with no other reason.
+    CHECK_THAT(estimate(config, 1, 0.2, height, WipeTowerType::Type2).depth, WithinAbs(0., 1e-9));
+    CHECK_THAT(estimate(config, 1, 0.2, height, WipeTowerType::Type1).depth, WithinAbs(0., 1e-9));
+}
+
+TEST_CASE("Both wall types agree on whether there is a tower at all", "[WipeTowerEstimate]") {
+    // A wall type may only change the shape of the tower, never whether one is reserved:
+    // reporting no tower for one that is built collapses the validation hull to a point.
+    const double height = GENERATE(5., 100.);
+    DynamicPrintConfig rect = make_config();
+    DynamicPrintConfig rib  = make_config("rib");
+
+    // No tool change and nothing else that prints a tower - neither wall type reserves one.
+    CHECK_THAT(estimate(rect, 1, 0.2, height).depth, WithinAbs(0., 1e-9));
+    CHECK_THAT(estimate(rib, 1, 0.2, height).depth, WithinAbs(0., 1e-9));
+
+    // Not even on a dual-nozzle printer, where a lone filament still needs no purge.
+    rect.set_key_value("nozzle_diameter", new ConfigOptionFloats({0.4, 0.4}));
+    rib.set_key_value("nozzle_diameter", new ConfigOptionFloats({0.4, 0.4}));
+    CHECK_THAT(estimate(rect, 1, 0.2, height).depth, WithinAbs(0., 1e-9));
+    CHECK_THAT(estimate(rib, 1, 0.2, height).depth, WithinAbs(0., 1e-9));
+
+    // With a tool change both reserve one, and both respect the stability floor.
+    CHECK(estimate(rect, 2, 0.2, height).depth >= WipeTower::get_limit_depth_by_height(float(height)));
+    CHECK(estimate(rib, 2, 0.2, height).depth >= WipeTower::get_limit_depth_by_height(float(height)));
+}
+
+TEST_CASE("A rib wall squares the tower and caps the rib width", "[WipeTowerEstimate]") {
+    DynamicPrintConfig config = make_config("rib");
+    // sqrt(200 / 0.2) = 31.62 mm square, plus the 8 mm rib bulge along the diagonal.
+    const double body = std::sqrt(1000.);
+    WipeTowerFootprint fp = estimate(config, 3, 0.2, 5.);
+    CHECK_THAT(fp.depth, WithinAbs(8. / std::sqrt(2.) + body, 1e-5));
+    CHECK_THAT(fp.width, WithinAbs(fp.depth, 1e-9));
+    // The extra rib length runs along the diagonal and grows the footprint by its projection.
+    config.set_key_value("wipe_tower_extra_rib_length", new ConfigOptionFloat(4.));
+    CHECK_THAT(estimate(config, 3, 0.2, 5.).depth, WithinAbs((8. + 4.) / std::sqrt(2.) + body, 1e-5));
+    // A tiny tower caps the rib width at half its depth: 5 mm body, 2.5 mm rib.
+    config.set_key_value("wipe_tower_extra_rib_length", new ConfigOptionFloat(0.));
+    config.set_key_value("prime_volume", new ConfigOptionFloat(5.));
+    CHECK_THAT(estimate(config, 2, 0.2, 5.).depth, WithinAbs(2.5 / std::sqrt(2.) + 5., 1e-5));
+}
+
+TEST_CASE("Every wall and tower type is read the same from a preset and a static config", "[WipeTowerEstimate]") {
+    // The GUI, arrange and the CLI pass a DynamicPrintConfig whose enums are
+    // ConfigOptionEnumGeneric; Print passes a static config whose enums are ConfigOptionEnum<T>.
+    // Both the wall type and the planner selection are read by value, so both give the same shape.
+    const char *wall_type  = GENERATE("rectangle", "cone", "rib");
+    const char *tower_type = GENERATE("type1", "type2");
+    DynamicPrintConfig preset = make_config(wall_type);
+    preset.set_deserialize_strict("wipe_tower_type", tower_type);
+    REQUIRE(dynamic_cast<const ConfigOptionEnumGeneric *>(preset.option("wipe_tower_wall_type")) != nullptr);
+
+    FullPrintConfig static_config;
+    static_config.apply(preset, true);
+    REQUIRE(static_config.wipe_tower_wall_type.serialize() == wall_type);
+    REQUIRE(static_config.wipe_tower_type.serialize() == tower_type);
+
+    const WipeTowerType type = resolve_wipe_tower_type(preset);
+    CHECK(type == (std::string(tower_type) == "type1" ? WipeTowerType::Type1 : WipeTowerType::Type2));
+    CHECK(resolve_wipe_tower_type(static_config) == type);
+
+    // Three filaments purge twice per layer on a 5 mm object.
+    const WipeTowerFootprint fp          = estimate(preset, 3, 0.2, 5., type);
+    const WipeTowerFootprint from_static = estimate(static_config, 3, 0.2, 5., type);
+    CHECK(fp.depth > 0.);
+    if (std::string(wall_type) == "rib")
+        CHECK_THAT(fp.width, WithinAbs(fp.depth, 1e-9));
+    else
+        CHECK_THAT(fp.width, WithinAbs(50., 1e-9));
+    CHECK_THAT(from_static.width, WithinAbs(fp.width, 1e-9));
+    CHECK_THAT(from_static.depth, WithinAbs(fp.depth, 1e-9));
+    CHECK_THAT(from_static.brim_width, WithinAbs(fp.brim_width, 1e-9));
+
+    // Smooth timelapse is the other enum the estimate reads: a lone filament gets a tower
+    // through both storages too.
+    preset.set_deserialize_strict("timelapse_type", "1");
+    static_config.apply(preset, true);
+    CHECK(estimate(preset, 1, 0.2, 5., type).depth > 0.);
+    CHECK(estimate(static_config, 1, 0.2, 5., type).depth > 0.);
+}
+
+TEST_CASE("The first-layer outline bulges only for a Type2 cone wall", "[WipeTowerEstimate]") {
+    // Read off a preset-shaped config, whose enums are ConfigOptionEnumGeneric: a cast to
+    // ConfigOptionEnum<T> sees no wall type there and would never find the cone.
+    DynamicPrintConfig config = make_config("cone");
+    config.set_key_value("wipe_tower_cone_angle", new ConfigOptionFloat(25.));
+    REQUIRE(dynamic_cast<const ConfigOptionEnumGeneric *>(config.option("wipe_tower_wall_type")) != nullptr);
+    const Polygon box = Polygon::new_scale({{0., 0.}, {35., 0.}, {35., 20.}, {0., 20.}});
+    auto is_box = [&box](const Polygon &outline) { return diff(Polygons{outline}, Polygons{box}).empty(); };
+
+    // A 25-degree cone on a 100 mm tower has a 22 mm base radius, past the 10 mm half-depth.
+    const Polygon cone = estimate_wipe_tower_first_layer_outline(config, WipeTowerType::Type2, 35., 20., 100.);
+    CHECK(unscaled(get_extents(cone).max.y()) > 20. + 1.);
+    CHECK(diff(Polygons{box}, Polygons{cone}).empty());
+    // Type1 ignores the cone option, and the other wall types have no cone.
+    CHECK(is_box(estimate_wipe_tower_first_layer_outline(config, WipeTowerType::Type1, 35., 20., 100.)));
+    for (const char *wall_type : {"rectangle", "rib"}) {
+        config.set_deserialize_strict("wipe_tower_wall_type", wall_type);
+        CHECK(is_box(estimate_wipe_tower_first_layer_outline(config, WipeTowerType::Type2, 35., 20., 100.)));
+    }
+    // The static config Print holds gives the same outline.
+    config.set_deserialize_strict("wipe_tower_wall_type", "cone");
+    FullPrintConfig static_config;
+    static_config.apply(config, true);
+    const Polygon from_static = estimate_wipe_tower_first_layer_outline(static_config, WipeTowerType::Type2, 35., 20., 100.);
+    CHECK(from_static.points == cone.points);
+}
+
+TEST_CASE("A Bambu Lab printer always gets the Type1 planner", "[WipeTowerEstimate]") {
+    DynamicPrintConfig config = make_config();
+    config.set_deserialize_strict("wipe_tower_type", "type2");
+    config.set_key_value("printer_model", new ConfigOptionString("Bambu Lab X1 Carbon"));
+    CHECK(resolve_wipe_tower_type(config) == WipeTowerType::Type1);
+    config.set_key_value("printer_model", new ConfigOptionString("Voron 2.4"));
+    CHECK(resolve_wipe_tower_type(config) == WipeTowerType::Type2);
+    config.erase("wipe_tower_type");
+    CHECK(resolve_wipe_tower_type(config) == WipeTowerType::Type2);
+}
+
+TEST_CASE("A dual nozzle purges every filament plus the filament change", "[WipeTowerEstimate]") {
+    DynamicPrintConfig config = make_config();
+    config.set_key_value("nozzle_diameter", new ConfigOptionFloats({0.4, 0.4}));
+    config.set_key_value("filament_change_length", new ConfigOptionFloats({10., 10.}));
+    config.set_key_value("filament_diameter", new ConfigOptionFloats({1.75, 1.75}));
+    // Two purges of 100 mm3 plus one 10 mm filament change: (200 + 10 * pi * 1.75^2 / 4) / (0.2 * 50).
+    const double change_volume = 10. * PI * 1.75 * 1.75 / 4.;
+    CHECK_THAT(estimate(config, 2, 0.2, 5.).depth, WithinAbs((200. + change_volume) / 10., 1e-9));
+}
+
+TEST_CASE("The shipped defaults size the tower from the flush matrix", "[WipeTowerEstimate]") {
+    // Both keys default to true, so the shipped configuration purges the flush volumes rather
+    // than the prime volume, with no infill gap on top - the flush volumes already hold it.
+    DynamicPrintConfig config = preset_shaped_defaults();
+    REQUIRE(config.opt_bool("purge_in_prime_tower"));
+    REQUIRE(config.opt_bool("single_extruder_multi_material"));
+    config.set_key_value("prime_tower_width", new ConfigOptionFloat(50.));
+    config.set_deserialize_strict("wipe_tower_wall_type", "rectangle");
+    config.set_key_value("nozzle_diameter", new ConfigOptionFloats({0.4}));
+
+    const double flush_volume = WipeTower2::estimate_semm_flush_volume(config, 2);
+    const double expected     = std::max(double(WipeTower::get_limit_depth_by_height(5.f)), flush_volume / (0.2 * 50.));
+    CHECK_THAT(estimate(config, 2, 0.2, 5.).depth, WithinAbs(expected, 1e-6));
+}
+
+TEST_CASE("A config missing a tower key falls back to that key's default", "[WipeTowerEstimate]") {
+    // The signature takes any ConfigBase: an absent key must read as its declared default.
+    const DynamicPrintConfig full = make_config();
+    DynamicPrintConfig       partial = full;
+    partial.erase("wipe_tower_extra_spacing");
+    REQUIRE(partial.option("wipe_tower_extra_spacing") == nullptr);
+
+    DynamicPrintConfig defaulted = full;
+    defaulted.set_key_value("wipe_tower_extra_spacing",
+                            print_config_def.get("wipe_tower_extra_spacing")->default_value->clone());
+    CHECK_THAT(estimate(partial, 3, 0.2, 5.).depth, WithinAbs(estimate(defaulted, 3, 0.2, 5.).depth, 1e-9));
+}

tests/slic3rutils/CMakeLists.txt

@@ -55,6 +55,18 @@ elseif (APPLE)
         COMMENT "Copying Python runtime for macOS plugin host API tests"
         VERBATIM
     )
+elseif (FLATPAK)
+    # Same <testdir>/python home as WIN32/APPLE; symlink since /app/libpython
+    # already ships in the flatpak (the test exe links libpython3.12.so from it).
+    add_custom_command(TARGET ${_TEST_NAME}_tests POST_BUILD
+        COMMAND ${CMAKE_COMMAND} -E rm -rf
+            "$<TARGET_FILE_DIR:${_TEST_NAME}_tests>/python"
+        COMMAND ${CMAKE_COMMAND} -E create_symlink
+            "${CMAKE_PREFIX_PATH}/libpython"
+            "$<TARGET_FILE_DIR:${_TEST_NAME}_tests>/python"
+        COMMENT "Linking Python runtime for flatpak plugin host API tests"
+        VERBATIM
+    )
 endif()
 
 orcaslicer_discover_tests(${_TEST_NAME}_tests)

tests/test_utils.hpp

@@ -176,4 +176,22 @@ inline void write_debug_stream([[maybe_unused]] const std::string &name, [[maybe
 #endif
 }
 
+// Changes the working directory and restores the previous one on scope exit, including when an
+// assertion throws. It is process wide state shared with every other test.
+class ScopedWorkingDirectory
+{
+public:
+    explicit ScopedWorkingDirectory(const boost::filesystem::path &dir)
+        : m_previous(boost::filesystem::current_path())
+    {
+        boost::filesystem::current_path(dir);
+    }
+    ~ScopedWorkingDirectory() { boost::system::error_code ec; boost::filesystem::current_path(m_previous, ec); }
+    ScopedWorkingDirectory(const ScopedWorkingDirectory &) = delete;
+    ScopedWorkingDirectory &operator=(const ScopedWorkingDirectory &) = delete;
+
+private:
+    boost::filesystem::path m_previous;
+};
+
 #endif // SLIC3R_TEST_UTILS