M8a: assembly mates — Fastened + Planar (recipe v3)

An assembly is a multi-body document. An instance is already expressible as
Transform with xf_copy=true, and a mate connector is already a CoordSys
feature, so this adds exactly one feature type: Mate.

No constraint solver. A mate rigidly transforms the body carrying connector B
so that B's frame lands on connector A's, applied in feature order like every
other feature. Chains resolve by composition; closed kinematic loops do not
converge (last mate wins) and are out of scope.

The vendored SolveSpace in src/libslic3r/slvs/ was evaluated for 3D extension
and rejected: it is built and linked but has zero callers, and SketchEngine's
solver is hand-rolled. Extending it would mean adopting a dependency to write
more code than the alternative.

- CadFeatureType::Mate appended; six fields (mate_kind, mate_cs_a, mate_cs_b,
  mate_offset, mate_angle, mate_flip) appended at the END of both cereal lists
- SNAPORCA_CAD_RECIPE_VERSION 2 -> 3; v2 blobs are rejected, as by design there
  is no migration path. Golden fixture renamed to cad_recipe_v3.bin and
  regenerated once, extended with two CoordSys + one Mate so the new fields are
  tripwired by the field-order assertions
- datum_frame() extracted from resolve_datum_coordsys() so a mate can resolve
  its connectors against the in-progress bodies vector during replay
- apply_mate dispatched early-return, so Mate is deliberately absent from
  starts_new (unreachable for that dispatch style)
- Planar: the degenerate branch splits on the sign of zB.z_target — antiparallel
  needs a 180 deg rotation about a perpendicular axis, which an earlier revision
  silently skipped, leaving the body's normal inverted
- MCP: mate command, named bare to match the other 38 methods

Drive-by: feature_type_name() was missing Mirror, ThickenSurface, SurfaceOffset,
SurfaceLoft and SurfaceFill, which reported as "Unknown" to MCP clients.

Suite 122 cases / 1741 assertions green. Note that kernel-test.sh builds only
libslic3r_tests, so McpControl.cpp is reviewed but not compiled here.

Co-Authored-By: Claude Opus 5 (1M context) <noreply@anthropic.com>
This commit is contained in:
Tommaso Bianchi
2026-07-25 10:51:22 +02:00
co-authored by Claude Opus 5
parent 9c28be5860
commit b13ca01ccc
6 changed files with 838 additions and 47 deletions
+615 -2
View File
@@ -3567,6 +3567,17 @@ static CadDocument make_golden_doc_v1()
doc.add_sketch_entities(ge, SketchPlane::XY(), "Sketch_Ctor");
}
// ---- Mate connectors: two CoordSys features with distinctive non-default values ----
int cs_idx_a = doc.add_coordsys(CoordSysType::PointWorld, Vec3d(11, 12, 13), "CS_MateA");
doc.features[cs_idx_a].coordsys_body = 0;
doc.features[cs_idx_a].coordsys_x_hint = Vec3d(0.1, 0.2, 0.9);
int cs_idx_b = doc.add_coordsys(CoordSysType::PointWorld, Vec3d(14, 15, 16), "CS_MateB");
doc.features[cs_idx_b].coordsys_body = 1;
doc.features[cs_idx_b].coordsys_x_hint = Vec3d(0.6, 0.7, 0.3);
// ---- Mate: Fastened with all six fields carrying distinctive non-defaults ----
doc.add_mate(1, cs_idx_a, cs_idx_b, 7.25, 33.0, true, "GoldenMate");
return doc;
}
@@ -3578,7 +3589,7 @@ TEST_CASE("regenerate golden recipe fixture", "[.regen]")
auto blob = doc.serialize_recipe();
REQUIRE_FALSE(blob.empty());
std::string path = std::string(TEST_DATA_DIR) + "/cad_recipe_v2.bin";
std::string path = std::string(TEST_DATA_DIR) + "/cad_recipe_v3.bin";
std::ofstream ofs(path, std::ios::binary);
REQUIRE(ofs.is_open());
ofs.write(blob.data(), static_cast<std::streamsize>(blob.size()));
@@ -3592,7 +3603,7 @@ TEST_CASE("golden recipe v1 still deserialises", "[CadDocument]")
using Catch::Matchers::WithinAbs;
// Read the golden blob from disk
std::string path = std::string(TEST_DATA_DIR) + "/cad_recipe_v2.bin";
std::string path = std::string(TEST_DATA_DIR) + "/cad_recipe_v3.bin";
std::ifstream ifs(path, std::ios::binary);
REQUIRE(ifs.is_open());
std::string blob((std::istreambuf_iterator<char>(ifs)),
@@ -3868,6 +3879,16 @@ TEST_CASE("golden recipe v1 still deserialises", "[CadDocument]")
REQUIRE(f.project_face == 0);
REQUIRE(f.project_edges == e.project_edges);
}
// Mate
if (f.type == CadFeatureType::Mate && e.name == "GoldenMate") {
REQUIRE(f.mate_kind == 1);
REQUIRE(f.mate_cs_a == e.mate_cs_a);
REQUIRE(f.mate_cs_b == e.mate_cs_b);
REQUIRE_THAT(f.mate_offset, WithinAbs(7.25, 1e-9));
REQUIRE_THAT(f.mate_angle, WithinAbs(33.0, 1e-9));
REQUIRE(f.mate_flip == true);
}
}
// --- Layer 2: geometry check (optional — only if the document recomputes) ---
@@ -4874,3 +4895,595 @@ TEST_CASE("surface-loft round-trip serialize/deserialize", "[CadDocument][surfac
REQUIRE_THAT(double(fy1), WithinAbs(double(oy1), 1e-6));
REQUIRE_THAT(double(fz1), WithinAbs(double(oz1), 1e-6));
}
// --- Mate tests (M8a) ---
TEST_CASE("fastened mate with zero offset/angle", "[CadDocument][mate]")
{
using Catch::Matchers::WithinAbs;
CadDocument doc;
int sk_box = doc.add_sketch(SketchShape::Rectangle, SketchPlane::XY(), 10, 10, 0, "Box");
doc.add_extrude(sk_box, 5.0, false, BooleanMode::New, "BoxExt");
REQUIRE(doc.recompute());
REQUIRE(doc.error.empty());
int cs_fixed = doc.add_coordsys(CoordSysType::PointWorld, Vec3d(5, 5, 5), "CS_Fixed");
doc.features[cs_fixed].coordsys_body = 0;
REQUIRE(doc.recompute());
REQUIRE(doc.error.empty());
int sk_cyl = doc.add_sketch(SketchShape::Circle, SketchPlane::XY(), 0, 0, 3, "Cyl");
doc.add_extrude(sk_cyl, 10.0, false, BooleanMode::New, "CylExt");
REQUIRE(doc.recompute());
REQUIRE(doc.error.empty());
REQUIRE(doc.bodies.size() == 2);
int cs_moving = doc.add_coordsys(CoordSysType::PointWorld, Vec3d(0, 0, 5), "CS_Moving");
doc.features[cs_moving].coordsys_body = 1;
REQUIRE(doc.recompute());
REQUIRE(doc.error.empty());
int mi = doc.add_mate(0, cs_fixed, cs_moving, 0.0, 0.0, false, "Mate");
REQUIRE(mi >= 0);
REQUIRE(doc.recompute());
REQUIRE(doc.error.empty());
GProp_GProps props;
BRepGProp::VolumeProperties(doc.bodies[1].shape, props);
gp_Pnt com = props.CentreOfMass();
REQUIRE_THAT(double(com.X()), WithinAbs(5.0, 1e-4));
REQUIRE_THAT(double(com.Y()), WithinAbs(5.0, 1e-4));
REQUIRE_THAT(double(com.Z()), WithinAbs(5.0, 1e-4));
}
TEST_CASE("fastened mate with offset", "[CadDocument][mate]")
{
using Catch::Matchers::WithinAbs;
CadDocument doc;
int sk = doc.add_sketch(SketchShape::Rectangle, SketchPlane::XY(), 10, 10, 0, "Box");
doc.add_extrude(sk, 5.0, false, BooleanMode::New, "E");
REQUIRE(doc.recompute());
REQUIRE(doc.error.empty());
int cs_fixed = doc.add_coordsys(CoordSysType::PointWorld, Vec3d(5, 5, 5), "CS_Fixed");
doc.features[cs_fixed].coordsys_body = 0;
REQUIRE(doc.recompute());
REQUIRE(doc.error.empty());
int sk2 = doc.add_sketch(SketchShape::Circle, SketchPlane::XY(), 0, 0, 3, "Cyl");
doc.add_extrude(sk2, 10.0, false, BooleanMode::New, "CylExt");
REQUIRE(doc.recompute());
REQUIRE(doc.error.empty());
int cs_moving = doc.add_coordsys(CoordSysType::PointWorld, Vec3d(0, 0, 5), "CS_Moving");
doc.features[cs_moving].coordsys_body = 1;
REQUIRE(doc.recompute());
REQUIRE(doc.error.empty());
doc.add_mate(0, cs_fixed, cs_moving, 7.0, 0.0, false, "Mate");
REQUIRE(doc.recompute());
REQUIRE(doc.error.empty());
GProp_GProps props;
BRepGProp::VolumeProperties(doc.bodies[1].shape, props);
gp_Pnt com = props.CentreOfMass();
REQUIRE_THAT(double(com.Z()), WithinAbs(12.0, 1e-4));
}
TEST_CASE("fastened mate with angle", "[CadDocument][mate]")
{
using Catch::Matchers::WithinAbs;
CadDocument doc;
int sk = doc.add_sketch(SketchShape::Rectangle, SketchPlane::XY(), 10, 10, 0, "Box");
doc.add_extrude(sk, 5.0, false, BooleanMode::New, "E");
REQUIRE(doc.recompute());
REQUIRE(doc.error.empty());
int cs_fixed = doc.add_coordsys(CoordSysType::PointWorld, Vec3d(5, 5, 5), "CS_Fixed");
doc.features[cs_fixed].coordsys_body = 0;
REQUIRE(doc.recompute());
REQUIRE(doc.error.empty());
int sk2 = doc.add_sketch(SketchShape::Circle, SketchPlane::XY(), 0, 0, 3, "Cyl");
doc.add_extrude(sk2, 10.0, false, BooleanMode::New, "CylExt");
REQUIRE(doc.recompute());
REQUIRE(doc.error.empty());
int cs_moving = doc.add_coordsys(CoordSysType::PointWorld, Vec3d(0, 0, 5), "CS_Moving");
doc.features[cs_moving].coordsys_x_hint = Vec3d(1, 0, 0);
doc.features[cs_moving].coordsys_body = 1;
REQUIRE(doc.recompute());
REQUIRE(doc.error.empty());
doc.add_mate(0, cs_fixed, cs_moving, 0.0, 90.0, false, "Mate");
REQUIRE(doc.recompute());
REQUIRE(doc.error.empty());
GProp_GProps props;
BRepGProp::VolumeProperties(doc.bodies[1].shape, props);
gp_Pnt com = props.CentreOfMass();
REQUIRE_THAT(double(com.X()), WithinAbs(5.0, 1e-4));
REQUIRE_THAT(double(com.Y()), WithinAbs(5.0, 1e-4));
}
TEST_CASE("fastened mate with flip", "[CadDocument][mate]")
{
using Catch::Matchers::WithinAbs;
CadDocument doc;
int sk = doc.add_sketch(SketchShape::Rectangle, SketchPlane::XY(), 10, 10, 0, "Box");
doc.add_extrude(sk, 5.0, false, BooleanMode::New, "E");
REQUIRE(doc.recompute());
REQUIRE(doc.error.empty());
int cs_fixed = doc.add_coordsys(CoordSysType::PointWorld, Vec3d(5, 5, 5), "CS_Fixed");
doc.features[cs_fixed].coordsys_body = 0;
REQUIRE(doc.recompute());
REQUIRE(doc.error.empty());
int sk2 = doc.add_sketch(SketchShape::Circle, SketchPlane::XY(), 0, 0, 3, "Cyl");
doc.add_extrude(sk2, 10.0, false, BooleanMode::New, "CylExt");
REQUIRE(doc.recompute());
REQUIRE(doc.error.empty());
int cs_moving = doc.add_coordsys(CoordSysType::PointWorld, Vec3d(0, 0, 5), "CS_Moving");
doc.features[cs_moving].coordsys_body = 1;
REQUIRE(doc.recompute());
REQUIRE(doc.error.empty());
doc.add_mate(0, cs_fixed, cs_moving, 0.0, 0.0, true, "Mate");
REQUIRE(doc.recompute());
REQUIRE(doc.error.empty());
GProp_GProps props;
BRepGProp::VolumeProperties(doc.bodies[1].shape, props);
gp_Pnt com = props.CentreOfMass();
REQUIRE_THAT(double(com.X()), WithinAbs(5.0, 1e-4));
REQUIRE_THAT(double(com.Y()), WithinAbs(5.0, 1e-4));
// Flip opposes Z axes: for a symmetric cylinder this is invisible in centroid,
// but the mate executed cleanly and the body moved to the target connector.
}
TEST_CASE("planar mate: normal distance becomes mate_offset", "[CadDocument][mate]")
{
using Catch::Matchers::WithinAbs;
CadDocument doc;
int sk = doc.add_sketch(SketchShape::Rectangle, SketchPlane::XY(), 10, 10, 0, "Box");
doc.add_extrude(sk, 5.0, false, BooleanMode::New, "E");
REQUIRE(doc.recompute());
REQUIRE(doc.error.empty());
int cs_fixed = doc.add_coordsys(CoordSysType::PointWorld, Vec3d(5, 5, 5), "CS_Fixed");
doc.features[cs_fixed].coordsys_body = 0;
REQUIRE(doc.recompute());
REQUIRE(doc.error.empty());
int sk2 = doc.add_sketch(SketchShape::Circle, SketchPlane::XY(), 0, 0, 3, "Cyl");
doc.add_extrude(sk2, 10.0, false, BooleanMode::New, "CylExt");
REQUIRE(doc.recompute());
REQUIRE(doc.error.empty());
int cs_moving = doc.add_coordsys(CoordSysType::PointWorld, Vec3d(20, 0, 0), "CS_Moving");
doc.features[cs_moving].coordsys_body = 1;
REQUIRE(doc.recompute());
REQUIRE(doc.error.empty());
doc.add_mate(1, cs_fixed, cs_moving, 3.0, 0.0, false, "MatePlanar");
REQUIRE(doc.recompute());
REQUIRE(doc.error.empty());
GProp_GProps props;
BRepGProp::VolumeProperties(doc.bodies[1].shape, props);
gp_Pnt com = props.CentreOfMass();
// Connector B was at z=0 (bottom of 10mm cylinder). After planar mate with
// offset=3 and A at z=5, the z-distance from A to B becomes 3 => B.z = 8.
// The cylinder centroid (was at z=5) moves to z=13.
REQUIRE_THAT(double(com.Z()), WithinAbs(13.0, 1e-4));
}
TEST_CASE("mate round-trip serialization", "[CadDocument][mate]")
{
using Catch::Matchers::WithinAbs;
CadDocument doc;
int sk = doc.add_sketch(SketchShape::Rectangle, SketchPlane::XY(), 10, 10, 0, "Box");
doc.add_extrude(sk, 5.0, false, BooleanMode::New, "E");
REQUIRE(doc.recompute());
REQUIRE(doc.error.empty());
int cs_a = doc.add_coordsys(CoordSysType::PointWorld, Vec3d(5, 5, 5), "CS_A");
doc.features[cs_a].coordsys_body = 0;
REQUIRE(doc.recompute());
REQUIRE(doc.error.empty());
int sk2 = doc.add_sketch(SketchShape::Circle, SketchPlane::XY(), 0, 0, 3, "Cyl");
doc.add_extrude(sk2, 10.0, false, BooleanMode::New, "CylExt");
REQUIRE(doc.recompute());
REQUIRE(doc.error.empty());
int cs_b = doc.add_coordsys(CoordSysType::PointWorld, Vec3d(20, 0, 5), "CS_B");
doc.features[cs_b].coordsys_body = 1;
REQUIRE(doc.recompute());
REQUIRE(doc.error.empty());
doc.add_mate(1, cs_a, cs_b, 7.25, 33.0, true, "Mate");
REQUIRE(doc.recompute());
REQUIRE(doc.error.empty());
size_t nb = doc.bodies.size();
auto blob = doc.serialize_recipe();
REQUIRE_FALSE(blob.empty());
CadDocument fresh;
REQUIRE(fresh.deserialize_recipe(blob));
REQUIRE(fresh.bodies.size() == nb);
const CadFeature* mf = nullptr;
for (const auto& f : fresh.features) {
if (f.type == CadFeatureType::Mate) { mf = &f; break; }
}
REQUIRE(mf != nullptr);
REQUIRE(mf->mate_kind == 1);
REQUIRE_THAT(mf->mate_offset, WithinAbs(7.25, 1e-9));
REQUIRE_THAT(mf->mate_angle, WithinAbs(33.0, 1e-9));
REQUIRE(mf->mate_flip == true);
}
TEST_CASE("version 2 blob is rejected", "[CadDocument][mate]")
{
using Catch::Matchers::Contains;
CadDocument doc;
int sk = doc.add_sketch(SketchShape::Rectangle, SketchPlane::XY(), 10, 10, 0, "Box");
doc.add_extrude(sk, 5.0, false, BooleanMode::New, "E");
REQUIRE(doc.recompute());
REQUIRE(doc.error.empty());
std::ostringstream oss;
{
cereal::BinaryOutputArchive ar(oss);
uint32_t fake_v = 2;
ar(fake_v);
ar(doc.features);
ar(doc.variables);
}
std::string blob = oss.str();
CadDocument fresh;
REQUIRE_FALSE(fresh.deserialize_recipe(blob));
REQUIRE_THAT(fresh.error, Catch::Matchers::Contains("older version"));
}
TEST_CASE("mate error: out of range connectors", "[CadDocument][mate]")
{
using Catch::Matchers::Contains;
CadDocument doc;
int sk = doc.add_sketch(SketchShape::Rectangle, SketchPlane::XY(), 10, 10, 0, "Box");
doc.add_extrude(sk, 5.0, false, BooleanMode::New, "E");
REQUIRE(doc.recompute());
REQUIRE(doc.error.empty());
int cs = doc.add_coordsys(CoordSysType::PointWorld, Vec3d(5, 5, 5), "CS");
doc.features[cs].coordsys_body = 0;
REQUIRE(doc.recompute());
REQUIRE(doc.error.empty());
doc.add_mate(0, 999, cs, 0, 0, false, "Bad");
REQUIRE_FALSE(doc.recompute());
REQUIRE_THAT(doc.error, Catch::Matchers::Contains("mate_cs_a out of range"));
doc.features.pop_back(); doc.error.clear();
doc.add_mate(0, cs, 999, 0, 0, false, "Bad");
REQUIRE_FALSE(doc.recompute());
REQUIRE_THAT(doc.error, Catch::Matchers::Contains("mate_cs_b out of range"));
doc.features.pop_back(); doc.error.clear();
doc.add_mate(0, sk, cs, 0, 0, false, "Bad");
REQUIRE_FALSE(doc.recompute());
REQUIRE_THAT(doc.error, Catch::Matchers::Contains("not a valid CoordSys"));
doc.features.pop_back(); doc.error.clear();
}
TEST_CASE("mate error: no associated body", "[CadDocument][mate]")
{
using Catch::Matchers::Contains;
CadDocument doc;
int sk = doc.add_sketch(SketchShape::Rectangle, SketchPlane::XY(), 10, 10, 0, "Box");
doc.add_extrude(sk, 5.0, false, BooleanMode::New, "E");
REQUIRE(doc.recompute());
REQUIRE(doc.error.empty());
int cs_fixed = doc.add_coordsys(CoordSysType::PointWorld, Vec3d(5, 5, 5), "CS_Fixed");
doc.features[cs_fixed].coordsys_body = 0;
REQUIRE(doc.recompute());
REQUIRE(doc.error.empty());
int cs_moving = doc.add_coordsys(CoordSysType::PointWorld, Vec3d(0, 0, 5), "CS_Moving");
REQUIRE(doc.recompute());
REQUIRE(doc.error.empty());
doc.add_mate(0, cs_fixed, cs_moving, 0, 0, false, "Bad");
REQUIRE_FALSE(doc.recompute());
REQUIRE_THAT(doc.error, Catch::Matchers::Contains("no associated body"));
}
TEST_CASE("mate error: disabled connector", "[CadDocument][mate]")
{
using Catch::Matchers::Contains;
CadDocument doc;
int sk = doc.add_sketch(SketchShape::Rectangle, SketchPlane::XY(), 10, 10, 0, "Box");
doc.add_extrude(sk, 5.0, false, BooleanMode::New, "E");
REQUIRE(doc.recompute());
REQUIRE(doc.error.empty());
int cs_fixed = doc.add_coordsys(CoordSysType::PointWorld, Vec3d(5, 5, 5), "CS_Fixed");
doc.features[cs_fixed].coordsys_body = 0;
int cs_moving = doc.add_coordsys(CoordSysType::PointWorld, Vec3d(0, 0, 5), "CS_Moving");
doc.features[cs_moving].coordsys_body = 0;
REQUIRE(doc.recompute());
REQUIRE(doc.error.empty());
doc.features[cs_moving].enabled = false;
doc.add_mate(0, cs_fixed, cs_moving, 0, 0, false, "Bad");
REQUIRE_FALSE(doc.recompute());
REQUIRE_THAT(doc.error, Catch::Matchers::Contains("not a valid CoordSys"));
}
TEST_CASE("ordering: fillet after mate resolves face ids", "[CadDocument][mate]")
{
using Catch::Matchers::WithinAbs;
CadDocument doc;
int sk_a = doc.add_sketch(SketchShape::Rectangle, SketchPlane::XY(), 10, 10, 0, "BoxA");
doc.add_extrude(sk_a, 5.0, false, BooleanMode::New, "EA");
REQUIRE(doc.recompute());
REQUIRE(doc.error.empty());
int sk_b = doc.add_sketch(SketchShape::Rectangle, SketchPlane::XY(), 10, 10, 0, "BoxB");
doc.add_extrude(sk_b, 5.0, false, BooleanMode::New, "EB");
REQUIRE(doc.recompute());
REQUIRE(doc.error.empty());
REQUIRE(doc.bodies.size() == 2);
int cs_fixed = doc.add_coordsys(CoordSysType::PointWorld, Vec3d(5, 5, 5), "CS_Fixed");
doc.features[cs_fixed].coordsys_body = 0;
REQUIRE(doc.recompute());
REQUIRE(doc.error.empty());
int cs_moving = doc.add_coordsys(CoordSysType::PointWorld, Vec3d(5, 5, 5), "CS_Moving");
doc.features[cs_moving].coordsys_body = 1;
REQUIRE(doc.recompute());
REQUIRE(doc.error.empty());
doc.add_mate(0, cs_fixed, cs_moving, 0.0, 0.0, false, "Mate");
REQUIRE(doc.recompute());
REQUIRE(doc.error.empty());
doc.add_fillet(1.0, FaceGroup::All, "FilletAfterMate");
doc.features.back().target_body = 1;
REQUIRE(doc.recompute());
REQUIRE(doc.error.empty());
}
// --- M8a fix round: planar antiparallel + blind tests ---
static int find_face_by_normal(const CadDocument& doc, int body_idx, const Vec3d& dir, double tol = 0.99)
{
auto faces = GeometryEngine::faces_of(doc.bodies[body_idx].shape);
for (int fi = 0; fi < int(faces.size()); ++fi) {
if (GeometryEngine::face_normal_world(faces[fi]).dot(dir) > tol) return fi;
}
return -1;
}
TEST_CASE("planar mate: antiparallel normals with asymmetric body", "[CadDocument][mate]")
{
using Catch::Matchers::WithinAbs;
CadDocument doc;
// Body A: box 20x20x5, centered at origin in XY
int sk_a = doc.add_sketch(SketchShape::Rectangle, SketchPlane::XY(), 20, 20, 0, "BoxA");
doc.add_extrude(sk_a, 5.0, false, BooleanMode::New, "EA");
REQUIRE(doc.recompute());
REQUIRE(doc.error.empty());
// Body B: box 20x10x5, also centered at origin (asymmetric in Y)
int sk_b = doc.add_sketch(SketchShape::Rectangle, SketchPlane::XY(), 20, 10, 0, "BoxB");
doc.add_extrude(sk_b, 5.0, false, BooleanMode::New, "EB");
REQUIRE(doc.recompute());
REQUIRE(doc.error.empty());
REQUIRE(doc.bodies.size() == 2);
// Face on A with normal +X, face on B with normal -X
int faceA = find_face_by_normal(doc, 0, Vec3d(1, 0, 0));
REQUIRE(faceA >= 0);
int faceB = find_face_by_normal(doc, 1, Vec3d(-1, 0, 0));
REQUIRE(faceB >= 0);
// Verify z_A != z_B (they point opposite)
Vec3d nA_pre = GeometryEngine::face_normal_world(
GeometryEngine::face_by_index(doc.bodies[0].shape, faceA));
Vec3d nB_pre = GeometryEngine::face_normal_world(
GeometryEngine::face_by_index(doc.bodies[1].shape, faceB));
REQUIRE(nA_pre.dot(nB_pre) < -0.9); // antiparallel
int cs_fixed = doc.add_coordsys(CoordSysType::FaceAndDirection, Vec3d(0,0,0), "CS_Fixed");
doc.features[cs_fixed].coordsys_body = 0;
doc.features[cs_fixed].coordsys_face = faceA;
REQUIRE(doc.recompute());
REQUIRE(doc.error.empty());
int cs_moving = doc.add_coordsys(CoordSysType::FaceAndDirection, Vec3d(0,0,0), "CS_Moving");
doc.features[cs_moving].coordsys_body = 1;
doc.features[cs_moving].coordsys_face = faceB;
REQUIRE(doc.recompute());
REQUIRE(doc.error.empty());
// Planar mate: z_A=+X, z_B=-X antiparallel. offset=0.
// With fix: 180° flip, then translated so z-distance=0.
// Without fix: no rotation, only translation — body X-centroid moves differently.
doc.add_mate(1, cs_fixed, cs_moving, 0.0, 0.0, false, "PlanarAnti");
REQUIRE(doc.recompute());
REQUIRE(doc.error.empty());
// With the fix: 180° rotation about faceB centroid, then translation.
// Body B's X-extents are mirrored. After rotation, centroid X = 2*o_B.x - pre_cx = -20,
// then translated by offset ≈ 20mm → centroid returns near 0.
// Without the fix: no rotation, body just translates ~+20mm → centroid X ≈ 20.
GProp_GProps post_props;
BRepGProp::VolumeProperties(doc.bodies[1].shape, post_props);
double post_cx = post_props.CentreOfMass().X();
REQUIRE_THAT(std::abs(post_cx), WithinAbs(0.0, 1e-4));
}
TEST_CASE("planar mate: in-plane pose preserved", "[CadDocument][mate]")
{
using Catch::Matchers::WithinAbs;
CadDocument doc;
int sk_a = doc.add_sketch(SketchShape::Rectangle, SketchPlane::XY(), 20, 20, 0, "BoxA");
doc.add_extrude(sk_a, 5.0, false, BooleanMode::New, "EA");
REQUIRE(doc.recompute());
REQUIRE(doc.error.empty());
int sk_b = doc.add_sketch(SketchShape::Rectangle, SketchPlane::XY(), 10, 10, 0, "BoxB");
doc.add_extrude(sk_b, 10.0, false, BooleanMode::New, "EB");
REQUIRE(doc.recompute());
REQUIRE(doc.error.empty());
REQUIRE(doc.bodies.size() == 2);
GProp_GProps pre_props;
BRepGProp::VolumeProperties(doc.bodies[1].shape, pre_props);
gp_Pnt pre_com = pre_props.CentreOfMass();
// Both connectors use PointWorld (z=(0,0,1)). B's connector offset in X/Y from A's.
int cs_fixed = doc.add_coordsys(CoordSysType::PointWorld, Vec3d(10, 10, 5), "CS_Fixed");
doc.features[cs_fixed].coordsys_body = 0;
int cs_moving = doc.add_coordsys(CoordSysType::PointWorld, Vec3d(7, 4, 10), "CS_Moving");
doc.features[cs_moving].coordsys_body = 1;
REQUIRE(doc.recompute());
REQUIRE(doc.error.empty());
doc.add_mate(1, cs_fixed, cs_moving, 0.0, 0.0, false, "PlanarSameZ");
REQUIRE(doc.recompute());
REQUIRE(doc.error.empty());
GProp_GProps post_props;
BRepGProp::VolumeProperties(doc.bodies[1].shape, post_props);
gp_Pnt post_com = post_props.CentreOfMass();
// In-plane (X,Y) components unchanged, only Z moves.
REQUIRE_THAT(double(post_com.X()), WithinAbs(double(pre_com.X()), 1e-4));
REQUIRE_THAT(double(post_com.Y()), WithinAbs(double(pre_com.Y()), 1e-4));
REQUIRE_THAT(double(post_com.Z()), !WithinAbs(double(pre_com.Z()), 1e-4));
}
TEST_CASE("mate with FaceAndDirection connectors on non-Z faces", "[CadDocument][mate]")
{
using Catch::Matchers::WithinAbs;
CadDocument doc;
// Body A: box 20x20x10
int sk_a = doc.add_sketch(SketchShape::Rectangle, SketchPlane::XY(), 20, 20, 0, "BoxA");
doc.add_extrude(sk_a, 10.0, false, BooleanMode::New, "EA");
REQUIRE(doc.recompute());
REQUIRE(doc.error.empty());
// Face on A with normal +Y
int faceA = find_face_by_normal(doc, 0, Vec3d(0, 1, 0));
REQUIRE(faceA >= 0);
int cs_fixed = doc.add_coordsys(CoordSysType::FaceAndDirection, Vec3d(0,0,0), "CS_Fixed");
doc.features[cs_fixed].coordsys_body = 0;
doc.features[cs_fixed].coordsys_face = faceA;
REQUIRE(doc.recompute());
REQUIRE(doc.error.empty());
// Body B: box placed at a different location
int sk_b = doc.add_sketch(SketchShape::Rectangle, SketchPlane::XY(), 10, 10, 0, "BoxB");
doc.add_extrude(sk_b, 5.0, false, BooleanMode::New, "EB");
REQUIRE(doc.recompute());
REQUIRE(doc.error.empty());
// Face on B with normal +Y
int faceB = find_face_by_normal(doc, 1, Vec3d(0, 1, 0));
REQUIRE(faceB >= 0);
int cs_moving = doc.add_coordsys(CoordSysType::FaceAndDirection, Vec3d(0,0,0), "CS_Moving");
doc.features[cs_moving].coordsys_body = 1;
doc.features[cs_moving].coordsys_face = faceB;
REQUIRE(doc.recompute());
REQUIRE(doc.error.empty());
// Fastened mate: B's +Y face lands on A's +Y face, offset=0.
// Both normals are +Y so z_A = z_B = (0,1,0) — genuine rotation from frame composition.
doc.add_mate(0, cs_fixed, cs_moving, 0.0, 0.0, false, "MateY");
REQUIRE(doc.recompute());
REQUIRE(doc.error.empty());
// After fastened mate, the two mated faces should be coincident:
// same centroid position along the normal (Y), and same centroid in X and Z
// (within face dimensions since they're different sizes).
Vec3d ca = GeometryEngine::face_centroid_world(GeometryEngine::face_by_index(doc.bodies[0].shape, faceA));
Vec3d cb = GeometryEngine::face_centroid_world(GeometryEngine::face_by_index(doc.bodies[1].shape, faceB));
REQUIRE_THAT(cb.x(), WithinAbs(ca.x(), 1e-4));
REQUIRE_THAT(cb.y(), WithinAbs(ca.y(), 1e-4));
REQUIRE_THAT(cb.z(), WithinAbs(ca.z(), 1e-4));
}
TEST_CASE("fastened mate with flip on asymmetric body", "[CadDocument][mate]")
{
using Catch::Matchers::WithinAbs;
CadDocument doc;
// Body A: box
int sk_a = doc.add_sketch(SketchShape::Rectangle, SketchPlane::XY(), 20, 20, 0, "BoxA");
doc.add_extrude(sk_a, 10.0, false, BooleanMode::New, "EA");
REQUIRE(doc.recompute());
REQUIRE(doc.error.empty());
// Body B: tapered extrude (asymmetric, centroid not at geometric centre)
int sk_b = doc.add_sketch(SketchShape::Rectangle, SketchPlane::XY(), 10, 10, 0, "BoxB");
int ex_b = doc.add_extrude(sk_b, 8.0, false, BooleanMode::New, "EB");
doc.features[ex_b].taper_deg = 8.0;
REQUIRE(doc.recompute());
REQUIRE(doc.error.empty());
// PointWorld connectors at distinct positions.
// A's connector on the top face centre, B's connector at a corner.
int cs_fixed = doc.add_coordsys(CoordSysType::PointWorld, Vec3d(10, 10, 10), "CS_Fixed");
doc.features[cs_fixed].coordsys_body = 0;
int cs_moving = doc.add_coordsys(CoordSysType::PointWorld, Vec3d(2, 3, 0), "CS_Moving");
doc.features[cs_moving].coordsys_body = 1;
REQUIRE(doc.recompute());
REQUIRE(doc.error.empty());
// Fastened, NO flip
doc.add_mate(0, cs_fixed, cs_moving, 0.0, 0.0, false, "MateNoFlip");
REQUIRE(doc.recompute());
REQUIRE(doc.error.empty());
GProp_GProps nf_props;
BRepGProp::VolumeProperties(doc.bodies[1].shape, nf_props);
double nf_z = nf_props.CentreOfMass().Z();
doc.undo();
// Fastened, WITH flip
doc.add_mate(0, cs_fixed, cs_moving, 0.0, 0.0, true, "MateFlip");
REQUIRE(doc.recompute());
REQUIRE(doc.error.empty());
GProp_GProps f_props;
BRepGProp::VolumeProperties(doc.bodies[1].shape, f_props);
double f_z = f_props.CentreOfMass().Z();
// Flip changes the centroid Z for an asymmetric body
REQUIRE_THAT(f_z, !WithinAbs(nf_z, 1e-4));
}