slice_single_volume_regions() sliced Precise Seam modifiers with
trafo_centered(), but a belt printer slices its layers with
trafo_sliced(): the belt rotation, any pre-slice remap and the lift off
the plate on top. On a belt print the modifier regions landed in the
unrotated frame, away from the walls they were meant to place the seam
on. Slice them with trafo_sliced(), as the support volumes and the seam
enforcers already are. It equals trafo_centered() off a belt printer.
Brings belt-printer up to main 4b4a261787. Resolutions:
- G-code header (#15897, #15915): main moved the header, config and
thumbnail block later in _do_export; write_belt_header() moves with it,
still after the thumbnails and outside the BTT_TFT gate.
- _extrude: first-layer acceleration keeps the per-path first-layer plane
test with main's cached nozzle index (#16028); main's set_speed out-param
form (#16108) everywhere else.
- GCodeWriter (#16108): the arc-to-polyline fallback for machine mappings
that cannot express G2/G3 now runs in the out-param extrude_arc_to_xy,
which is the overload GCode calls, and appends to the caller's string.
- GCodeProcessorResult: the belt fields join main's forwarding assign.
- Clipper2 (#15969): belt arrange helpers take Slic3r::Point; the tree
support join types lose their ClipperLib qualifier.
- CLI arrange (#15837): belt printers still reserve no wipe tower.
- Wipe tower options (#15841): the two new sparse-layer toggles are hidden
for belt printers like the rest of the tower options.
- Keyboard shortcuts (#15706): main's registry replaces the old key switch;
the belt view toggle is re-registered in the next commit.
- Print::process: the belt purge-plan undo runs before main's SliceStarted
event.
- scripts/filament_id_snapshot.json: deleted on main (a77209af8f).
- Includes and appended tests: union of both sides.
perf: skip estimating curled walls when nothing reads them
The curled extrusion estimate ran whenever a region had overhang speed on,
which is the default, but only the slowdown for curled perimeters reads the
curled lines it produces, and that slowdown is off by default. The step now
also requires a region with the slowdown on, and clears the curled lines
when it skips the estimate, so none are left from an earlier slice.
Also fixes stale fan commands due to the stale curled lines on the reused layers.
Every file that included STEP.hpp, directly or not, got namespace fs = boost::filesystem at global scope, and 29 sources and three headers relied on it without saying so. Headers now spell out boost::filesystem, and each source that uses fs declares the alias itself.
* Fix CLI Crashes on Malformed Project, Assemble List and No-Input Runs
Four CLI paths indexed vectors without checking their size and crashed
with SIGSEGV on malformed input:
- A project inherits_group whose length is not the filament count plus
the process and printer entries was split by position. It is now
ignored with a warning, as if the project had none.
- An assemble list object with an empty filaments list passed validation
and was then read at index 0. It is now rejected as a config error, as
is a negative filament id.
- --slice N --arrange 1 on a project without plate metadata read the
missing plate data. It now falls back to the plate's own filaments,
like the other plate data reads.
- --assemble with no input model built an object with no volumes. It is
now rejected as invalid parameters.
A tests/cli script covers each case through the binary, since all four
live inline in CLI::run().
* Move the Assemble List Parser into libslic3r
Behaviour-preserving move of the --load-assemble-list JSON parser and
its plate/object structs from the CLI into libslic3r/Format/AssembleList,
so the format can be unit tested. The parser returns its own
AssembleListResult and takes the plate limit as a parameter; CLI::run
maps the result to the same exit codes as before. Every validation rule
and log message is unchanged.
Adds Catch2 coverage of the valid layout and each validation rule.
* Keep the Process and Printer of an inherits_group of the Wrong Length
A project whose inherits_group did not have one entry per filament plus
the process and printer entries was loaded as if it had none. The CLI
then looked for system presets under the names of the user presets,
found none and refused to slice a project that slices on main.
The group is now read as before: the process first, the printer last
and the filaments in between, up to the filament count. A filament
without an entry counts as a system preset. A group with fewer than two
entries is still ignored. The warning stays.
The purge plan snaps every object onto one layer grid after the brim is built;
the per-layer brim bands follow their layers but the apron bands below the
first layer carry their own print_z and were left behind, which is why a brim
was refused next to a purge tower object. The shift now moves them too and the
combination is accepted again.
On a belt the parts print in belt order, so every colour change between parts
is a filament change. Arrange packs items in extruder order already, but it
grew the pile around its centre, so the colours ended up interleaved. A belt
print now packs from the leading end of the bed, each row filling across the
belt before the pile advances, and the objective charges an item for every
packed part of another colour it does not fully follow along the belt,
counting the tilted layers that reach cot(angle) * height past a part, so
each colour prints as one run. The direction follows the slicing rotation: a
rotation about X prints toward +Y, one about Y toward -X, and a negative angle
flips it. Packing from the edge also means the brim has to be kept on the
bed: a belt brim is printed brim_width wide for every brim type, so that much
is reserved along every edge (between parts the brims may overlap, as on any
printer).
The purge prism is regenerated from the arranged parts, flush with the far
edge of the bed, yet arrange moved it about like a part and packed parts into
the strip it comes back to. Arrange now skips the prism and reserves its strip
with a fixed virtual item, like a bed exclusion area, whenever the parts use
more than one filament.
The prism's length follows the parts plus a ramp per unit of height; with the
height at its cap that ran 100 mm past the end of a 500 mm belt and the project
could not print. The bar now stops at the plate end, and the purge planner's
existing warning reports what the shortened bar cannot absorb.
Release builds install each vendor as its preset cache alone. The
read-only preset load the CLI uses to resolve an inheriting user preset
passed allow_cache = false to keep caches from being written, which
also stopped them from being read, so every vendor fell back to JSONs
that are not installed and the CLI failed.
The flag now only gates writing: a read-only load reads caches and
writes none. The filament library is also read from its cache whenever
that is all that is installed, so a vendor updated over the air still
resolves against it.
* Refresh a CLI Project's Filament Settings From Their System Presets
The CLI loads a project's printer and process settings as the GUI does,
taking every key the project does not list as changed from the current
system preset, but it kept the stored filament values. A project saved
before a profile update then sliced with old filament values on the
command line and with the current ones in the GUI.
Every project filament that no loaded filament replaces is now resolved
by its system preset name and fed to the filament merge the up-to-date
path already uses, which keeps the keys listed in
different_settings_to_system and maps per-variant values onto the
preset's variants. This covers a plain run, --uptodate without
--uptodate-filaments, and the slots --load-filaments leaves empty. The
merge tells refreshed entries from loaded ones per entry instead of by
the global loaded-filament count, and the entries are kept in slot
order. A project filament saved under a name the presets have since
split per nozzle is resolved through the name conversion the GUI uses,
which PresetBundle now exposes.
* Check the Project Refresh Test's Result Directly
Shellcheck SC2181: test the checker's exit status in the if instead of
reading $? afterwards.
* Ignore Clipper, libpng, mcut and Boost.Polygon Internals in clang-tidy
Each only works through a wrapper or umbrella header: libslic3r/clipper.hpp or clipper_z.hpp configure Clipper before including it, png.h pulls in libpng's config headers, and Boost.Polygon's headers only compile through polygon.hpp or voronoi.hpp.
* Ignore minilzo's Config Headers in clang-tidy
lzoconf.h and lzodefs.h are internal to minilzo.h, which is what the code includes.
* Add Missing Includes Across the Remaining Sources and Tests
Covers src/slic3r/Utils, src/slic3r/plugin, src/slic3r/Config, src/libvgcode, src/dev-utils, src/OrcaSlicer.cpp and tests/, the directories left after src/slic3r/GUI and src/libslic3r. Generated with clang-tidy misc-include-cleaner. libvgcode's own headers are included by relative path as in the rest of that library, and Catch2 and pybind11 with angle brackets as elsewhere in the repo.
* Make the GUI and Test Headers Compile on Their Own
Each now includes, or forward-declares, what it uses instead of relying on what its includers happened to include first. Headers that only compile on one platform, or that nothing built includes, are left alone.
* Keep Windows and nanosvg Setup Ahead of the Added Includes
OrcaSlicer.cpp and several tests set _WIN32_WINNT, WIN32_LEAN_AND_MEAN or NOMINMAX before including Windows.h, and the profile validator defines NANOSVG_IMPLEMENTATION before any libslic3r header. The added includes had landed above those blocks, which broke the Windows build.
* Add the GUI Includes the First Pass Missed
Covers headers that only became editable once they compiled on their own, and wx symbols whose suggested header changed as the clang-tidy ignore list grew after the src/slic3r/GUI pass.
* Keep the Added Test Includes Below the NOMINMAX Guard
test_marchingsquares.cpp and test_texture_displacement.cpp had includes inside #ifndef NOMINMAX, which the tests inherit as defined on Windows from libslic3r, so those were skipped there. .clang-tidy also ignores the MSVC STL and UCRT internals, Boost.Multiprecision's fwd.hpp and CPython's Windows include directory, as in #16068.
The band was a second pass over the finished layer that fought the fan commands
the layer pass had already written (overhang, bridge and resume requests). The
generator now marks where each segment enters and leaves the band and the layer
pass treats the band as the strongest fan request, so there is one place that
decides the fan.
The purge plan moves objects onto a common layer grid after the brim bands are
built, so the two cannot share a print. The prime tower setting alone still does
not block a brim. The missing-prism warning now counts the filaments the objects
use, as the GUI does.
With best_object_pos away from the bed centre the placer packs the pile
inside the bin and then translates it so its centre lands on that point,
without checking that it still fits there. A belt printer aims at the
leading end of the belt (BabyBelt Pro: 0.5, 0.05), so any pile longer than
the 50 mm around that point was pushed past the edge: four 90 mm parts on
the 95 x 500 mm belt ended with one across the edge and one outside while
290 mm of belt stayed free.
The final alignment now stops the pile at the edge of the bin; the items'
inflated boxes leave the object spacing as the margin. A pile that does not
fit along an axis is centred on it, as before.
* Keep User Preset Values on Extruder Variants They Don't List
A user preset stores the variant list its parent had when it was saved.
When the parent later gains variants, update_diff_values_to_child_config
matched variants by name only and left the new ones at the parent's
value, so the user's settings were silently replaced there, and a
re-save wrote the system values into the user's file.
An unmatched parent variant now takes the child's first variant of the
same extruder, the rule slicing already uses in get_config_index_base.
A child without a variant list covers the parent's first extruder. The
name match also no longer indexes the child's extruder ids when it has
none.
* Share One Variant Column Rule Between Slicing, User Presets and Projects
Three places chose which variant column a value comes from, each with
its own copy of "the same variant and owner, else the owner's first
column": get_config_index_base when slicing, the user preset merge in
update_diff_values_to_child_config, and normalize_filament_values_to_variants
for projects and the CLI.
find_variant_column now holds that rule and map_variant_columns applies
it to a variant list, so a change to how missing variants are filled
reaches all three. Each caller keeps its own copy step. There is no
behaviour change: G-code is identical before and after. The one
relaxation is that get_config_index_base no longer reads past a short
id list when its two lists differ in length, which its assert already
rules out.
* Rename variant column helpers to variant index
---------
Co-authored-by: SoftFever <softfeverever@gmail.com>
* Make Painted Multi-Material Slicing Deterministic
Painted (multi-material) models sliced to slightly different G-code on
every run: ±1 µm wall coordinates and reordered islands. Hashing each stage
of the segmentation across runs showed the projected painted lines and the
per-layer Voronoi segmentation were stable; the raw top/bottom projections
from slice_mesh_slabs() were not. Three causes, all thread-order dependent:
- slice_slabs_make_lines() appends each slab's intersection lines from a
parallel facet loop and never restored a canonical order, so the loop
start vertices and polygon order from make_slab_loops() depended on
scheduling. Sort every slab's lines with the same key slice_make_lines()
already uses.
- segmentation_top_and_bottom_layers() wrote a layer's shell projections
into neighbouring layers' vectors from the parallel loop, relying on a
parity double-buffer that assumes TBB ranges are exactly one group wide
and aligned, which blocked_range does not guarantee; two threads could
append to the same vector. Each source layer now records its projections
in its own slot and they are gathered per target layer in source order.
- The painted-line sort in post_process_painted_lines() was not a total
order: projections of one span from facets of different colours tied on
every key and the first one won the span. Colour and end points now break
the tie.
Three multi-threaded runs of each painted fixture now give one G-code;
unpainted output is unchanged.
* Test That Slab Slicing Does Not Depend on the Thread Schedule
Projects a dense, tilted sphere with slice_mesh_slabs() on one thread and
then three times multi-threaded, and requires the polygons to match exactly,
vertex order included. Fails without the canonical line sort, passes with it.
The clearance test needs the relative-E reset in its layer change G-code to
get past validate()'s other checks, and now asserts the height message. The
fan band test counts cycles rather than commands: the band is decided per
path start, so a cube cycles the fan far less often than a benchy.
Covers the case from Hanif Koh's review of #14394 (belt raft layers below
the object with no lower bound), which the negative-Z bottom layer fix in
layer_initialize() addresses.
With a first layer of about 0.28 mm or more at 45 degrees (or a shallower
belt) the brim band is wider than one bead and its lines go on the nominal
lattice. A lattice line could land where the belt is almost at the band's
print_z; its flow was clamped to half a layer while the nozzle sat nearly on
the belt. Such a line now moves uphill to the 0.75 fraction the single-line
case uses, and a line that lands on the previous one is skipped.
Ported from the Unlayered fork (patch 0007 of its belt port series, found
there by fuzzing first layer heights). The fork's companion fix, restricting
the brim filament to those the writer was handed (0008), is not needed here:
ToolOrdering registers the brim filament on every band's layer, so the writer
always has it. A test pins that with every object a flush target.
The purge tower is a model object the GUI creates and sizes, and libslic3r
only purges into one that exists. A multi-filament belt project sliced from
the CLI without it changed filament with nowhere to purge, silently.
Raised in Hanif Koh's review of #14394.
The cooling buffer's band pass rebuilt positions from the layer's G-code
and tested them against the first-layer plane. The G-code is in machine
coordinates and the plane is in slicing coordinates, so on the shipped
profiles the nearest move was over 100 mm from a 0.2 mm band and the pass
never changed the fan. GCode::_extrude() already knows each path's height
above the belt, so it now tags the band changes and the buffer applies and
strips the tags.
The pass also took the S of every M106 as the part fan, whatever its P
index, and stored that 0..255 value where a percentage was expected (an
auxiliary fan line came back as M106 S651); it now uses FanMover's parser,
which ignores other fans, and converts to percent. It no longer overwrites
the layer's intended speed, only the fan's actual state.
Raised in Hanif Koh's review of #14394.
enable_prime_tower stays on for any multi-filament project, but a belt
printer never prints the classic tower and the belt purge prism is an
ordinary object that never takes a brim, so every brim on a multi-filament
belt print was refused for nothing.
Raised in Hanif Koh's review of #14394.
validate() skipped the build-volume height check whenever the machine-frame
transform was active, which is every shipped belt profile, so a 400 mm
object passed on a 300 mm printable_height. The transform only changes how
the height is written to G-code; the clearance check from f682ab5cd3
applies regardless.
Raised in Hanif Koh's review of #14394.
* Lock Config and Preset Files Across Instances and Write Them Atomically
Every running instance shares one OrcaSlicer.conf and one user preset
tree, and nothing kept their writers apart. Two instances saving at the
same moment, or the cloud preset sync thread writing while the GUI thread
saved, could interleave, and a reader in another instance could open a
preset JSON or .info file between truncate and close and get a partial
file, dropping that preset for the session with a parse error.
Add InstanceLock, a scoped guard that serialises the threads of one
process through a recursive mutex and other processes through an advisory
OS file lock: flock on POSIX, held on the guard's own descriptor so no
other close in the process can drop it, and LockFileEx on Windows. The
outermost guard opens the lock file and closes it on release, so nothing
stays open between saves and a data dir can be removed once nothing is
saving into it; the file itself is kept, since deleting it would let a
third instance lock a fresh file while the second still holds the old
one. It is best effort: when the lock file cannot be opened or locked, or
another instance still holds it after a second, the guard logs once and
lets the write proceed, then leaves the file alone for ten seconds, so a
hung instance never blocks every other one and a holder stuck in a
debugger does not cost a stall per save. The guard sits at the leaf
readers and writers: set_sync_info_and_save() calls save_info() under the
preset collection mutex, so a batch lock around save_user_presets() would
invert the order against the sync thread. The user preset scan reads its
files on worker threads without the guard, since the mutex would
serialise them, and takes it per file in the serial commit step, so a
save never waits for the whole scan. Each read keeps the bytes of the
preset and its .info as they were before parsing; commit compares them
with the disk under the guard and reads a file that changed again, so it
never deletes or writes back over another instance's newer save, nor
installs a .json and .info from two different saves; a preset another
instance removed in the meantime is not installed. Without the guard, in
a cool-down, the scan still loads the presets but leaves their files
alone: an unreadable file stays for the next scan, and a derived
compatible printer is not written back. Read-only scans, which is what
the CLI does, take no lock and create no lock file.
AppConfig holds OrcaSlicer.conf.lock in load() and save(); load is
included because the Windows path restores from the .bak copy. Every
user preset writer and reader holds user.lock: Preset::save(), which
writes no .info when the preset itself could not be written, since an
.info without its preset reads as a cloud deletion request, save_info(),
reload() and remove_files(), each preset the scan commits, the
bundle metadata reads and write, the .info removal after a cloud-confirmed
delete, the orphaned-.info scan on the sync thread, the bundle folder
removal on unsubscribe and the physical printer writers and delete
paths. A bundle import extracts under cache/ into a folder per process
and per import, where no scan reads.
Preset JSON, .info, bundle metadata, physical printer and config files,
and the caches and state files that already used a temporary by hand,
now go through write_file_atomically(), which writes <file>.<pid>.<n>.tmp
beside the target and renames it over, so a reader that never waits sees
a complete old or new file. A symlink is followed; a target that is not
a regular file is written in place; and when no temporary can be created
beside an existing target, or the rename itself is refused, by a Windows
reader holding the file open or a mount that cannot replace in one step,
the helper writes in place as before, since losing the save is worse
than a torn read. On POSIX the rename replaces the
target atomically where the old code removed it first and left a window
with no file at all; only a mount that refuses a one-step replace gets
the old remove-then-rename. A crash between temporary and rename leaves
the temporary behind, which no scan reads. Preset::save() returns
whether it wrote the preset, so the scan counts a compatible printer it
could not write back as an error. A failed config write keeps
the config dirty, and the idle handler waits ten seconds before retrying
while an explicit save always tries.
* Run the Cross-Process Lock Test on Every Platform
The test that checks the guard yields to a lock held elsewhere forked a
child to hold it, so it was left out on Windows. The OS lock belongs to
the handle on Windows and to the open file description elsewhere, so a
second handle in the same process is refused like another instance
would be. The test now holds the lock that way and runs everywhere.
extrude_infill() and extrude_support() reversed the layer's extrusion
entities in place while chaining them, so each export started from the
previous one's reversed toolpaths, and each copy of an object from the
copy before it. The export-time region lists now hold const pointers,
and chaining reverses a clone instead.
The display-name tests call set_user_session(), which persists the session.
The agent they built was in keychain mode, so every run saved a fake
OrcaSlicer/Auth session into the system keychain of whoever ran the tests,
replacing their real Orca Cloud login on any desktop with a working keychain.
Move them next to the other agent tests and build the agent the same way:
encrypted-file mode with a throwaway config directory.
An ironing line spacing of 0 reached the fillers from a 3MF, the CLI or
the per-filament override, which has no GUI guard. Concentric ironing
then never finished slicing, because a zero inset never shrinks the
region, and rectilinear ironing was silently dropped. Tiny positive
values produced an unprintable number of lines.
Top surface and support ironing now clamp the spacing to the 0.05 mm
floor the process GUI guard already enforces, so these configurations
iron at that spacing. Spacings at or above the floor, including every
shipped profile, are unchanged. The concentric filler also returns early
on a non-positive step so no other caller can hang it, and the filament
settings page now resets a too-small override the same way the process
page does.
The plugin test fixtures start the interpreter before the test points
data_dir at its temporary directory, so PythonInterpreter creates
{data_dir}/python/packages and {data_dir}/log with an empty data_dir: a
python/ and log/ folder in whatever directory the tests run from. When that
is the test binary's folder, the next run's embedded-interpreter tests took
the stray python/ as their home and failed to start Python.
Give each fixture that initializes the plugin manager its own temporary
data directory, set up before initialize(), and only use the python/ folder
next to the test binary as the interpreter's home when it holds a standard
library.
With stealth mode off the home page asks for the login status every 2 s,
and while nobody is logged in that ends in clear_user_secret(), which
opened the system keychain and deleted the OrcaSlicer/Auth entry on the
UI thread every tick. A working keychain cost a D-Bus round trip per tick;
a keychain that never answers blocked the UI for 25 s per tick. It also
deleted a login another running instance had just saved, and ignored
use_encrypted_token_file, so opting out of the keychain did not help.
Remember whether this process read a secret from the store or wrote one,
and only then touch the store when a logged-out poll asks for a logout.
A logged-out instance never touches the keychain, and in encrypted-file
mode the poll no longer opens the keychain at all. A secret this process
cannot read, such as a token file encrypted for another OS user sharing
the data directory, is left alone by the poll. An explicit logout still
wipes both backends, so a token stranded by switching the token storage
option cannot sign the account back in later.
# Description
Include variant-aware validation, temperature and pressure controls,
named nozzle selection, and filament sidebar refresh.
## Support nozzle-specific filament cooling and tuning
Filament presets can require different cooling and tuning for Standard
and High Flow nozzle variants. This change makes part and auxiliary
cooling, pressure advance, temperature limits, and multitool ramming
settings follow the selected variant, with matching UI controls and
profile validation.
The Snapmaker U1 profiles in #15755 / Snorca illustrate why this
matters:
| Profile | Standard cooling | High Flow cooling |
|---|---|---|
| Snapmaker ABS | Part fan: 15–15% | Part fan: 10–60% |
| Snapmaker PETG HF, 0.4 mm | Part fan: 20–40% | Part fan: 30–60% |
| Snapmaker PETG-CF | Part fan: 0–20%; auxiliary: 0% | Part fan: 5–40%;
auxiliary: 20% |
| Snapmaker PLA Matte | Auxiliary: 80% | Auxiliary: 100% |
These differences need to survive variant selection, editing, and
slicing. Shared single values continue to apply across variants, and
short filament arrays fall back to element zero, matching the loader.
### Additional changes
- Preserve named nozzle selections when refreshing the diameter
selector.
- Enable or disable the pressure-advance input for the selected variant.
- Initialize profile-validation slicing with the printer’s declared
nozzle volume type.
- Refresh filament controls after preset loading.
Profile changes remain separate in `u1-hf`.
### Validation
- All 13 focused variant-tool tests passed.
- Broader checks encountered an existing Windows path-separator
assertion failure, reproduced with upstream code.
- C++ build and GUI validation have not been run.
[How to Download Pull Requests Artifacts for
Testing](https://www.orcaslicer.com/wiki/how_to_download_pr_artifacts)
## Summary
Adds a new paint-style **Texture Displacement** gizmo that stamps
grayscale
height-map textures onto a model's surface and turns them into real
relief -
engraved or embossed detail - either as a live preview or baked into
actual mesh
geometry.
You paint where a texture applies, stack up to **8 blended texture
layers**
(image-editor semantics: Add / Subtract / Multiply / Divide), choose how
each is
projected onto the surface (Triplanar / Cylindrical / Spherical / LSCM
unwrap /
From-view), and - for the LSCM projection - lay the charts out by hand
in a new
dockable 2D **UV Editor** pane. Coarse models can be **Subdivided** or
**Remeshed** first so there are enough vertices to carry fine detail,
and the
result is committed with **Bake**, restricted to the painted area only.
The tool only ever affects the **painted** region; everything left
unpainted
keeps its original surface, and bake blends the relief seamlessly into
it with no
remeshing or hole-filling at the seam.
---
## User-facing features
- **Paint the affected area** with Brush (circle/sphere), single-Face,
or
Connected-area flood fill; or **Select whole model** - reusing the
existing
`TriangleSelector` / `FacetsAnnotation` painting machinery, one full
mask per
layer slot.
- **Up to 8 texture layers**, each with its own paint mask, texture, and
parameters, combined in slot order like image layers.
- **Per-layer controls:** Depth, Tile size, Rotation, Midlevel
(bidirectional
emboss/engrave), Smoothing, Edge smoothing, Invert, Blend mode, Tile
(Repeat / Mirrored-repeat / decal), and Projection.
- **Projection methods:** Triplanar (blended, seam-free across sharp
edges),
Cylindrical, Spherical, **Unwrap (LSCM)** - a real CGAL conformal
parameterization - and **From view** (slide-projector decals).
- **UV Editor pane** for LSCM layers: move / rotate / scale / snap / cut
/ join
islands, average texel density, Checker and Distortion overlays, manual
mark-
seam workflow, live model update while dragging.
- **View modes:** Normal (true displaced geometry = what Bake produces),
Fast
(GPU bump-shaded approximation of the active layer), Checker, Distortion
heatmap, and an independent Wireframe toggle.
- **Mesh prep:** Subdivide (1–5* uniform 1->4 split) with cyan-wireframe
preview,
and CGAL isotropic **Remesh** to a target edge length.
- **Texture library:** 10 shipped seamless 512×512 grayscale height
maps, plus
import of any PNG/JPG/BMP (converted to an 8-bit grayscale map and
copied into
the user data dir so app updates can't clobber it).
- **Bake** runs in the background (off the UI thread); the preview is
free to
explore and only Bake changes the real mesh.
---
## How it works (implementation)
- **Bake is accumulate-then-displace and topology-preserving.** The
output mesh
has exactly the input's vertices and triangles in the same order; only
displaced vertex positions differ. Each layer is evaluated against the
**base
mesh** and folded per-vertex into a shared accumulator via its blend
mode, then
every touched vertex moves once along its precomputed undisplaced
normal. This
replaced an earlier sequential re-mesh-per-layer design that was the
root cause
of the "second layer never applies" bug and made blend modes impossible.
- **Boundary vertices are pinned.** Any vertex shared with an unpainted
triangle
is never displaced, which is what keeps bakes seamless with zero
remeshing.
- **LSCM unwrap** uses a new `MeshBoolean::cgal::parameterize_lscm()`
built on
CGAL's already-vendored `Surface_mesh_parameterization` package - **no
new
external dependency**.
- **Fast GPU preview** perturbs the shading normal from the height
gradient
(analytic mm-per-mm slope for triplanar; Mikkelsen's
screen-space-derivative
method for the conformal LSCM path), so apparent depth matches the bake.
- **Background jobs:** preview compute and bake both run off the UI
thread on the
shared job worker (queued, not `replace_job`, so a preview never cancels
an
in-flight bake); a generation counter discards stale results.
- **UV Editor** shares the app's single real `wxGLContext` and reuses
the
registered `flat`/`flat_texture` shaders; island drags update one affine
matrix
per island rather than re-uploading geometry.
---
## Backward compatibility & constraints
- **Feature is fully gated behind the new gizmo** - it adds no new
default
behavior and does not touch existing slicing, profiles, or defaults.
Models
that never open the tool are unaffected.
- **Cross-platform** - pure `libslic3r` / `libslic3r_gui` /
`libslic3r_cgal`
code; no new dependency and no `deps/` rebuild. (Built and tested on
Windows;
no platform-specific APIs introduced.)
- **`.3mf` compatibility:** **baked** relief round-trips fine, since it
becomes
ordinary mesh geometry via the existing serialization path. **Unbaked**
paint
masks and layer definitions are **not yet serialized** - see
Limitations. No
existing project data is affected.
---
## Testing
Unit tests in `tests/libslic3r/test_texture_displacement.cpp` - **run
and
passing** (7 cases, 116 assertions). Coverage:
- `decode_height_texture` round-trip
- Empty-layer no-op
- Full-cube uniform displacement
- Boundary-vertex pinning on a hand-built fan mesh
- Regression: a **second layer over the same area actually contributes**
(the
bug the bake rewrite fixed)
- Table-driven check of all four blend modes
- The lowest painted layer ignoring its blend mode
`BUILD_TESTS` is `OFF` in the checked-in cache; enable to run:
```bash
cmake -S . -B build -DBUILD_TESTS=ON
cmake --build build --config Release --target libslic3r_tests -- -m
./build/tests/libslic3r/Release/libslic3r_tests.exe "[TextureDisplacement]" --order rand
```
---
The default 0.4 mm z-hop is a 0.57 mm move along the belt axis and its
return tripped the back-step check. Shipped belt profiles print without a
z-hop, so the test does too.
A scarf joint begins one layer height below the current layer and ramps
up along the wall. On a tilted belt that start is a step backwards along
the belt axis, into the previous layer's wall at the seam: 0.283 mm per
0.2 mm layer at 45 degrees. With an aligned seam the nozzle rams the same
spot on every layer. A BabyBelt Pro benchy with seam_slope_type=external
showed 601 such back-steps from layer 107 on, and in the field the belt
"jumped backwards" and the head knocked the part loose.
Belt printers now skip the scarf in GCode::extrude_loop, and the process
tab greys the scarf controls out for them, as it already does for arc
fitting. The regression test slices a cube on a belt with the scarf
enabled and checks the belt axis never steps back by a layer pitch.
harrierpigeon