Commit Graph

1630 Commits

Author SHA1 Message Date
Ray Molenkamp
0dc484f9cc Cleanup: CMake: Modernize bf_rna dependencies
Pretty straightforward

- Remove any bf_rna paths from INC
- Add a dependency though LIB when missing

context: https://devtalk.blender.org/t/cmake-cleanup/30260

Pull Request: https://projects.blender.org/blender/blender/pulls/132413
2024-12-31 18:23:25 +01:00
Hans Goudey
e8db6b9966 Cleanup: Use attribute API for Alembic crease import 2024-12-30 11:13:47 -05:00
Bastien Montagne
694fd3bf4b Fix Alembic importer generating invalid edge crease values.
Conversion from [0-1] float value ranges to [0-255] integer char ones
was left in Alembic importer, when the internal Blender storage for
these values was converted from a char in the old `MEdge` struct to a
regular float attribute.
2024-12-30 16:25:30 +01:00
Ray molenkamp
10c5493746 Cleanup: CMake: Modernize bf_geometry dependencies
Pretty straightforward

- Remove any bf_geometry paths from INC
- Add a dependency though LIB when missing

context: https://devtalk.blender.org/t/cmake-cleanup/30260

Pull Request: https://projects.blender.org/blender/blender/pulls/132375
2024-12-28 19:58:14 +01:00
Jesse Yurkovich
da7e7a0e80 Fix: Handle null Action during armature export
Regressed during fix for [1]. A null action is possible so we need to
provide a default name when this happens.

[1] 69c63311fa

Pull Request: https://projects.blender.org/blender/blender/pulls/132381
2024-12-27 21:46:48 +01:00
Jesse Yurkovich
953fa94fb3 Cleanup: USD: Delay creation of the import hook prim_map
Delay the creation of the `prim_map` data structure until the last
possible moment. This is more efficient in the majority of cases where
no Import hooks have been defined. Additionally, it removes the need for
locking in the `read_object_data` code path once we implement concurrent
loading.

Pull Request: https://projects.blender.org/blender/blender/pulls/132360
2024-12-27 03:36:22 +01:00
Ray Molenkamp
167c15e0c0 Cleanup: CMake: Modernize bf_nodes dependencies
Pretty straightforward

- Remove any bf_nodes paths from INC
- Add a dependency though LIB when missing

context: https://devtalk.blender.org/t/cmake-cleanup/30260

Pull Request: https://projects.blender.org/blender/blender/pulls/132356
2024-12-26 19:52:49 +01:00
Aras Pranckevicius
34e24f53c8 Cleanup: STL I/O struct defaults 2024-12-26 18:24:17 +02:00
Aras Pranckevicius
55083363b8 Cleanup: OBJ export struct defaults
This makes OBJExportParamsDefault in tests code not needed anumore
2024-12-26 18:16:57 +02:00
Aras Pranckevicius
06c9a7f4ea Cleanup: PLY I/O struct defaults, C++ style enums
- Initialize PLYExportParams/PLYImportParams members
- Use enum class in ePLYVertexColorMode
- Pass import/export params as reference

This kind of fixes #126337: previously in the PLY Import node the
import paramters were all set to zero/false values, instead of sane
defaults. Which meant that it ignored vertex colors.
2024-12-26 17:54:35 +02:00
Ray Molenkamp
a0d9826b3c Cleanup: CMake: Modernize bf_imbuf dependencies
Pretty straightforward

- Remove any bf_imbuf paths from INC
- Add a dependency though LIB when missing

context: https://devtalk.blender.org/t/cmake-cleanup/30260

Pull Request: https://projects.blender.org/blender/blender/pulls/132336
2024-12-25 23:32:15 +01:00
Ray Molenkamp
4dcef4421c Cleanup: CMake: Modernize bf_functions dependencies
Pretty straightforward

- Remove any bf_functions paths from INC
- Add a dependency though LIB when missing

context: https://devtalk.blender.org/t/cmake-cleanup/30260

Pull Request: https://projects.blender.org/blender/blender/pulls/132335
2024-12-25 19:46:31 +01:00
Ray Molenkamp
a23aab3ddc Cleanup: CMake: Modernize bf_blenloader dependencies
Pretty straightforward

- Remove any bf_blenloader paths from INC
- Add a dependency though LIB when missing

context: https://devtalk.blender.org/t/cmake-cleanup/30260

Pull Request: https://projects.blender.org/blender/blender/pulls/132334
2024-12-25 18:40:41 +01:00
Ray Molenkamp
c331c6b50e Cleanup: CMake: Modernize bf_blentranslation dependencies
Pretty straightforward

- Remove any bf_blentranslation paths from INC
- Add a dependency though LIB when missing

context: https://devtalk.blender.org/t/cmake-cleanup/30260

Pull Request: https://projects.blender.org/blender/blender/pulls/132311
2024-12-25 17:40:25 +01:00
Ray Molenkamp
54604efdfd Cleanup: CMake: Modernize bf_windowmanager dependencies
Pretty straightforward

- Remove any bf_windowmanager paths from INC
- Add a dependency though LIB when missing

context: https://devtalk.blender.org/t/cmake-cleanup/30260

Pull Request: https://projects.blender.org/blender/blender/pulls/132310
2024-12-24 22:40:38 +01:00
Ray Molenkamp
a7c39896c6 Cleanup: CMake: Modernize bf_blenkernel dependencies
Pretty straightforward

- Remove any bf_blenkernel paths from INC
- Add a dependency though LIB when missing

context: https://devtalk.blender.org/t/cmake-cleanup/30260

Pull Request: https://projects.blender.org/blender/blender/pulls/132282
2024-12-23 20:08:37 +01:00
Ray Molenkamp
2992c63bc3 Cleanup: CMake: Modernize bf_bmesh dependencies
Pretty straightforward

- Remove any bf_bmesh paths from INC
- Add a dependency though LIB when missing

context: https://devtalk.blender.org/t/cmake-cleanup/30260

Pull Request: https://projects.blender.org/blender/blender/pulls/132203
2024-12-23 17:47:25 +01:00
Jesse Yurkovich
9ebb73070d USD: Enable 'quatf' Primvar types during Import
Importing USD `quatf` types was erroneously left disabled after recent
work this past summer for better attribute support. It is already
correctly enabled and validated for Export.

The `half` and `double` variants must still be skipped for now though.

Pull Request: https://projects.blender.org/blender/blender/pulls/132252
2024-12-22 23:02:41 +01:00
Jesse Yurkovich
eac1ade956 Fix #132077: Prevent stack-use-after-return inside USD_create_handle
Commit 0df5d8220b made a change to have the `USDStageReader` only keep
a reference to the ImportSettings struct. This isn't safe to do because
there's scenarios where the ImportSettings might be defined as a stack
variable but the reader outlives the lifetime of that variable. This
happens inside `USD_create_handle` where the reader is returned to the
caller for instance.

Fix this, and the original issue which lead to the change causing the
regression, by having `USDStageReader` own ImportSettings directly so
it's more obvious that it is A) tied to the lifetime of the reader and
B) can no longer become out of sync with a caller's own ImportSettings
data (since that no longer exists).

Pull Request: https://projects.blender.org/blender/blender/pulls/132095
2024-12-22 21:35:12 +01:00
Jesse Yurkovich
175ad18368 USD: Import subdivision edge creases and UV/Boundary smoothing options
Import edge crease values and properly configure any added subdivision
modifiers with correct UV and boundary settings. These were already
exported so this now completes our subdivision support.

Pull Request: https://projects.blender.org/blender/blender/pulls/131569
2024-12-20 01:31:31 +01:00
Jesse Yurkovich
a9fc9d533a USD: Optimize FCurve keyframe insertion
Building the FCurve keyframes one at a time leads to quadratic runtime
behavior due to how the underlying BezTriple array is resized in
`animrig::insert_bezt_fcurve`. Instead, pre-allocate the entire array
upfront and assign the keyframes directly since we are already iterating
our time samples in-order.

In the event that fewer keyframes are ultimately assigned, rare since
this indicates some form of bad data which we skip during iteration, we
will reallocate to the appropriate size right before recalculating the
fcurve handles.

Total import time for the 3000 frame Elephant test asset [1] drops from
~4650 ms to 120 ms, a 38x speedup. A more typical 250 frame armature
animation shows a more modest 1.5-2x reduction in overall import time.

[1] https://github.com/usd-wg/assets/tree/main/full_assets/ElephantWithMonochord

Pull Request: https://projects.blender.org/blender/blender/pulls/131921
2024-12-18 02:49:16 +01:00
Jesse Yurkovich
afe0ebeb74 Fix: properly export metaballs to USD
While adding tests I found that metaball export has been broken since
Blender 3.4. It would export each metaball geometry twice.

This looks to have been a side effect of a change to `object_dupli.cc`
which no longer sets the `no_draw` flag for metaballs[1]. With the flag
unset we would end up visiting this particular object twice.

Use a direct check for Metaballs now and add test coverage for the
scenario in general.

[1] eaa87101cd

Pull Request: https://projects.blender.org/blender/blender/pulls/131984
2024-12-16 22:11:07 +01:00
Campbell Barton
94d39aac0c Cleanup: spelling (make check_spelling_*) 2024-12-14 23:17:49 +11:00
Michael Kowalski
74512cc5cb USD: on_material_import() and texture IO hooks
Supporting a new on_material_import() USDHook callback.

Also added support for import_texture() and export_texture()
utility functions which can be called from on_material_import() and
on_material_export() Python implementations, respectively.

Pull Request: https://projects.blender.org/blender/blender/pulls/131559
2024-12-13 16:36:22 +01:00
Jesse Yurkovich
7eefbd1178 Build: USD: Small change to allow compiling against both 24.05 and 24.11
Handle the different boost python namespaces in the very recently added
code from `0df5d8220b4`

Pull Request: https://projects.blender.org/blender/blender/pulls/131817
2024-12-12 21:00:42 +01:00
Campbell Barton
84e14b21fd Unbreak building WITH_USD 2024-12-12 13:40:26 +11:00
Jesse Yurkovich
a6d4e91db8 Cleanup: USD: various non-functional changes
Tidy up:
- Use blender::Map and blender::Vector for newly created `prim_map`
- Leave bread-crumb comment for moving map creation outside of loop
- Expand UI tooltip for newly added export option

Pull Request: https://projects.blender.org/blender/blender/pulls/131770
2024-12-12 00:57:29 +01:00
Charles Flèche
0df5d8220b USD: Add new get_prim_map API callable from python on_import hooks
When importing an USD, the Blender object names do not necessarily match
Prim names:

```
#usda 1.0
def Xform "xform1"
{
  def Mesh "MyObject"  # Will be imported as "MyObject"
}
def Xform "xform2"
{
  def Mesh "MyObject"  # Will be imported as "MyObject.001"
}
def Xform "xform2"
{
  def Mesh "MyObject"  # Will be imported as "MyObject.002"
}
```

This makes it difficult in the [USD Import Hooks]
(https://docs.blender.org/api/current/bpy.types.USDHook.html) to link a
Blender object back to its source Prim for additional processing. A
typical use cases for games is to generate UVs, create and apply a
material on the fly when importing a collision shape that does not have
a visual representation (hence no materials) based on some Prim
attributes, but that the artist needs to differenciate in Blender's
viewport.

The Import context exposes a new method `get_prim_map()` that returns a
`dict` of `prim path` / `list of Blender ID`.

For example, given the following USD scene,
```
/
 |--XformThenCube [def Xform]
 |   `--Cube [def Cube]
 |--XformThenXformCube [def Xform]
 |   `--XformIntermediate [def Xform]
 |       `--Cube [def Mesh]
 |--Cube [def Cube]
 `--Material [def Material]
     `--Principled_BSDF [def Shader]
```

the `get_prim_map()` method will return a map as:

```python
@static_method
def on_import(import_context):
  pprint(import_context.get_prim_map())
```

```json
{
  "/Cube": [bpy.data.objects["Cube.002"], bpy.data.meshes["Cube.002"]],
  "/XformThenCube": [bpy.data.objects["XformThenCube"]],
  "/XformThenCube/Cube": [bpy.data.objects["Cube"], bpy.data.meshes["Cube"]],
  "/XformThenXformCube": [bpy.data.objects["XformThenXformCube"]],
  "/XformThenXformCube/XformIntermediate": [bpy.data.objects["XformIntermediate"]],
  "/XformThenXformCube/XformIntermediate/Cube": [bpy.data.objects["Cube.001"], bpy.data.meshes["Cube.001"]],
  "/Material": [bpy.data.materials["Material"]],
}
```

Co-authored-by: Odréanne Breton <odreanne.breton@ubisoft.com>
Co-authored-by: Sttevan Carnali Joga <sttevan.carnali-joga@ubisoft.com>
Co-authored-by: Charles Flèche <charles.fleche@ubisoft.com>
2024-12-11 21:36:09 +01:00
Hans Goudey
4bf34d9591 Nodes: Simplify location storage, remove hidden offfsets
Currently each node's position is stored in the coordinate space of
its parent. To find the location of a node on the canvas, we have to
apply the translation of each of its parents. Also, nodes have hidden
"offset" values used while transforming frame nodes. Together,
those made the system much more complicated than necessary,
and they made the Python API ineffective.

This commit removes usage of the offset values and moves nodes
to be stored in the "global" space of the node canvas. It also resolves
some weird behavior when resizing frame nodes, and fixes a few bugs.

The change is forward compatible, so we still write files with nodes in
the old parent-space format. In 5.0 the conversion when writing can be
removed. The existing Python API also stays the same. A new
"location_absolute" property gives node locations in global space,
and changing the old property also moves the child nodes of frames.

Resolves #92458, #72904.

Pull Request: https://projects.blender.org/blender/blender/pulls/131335
2024-12-11 21:06:41 +01:00
Jesse Yurkovich
aef11435b9 Cleanup: Move MAX_DUPLI_RECUR define from DNA to BKE
Moving MAX_DUPLI_RECUR from `DNA_object_types` to `BKE_duplilist` is
more correct organizationally and it allows some downstream consumers to
remove the inclusion of a large and unnecessary DNA header.

Archaeology reference: https://archive.blender.org/developer/D8222

Pull Request: https://projects.blender.org/blender/blender/pulls/131274
2024-12-07 03:14:49 +01:00
Jesse Yurkovich
f92bfe0f0b USD: Write sparse values for Camera, Light, and Skeleton attribute data
Make use of our sparse value writer in more places. Namely, when using
animated Camera or Light properties, this will prevent a needless stream
of unchanging values being written into the USD file [1]. Skeletons and
armatures benefit too but less so as typically the primary benefit only
applies to the comparatively small `scale` transform attribute, which
typically remains unchanged from frame to frame.

The newly added `set_attribute` common code can, and eventually will, be
used to reduce boilerplate elsewhere where we do the same sparse writing
dance.

Ref #130759

Pull Request: https://projects.blender.org/blender/blender/pulls/131333
2024-12-07 00:15:08 +01:00
Jesse Yurkovich
76c699ada5 Fix: vertex crease data was imported incorrectly from USD
While adding tests for subd import I discovered that our vertex crease
data was imported incorrectly.

This PR adds tests and fixes:
- We tried to read crease sharpness data as ints instead of floats. This
  caused the import process to early-return, meaning we never load any
  data at all
- Empty USD data would still cause us to create the `crease_vert`
  attribute unnecessarily
- Sharpness data needs clamped to 0-1 to handle USD's SHARPNESS_INFINITE
  value of 10.0
- We need to fill the `crease_vert` span with 0's since incoming USD
  data may not have values set for all the verts

Pull Request: https://projects.blender.org/blender/blender/pulls/131516
2024-12-06 22:19:31 +01:00
Jacques Lucke
eb65699715 Fix: USD: missing node tree update tag after import 2024-12-05 15:28:26 +01:00
Jesse Yurkovich
69c63311fa Fix #130907: Use Blender Action name as the UsdSkelAnimation name
Rather than using a default "Anim" name when exporting armature
animations, use the animation's Action name instead. Likewise use the
UsdSkelAnimation name for the Action's name during import.

Blendshapes/shapekeys still use the default "Anim" name as there's no
action for these situations.

Pull Request: https://projects.blender.org/blender/blender/pulls/131021
2024-12-04 23:43:07 +01:00
Jesse Yurkovich
b75b191f9f Build: USD: Small change to allow compiling against both 24.05 and 24.11
Starting with USD 24.11, the external boost dependency is being phased
out. It will instead use their own internal pxr_boost::python library.

This PR adapts the code inside `usd_hook.cc` to build and run in this
new environment.

Pull Request: https://projects.blender.org/blender/blender/pulls/131343
2024-12-04 18:45:43 +01:00
Laurynas Duburas
b13e085109 OBJ Import: Improved NURBS curve support
Adds support of NURBS weights or "rat bspline" in OBJ terms.
Tries to guess Blender knot mode better:

- Detects and closes loops. This decision is based on geometry only. No metadata is provided in OBJ for this, so importer has checkbox to disable this feature.
- Bezier knot mode allows to import circles and circular arcs.

Pull Request: https://projects.blender.org/blender/blender/pulls/131169
2024-12-03 13:16:16 +01:00
Jesse Yurkovich
d0eff5f665 Cleanup: IO Common: Use clog and fmtlib instead of streams
Use CLOG for warnings and fmtlib for developer output and string
formatting rather than the heavy `<stringstream>` machinery.

Pull Request: https://projects.blender.org/blender/blender/pulls/131126
2024-12-03 00:24:01 +01:00
Jesse Yurkovich
1868ae9366 Fix: IO: wrong ObjectIdentifier used when trying to determine parent status
The wrong ObjectIdentifier was used when trying to see if the object is
a parent to something else in the export graph. This lead to accessing
an invalid iterator which will assert with MSVC in Debug configurations.

Accidentally regressed during the review of 428ab699dc.

Pull Request: https://projects.blender.org/blender/blender/pulls/131174
2024-11-30 04:14:19 +01:00
Aras Pranckevicius
3d7359a38f Fix #130969: OBJ import shading artifacts when file contains zero-area faces
When OBJ file contains vertex normals, this can in some cases confuse
the custom loop normals code inside Blender. Since it does not simply
just use custom normals, but rather projects them into "lnor space".
But that "lnor space" calculation can go haywire sometimes, when
degenerate faces are present in the input.

Mark zero-area faces as "sharp" before doing custom normals. This will
make them not try to share the "smooth fan" lnor space with other faces,
and things will look correct.

Previously, OBJ importer was (wrongly) always setting all faces
as "sharp", which avoided this problem, but caused other issues.

Pull Request: https://projects.blender.org/blender/blender/pulls/131041
2024-11-27 22:03:15 +01:00
Hans Goudey
953c4f1599 Cleanup: Remove references to legacy Grease Pencil object
These are converted on startup to the new type. There are still
some references left, mostly where it looked like there still needs
to be changes to properly deal with the new object type.
2024-11-27 09:17:16 -05:00
Campbell Barton
0de8ae8046 Cleanup: spelling in comments 2024-11-25 13:24:46 +11:00
Jesse Yurkovich
32b9f50319 Cleanup: USD: remove another dead field from ImportSettings struct
Pull Request: https://projects.blender.org/blender/blender/pulls/130803
2024-11-23 22:04:50 +01:00
Hans Goudey
a4c9b691a0 Attributes: Add 2D 16 bit integer type
Add a `short2` attribute type, intended to store the existing
`CD_CUSTOMLOOPNORMAL` custom data type in order to move the custom
normal storage to generic attributes. This type probably won't get much
use besides that, but generally we don't have reasons not to add these
generic types, besides binary size. In the future we should consolidate
usage of `convert_to_static_type` to avoid large binary size increases
(about 700KB here) for this sort of addition.

This is the first step of #130484.

Pull Request: https://projects.blender.org/blender/blender/pulls/130530
2024-11-21 17:02:05 +01:00
Jesse Yurkovich
39e96d9c0f Fix #130155: Handle opacityThreshold controlled with individual image channels
When EEVEE next removed the Alpha Threshold option a node graph setup
was used instead. Based on a USD test asset[1] the original code was
designed around only using the Image A channel during import to wire
up the nodes. However, the other channels (R, G, or B) are just as
valid.

We now handle this by wiring up the Separate RGB node, that is already
inserted for the scenario in general, to the shader nodes handling the
threshold calculation. Also adds additional test coverage for both
export and import as well.

The Round and LessThan+OneMinus networks remain the only shapes that
will be recognized for the processing.

[1] https://github.com/usd-wg/assets/tree/main/test_assets/AlphaBlendModeTest

Pull Request: https://projects.blender.org/blender/blender/pulls/130346
2024-11-21 03:50:11 +01:00
Jesse Yurkovich
2523958e0e USD: Add support for animated point instancers
The existing point instancer reader is slightly refactored to allow for
animated setups. The primary change is simply to inherit from
`USDGeomReader` rather than `USDXformReader`. This allows access to the
`read_geometry` API used by the cache modifier.

The existing `read_object_data` method is split into two parts with
`read_geometry` loading per-frame USD data and `read_object_data`
coordinating the initial loading process, including creating the GN node
tree just once.

A new test has been added (a variation of the nested point instancer
file) with time samples on various attributes and on both point
instancers. This also fixes #129502 and the file provided in that issue.

----
The already added test file is `tests/data/usd/usd_point_instancer_anim.usda`

Pull Request: https://projects.blender.org/blender/blender/pulls/129881
2024-11-20 22:03:32 +01:00
Charles Flèche
428ab699dc USD: Add option to merge transform and shape on export
Adds the option `merge_parent_xform` to the USD export operator and
panels so the transform and shapes are merged into a single USD Prim.

Without the option (existing default), a top-level mesh would be
exported as a top-level `Xform` that has a `Mesh` child:
```
def Xform "MyBlenderMeshObject"
{
  matrix4d xformOp:transform = ...

  def Mesh "MyBlenderMeshData"
  {
  }
}
```

This matches the Blender data model, where a transformable object
contains a geometric shape (like a mesh). This structure is also very
valid in USD, where we don't want to directly instantiate geometric
primitives[1]

However, "since number of prims on a stage is one of the primary factors
that governs how USD scale"[2], to reduce the number of prims in a
stage, geometric primitives *are transformable* themselves (see the
inheritence diagram[3]).

As such, the new export option allows to export geometric primitives
without the parent transform:
```
def Mesh "MyBlenderMeshObject"
{
  matrix4d xformOp:transform = ...
}
```

This MR adds a the `is_object_data_context` flag to the
`HierarchyContext` context structure. The point of this change is to
make unambiguous in `USDHierarchyIterator::create_usd_export_context`
the fact that an `object` or a `data` is currently being exported: the
new `merge_parent_xform` option is meaningless for `object`. Only `data`
can be exported with a parent `Xform` or as a child of said `Xform`.

Ideally this flag would not be needed at all: the final USD prim path
*could* be computed in an override of the virtual
`AbstractHierarchyIterator::get_object_data_path` method. However, this
would mean that an `object` and a `data` would have the same export path.
This does not currently play well with
`AbstractHierarchyIterator::ensure_writer`, where `writers` are cached
*by their export path*: it would cache a transform writer, but will skip
the subsequent data writer.

Additionally, another new `is_parent` flag is added to handle the case
where merging the Xform is invalid: objects that are parents to other
objects should remain unmerged as otherwise that would yield invalid USD
files.

[1] https://openusd.org/release/glossary.html#usdglossary-gprim
[2] https://openusd.org/release/glossary.html#usdglossary-instancing
[3] https://openusd.org/release/api/class_usd_geom_xformable.html

Co-authored-by: Odréanne Breton <odreanne.breton@ubisoft.com>
Co-authored-by: Sttevan Carnali Joga <sttevan.carnali-joga@ubisoft.com>
Co-authored-by: Charles Flèche <charles.fleche@ubisoft.com>
2024-11-19 19:18:53 +01:00
Jesse Yurkovich
7788c85472 Cleanup: USD: remove dead fields from ImportSettings struct
Looks like the initial version of this struct was copied from Alembic.
Remove the fields that were never ultimately used and initialize the
remaining fields inline.

Pull Request: https://projects.blender.org/blender/blender/pulls/130492
2024-11-19 08:16:09 +01:00
Jesse Yurkovich
704d34fe0f Fix: properly save in-memory and packed textures during USD export
While adding test coverage for in-memory and packed texture scenarios, I
found that UDIMs were not being handled correctly in both cases. For
in-memory scenarios the per-tile generated/dirty status was not taken
into account. For packed scenarios the wrong filename substitutions were
being used.

This fixes both of these cases and adds test coverage for these
scenarios now. Both relative and absolute path options are validated.

Note: Both in-memory and packed images behave incorrectly when using the
'KEEP' and 'PRESERVE' texture export modes, so those remain untested
currently. A design on exactly what should happen in these modes is TBD.

Pull Request: https://projects.blender.org/blender/blender/pulls/130391
2024-11-17 21:53:35 +01:00
Jesse Yurkovich
e68897e117 Fix: prevent duplicate shader node links during USD import
When reading UsdPreviewSurface materials from USD files, duplicate links
between nodes would often result. This typically occurs between the
Image node and its upstream UV Mapping node, or between the Image node
and a downstream Separate RGB node. As processing progresses, we
de-duplicate the nodes themselves as each new input/output socket is
discovered. However, we would unconditionally add a link between the
nodes even if we've already added one.

Cycles will complain about this situation and it's obviously incorrect:
`Cycles shader graph connect: input already connected.`

As most UsdPreviewSurface material networks are all fairly small
(<10 links total) I'm not worried about the cost of counting the links
at this point.

Pull Request: https://projects.blender.org/blender/blender/pulls/130356
2024-11-16 04:12:07 +01:00
Hans Goudey
f879d23237 Cleanup: Use const for evaluated pre-modified mesh accessor
Conceptually this shouldn't be changed after it's created for the
first time.
2024-11-14 15:45:44 -05:00