This adds the processing required to import and export simple material graphs utilizing the UsdUVTexture outputs channels.
If only r, g or b are specified as output, we hook up a `Separate Color` node and connect the appropriate channel from there.
(if a is specified as output, the Alpha output of an image texture node was used already)
On the export side, we traverse from the socket to the image texture node, and if a `Separate Color` on the way, we are using the channel from there to put on the output.
https://openusd.org/release/spec_usdpreviewsurface.html#texture-reader
Pull Request: https://projects.blender.org/blender/blender/pulls/117901
This header is for 'internal' USD code only (also needed by the hydra
code), and uses references to the USD library itself, so its previous
name was a bit too generic.
First step to move the main public Blender USD API header (`usd.h`) to cpp.
This adds a new `ModifierData.persistent_uid` integer property with the following properties:
* It's unique within the object.
* Match between the original and evaluated object.
* Stable across Blender sessions.
* Stable across renames and reorderings of modifiers.
Potential use-cases:
* Everywhere where we currently use the name as identifier. For example,
`ModifierComputeContext` and `ModifierViewerPathElem`.
* Can be used as part of a key in `IDCacheKey` to support caches that stay
in-tact across undo steps.
* Can be stored in the `SpaceNode` to identify the modifier whose geometry node
tree is currently pinned (this could use the name currently, but that hasn't been
implemented yet).
This new identifier has some overlap with `ModifierData.session_uid`, but there
are some differences:
* `session_uid` is unique within the entire Blender session (except for duplicates
between the original and evaluated data blocks).
* `session_uid` is not stable across Blender sessions.
Especially due to the first difference, it's not immediately obvious that the new
`persistent_uid` can fulfill all use-cases of the existing `session_uid`. Nevertheless,
this seems likely and will be cleaned up separately.
Unfortunately, there is not a single place where modifiers are added to objects currently.
Therefore, there are quite a few places that need to ensure valid identifiers. I tried to catch
all the places, but it's hard to be sure. Therefore, I added an assert in `object_copy_data`
that checks if all identifiers are valid. This way, we should be notified relatively quickly if
issues are caused by invalid identifiers.
Pull Request: https://projects.blender.org/blender/blender/pulls/117347
Added support for defining an on_import() function in
bpy.types.USDHook subclasses. If on_import() is defined
on a given USD hook, it will be invoked in import_endjob().
The implementation closely follows the existing design of
export hooks. USDHook.on_import() takes as an argument
an instance of an internally defined USDSceneImportContext
class which provides an accessor to the USD stage.
Also updated the USDHook documentation with an example
on_import() callback implementation.
Pull Request: https://projects.blender.org/blender/blender/pulls/117822
This adds the processing required to import and export, simple, material
graphs utilizing the UsdUVTexture Scale and Bias inputs.
Since Blender does not have equivalent inputs on its Image node, a
Multiply-Add node is used instead. This matches the calculation as per
the UsdPreviewSurface spec[1]
A complicating factor here is when these two inputs are used for normal
map textures. The Scale and Bias inputs are authored in such a way to
take the [0, 1] image data and expand into the [-1, 1] tangent space
range as per the spec. However, the Blender Normal Map node expects to
do this transformation itself. The processing in this patch needs to
account for this. For the case of normal maps it will:
- Apply the Scale-Bias calculation directly as authored
- Apply an additional transform to move from [-1, 1] back into [0, 1]
- Feeds this into the Normal Map node
This processing extends to Export as well. During material graph
traversal we need to "skip" the middle adjustment transform and only
export the "real" Scale-Bias data. Traversing the graph like this can be
error prone but is probably the best we can do without having a native
Scale-Bias concept on Blender's Image node.
[1] https://openusd.org/release/spec_usdpreviewsurface.html#texture-reader
Pull Request: https://projects.blender.org/blender/blender/pulls/115224
Added support for static point instancing import.
Added a new USDPointInstancerReader class to import UsdGeomPointInstancer
primitives as Point Clouds with geometry node modifiers that use
Instance on Points geometry nodes to instance collections containing
prototype geometry.
Added logic to the USDStageReader class to traverse the USD stage to
create readers for point instancer prototypes.
Extended USDStageReader::collect_readers() to take arguments to include
undefined prims and to exclude a set of specified prims when traversing
the stage. Allowing traversing undefined prims is necessary because
prototype prims may be specified as "overs" in the USD stage.
Added a USDPrimReader::is_in_instancer_proto_ boolean flag which
identifies readers of prims that are in point instancer prototypes.
The flag simplifies management of collections and is used to
determine whether global transforms should be applied to root objects.
Limitation: point cloud animation is not yet supported.
This partially addresses https://projects.blender.org/blender/blender/issues/96747.
Co-authored-by: Michael Kowalski <makowalski@nvidia.com>
Pull Request: https://projects.blender.org/blender/blender/pulls/113107
- Only calculate the necessary normals based on smooth/flat/mixed shading
- Use cached face normals instead of computing them
- Use a `VectorSet` for deduplication instead of a `Map`
- Deduplicate vertex normals and store indices in separate loops
- Avoid unnecessary duplication of face normal indices
- Inline simple function for slicing index span
Export time (ms) of 1.8m vertex mesh:
| Normals Domain | Before | After |
| --------------- | ------ | ----- |
| Face (flat) | 559 | 469 |
| Vertex (smooth) | 659 | 466 |
| Corner (mixed) | 656 | 640 |
The change of using normals from different domains and using a
VectorSet for de-duplication change the order of normals in the OBJ
files. Other than that, the results should be unchanged.
Fixes#117510
Pull Request: https://projects.blender.org/blender/blender/pulls/117522
Remove the need for the `calc_vertex_coords` function by combining
the scale into the existing transform needed to export vertex positions
in global space. This simplifies code and may slightly improve performance
(I only observed a few percent difference in the positions export, which is
not a slower part of the export).
- Use Span where ownership is unnecessary
- Use Array when dynamic growth is unnecessary
- Use Vector in all other cases
Also remove unnecessary namespace specification.
Straightforward change from usage of iostream to CLOG.
Using CLOG unifies info/warning/error logging under a common
infrastructure that provides facilities for standardized filtering,
categorization, and printing. It also removes direct dependencies on
`<iostream>` which can be detrimental to compile times.
Pull Request: https://projects.blender.org/blender/blender/pulls/117429
`BKE_object_get_pre_modified_mesh` returns curve object data, later
accessing non-existing edge/face data triggered the crash.
`apply_modifiers` seems valid for mesh data only.
Pull Request: https://projects.blender.org/blender/blender/pulls/117471
The term `PIL` stands for "platform independent library." It exists since the `Initial Revision`
commit from 2002. Nowadays, we generally just use the `BLI` (blenlib) prefix for such code
and the `PIL` prefix feels more confusing then useful. Therefore, this patch renames the
`PIL` to `BLI`.
Pull Request: https://projects.blender.org/blender/blender/pulls/117325
There's been feedback that placing them inside a Scope better aligns
with other DCCs and makes some aspects of tooling more consistent in the
ecosystem.
Note: it was not a spec violation to have the typeless def that we used
before.
Pull Request: https://projects.blender.org/blender/blender/pulls/116460
The previous commit introduced a new `RPT_()` macro to translate
strings which are not tooltips or regular interface elements, but
longer reports or statuses.
This commit uses the new macro to translate many strings all over the
UI.
Most of it is a simple replace from `TIP_()` or `IFACE_()` to
`RPT_()`, but there are some additional changes:
- A few translations inside `BKE_report()` are removed altogether
because they are already handled by the translation system.
- Messages inside `UI_but_disable()` are no longer translated
manually, but they are handled by a new regex in the translation
system.
Pull Request: https://projects.blender.org/blender/blender/pulls/116804
Pull Request: https://projects.blender.org/blender/blender/pulls/116804
This fixes an issue where a CacheFile was always created for the USD
file, causing USD_create_handle() to be called unnecessarily even if the
USD does not have animating meshes or transforms.
This bug would sometimes result in the stage remaining open in a
CacheArchiveHandle after import (because the CacheFile is never
freed), preventing the USD from being reloaded from disk.
The cache file is now accessible to readers through an
ImportSettings::get_cache_file function wrapper which creates a
CacheFile as needed, the first time the function is called.
The allocated CacheFile pointer is now stored in a new
ImportJobData::cache_file member.
Pull Request: https://projects.blender.org/blender/blender/pulls/116242
