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
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
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
Change to map the USD "varying" interpolation type to Blender's
"Corner" domain type when importing mesh attributes. This fixes
value count mismatch errors when importing USD attributes with
varying interpolation.
Note that, for meshes, "varying" and "faceVarying" interpolation
are essentially the same in practice.
Pull Request: https://projects.blender.org/blender/blender/pulls/116955
The same is done for other geometry types. This allows us to use C++ types in
the run-time data more easily and avoids dumping runtime data into .blend files.
Pull Request: https://projects.blender.org/blender/blender/pulls/116840
Bundling many tests in a single binary reduces build time and disk space
usage, but is less convenient for running individual tests command line
as filter flags need to be used.
This adds WITH_TESTS_SINGLE_BINARY to generate one executable file per
source file. Note that enabling this option requires a significant amount
of disk space.
Due to refactoring, the resulting ctest names are a bit different than
before. The number of tests is also a bit different depending if this
option is used, as one uses gtests discovery and the other is organized
purely by filename, which isn't always 1:1.
Co-authored-by: Sergey Sharybin <sergey@blender.org>
Pull Request: https://projects.blender.org/blender/blender/pulls/114604
Along with the 4.1 libraries upgrade, we are bumping the clang-format
version from 8-12 to 17. This affects quite a few files.
If not already the case, you may consider pointing your IDE to the
clang-format binary bundled with the Blender precompiled libraries.
New functionality to export armatures and shape keys as USD
skeletons and blend shapes.
Added "Armature", "Only Deform Bones" and "Shape Key" USD export options.
Added USDArmatureWriter class.
Extended USDMeshWriter to write skinned meshes for binding
with skeletons and 'neutral' meshes with blend shape targets.
Specifically, when exporting an armature, a skinned mesh is written
in its pre-modified rest position. When exporting to blend shapes,
a mesh with shape keys is saved with its vertices in the shape key
basis shape position.
Added USDHierarchyIterator::process_usd_skel() function to
finish processing skeleton and blend shape export after the
writer instances completed writing. This is necessary because
some of the export operations require processing multiple prims
at once.
Extended USDTransformWriter::do_write() to write transforms
sparsely, to avoid saving redundant transform values when exporting
armatures.
Added a create_skel_roots() function, called on the stage at the
end of the export. This function attempts to ensure that skinned
prims and skeletons are encapsulated under SkelRoot primitives,
which is required in USD for correct skinning behavior.
When exporting blend shape animations for multiple meshes bound
to a single skeleton, we need to merge the blend shape time samples
of the different meshes into a single animation primitive at the end
of the export. This requires some tricky book keeping, where the weight
time samples for a given mesh are initially saved by the mesh writer to a
temporary attribute on the mesh and are later copied to the animation
primitive as one of the final steps.
When writing blend shapes and skinned meshes, the pre-modified mesh
is exported. This is to ensure that the number of blend shape offsets
matches the number of points, and so that the skinned mesh is saved in
its rest position.
Because the pre-modified mesh must be exported, modifiers in addition
to Armature modifiers will not be applied. This still allows the round trip
UsdSkel -> Blender -> UsdSkel, but some additional setup might be
required to export to UsdSkel when there are multiple modifiers (for
example, applying mirroring modifiers that precede the armature
modifier).
Exporting bendy bones or absolute shape keys isn't currently
supported.
Co-authored-by: Charles Wardlaw <charleswardlaw@noreply.localhost>
Pull Request: https://projects.blender.org/blender/blender/pulls/111931
Added support for importing USD instanceable primitives into Blender
as collection instances.
Added a new USDInstanceReader class for importing USD
instances as Blender objects that instance collections containing
prototype data.
Extended the USDStageReader to read USD prototype prims into
collections that are instanced on the objects created by the instance
readers.
Removed the "Import Instance Proxies" import option.
Importing instances is enabled with a new "Scene Instancing" import
option, which is true by default. If this option is off, instances will be
imported as copies (which is the functionality previously enabled by
the "Import Instance Proxies" option).
Removed calls to UsdSkelBindingAPI::Apply() in the skeleton and
blend shape import code, as these calls were unnecessary and were
generating errors when importing instance prototypes with UsdSkel
data.
Nested instancing and animated prototypes are supported.
Pull Request: https://projects.blender.org/blender/blender/pulls/115076
Some common headers were including this. Separating the includes
will ideally lead to better conceptual separation between CustomData
and the attribute API too. Mostly the change is adding the file to
places where it was included indirectly before. But some code is
shuffled around to hopefully better places as well.
Except for vertex groups and a few older color types, these
are generally replaced by newer generic attribute types.
Also remove some includes of DNA_mesh_types.h, since it's
included indirectly by BKE_mesh.hh currently.
