The `pxr::VtArray<T>` type is based on a copy-on-write scheme that is
very easy to trigger unnecessarily because of how the C++ type system
works[1].
Here we bypass unneeded copies by ensuring we always call the `const`
version of various accessor functions. The offending call-sites were
found by using the `VT_LOG_STACK_ON_ARRAY_DETACH_COPY` env variable.
This yields a very small 2-3% performance benefit when loading in a
typical, mixed-use, asset like e.g. the "4004 Moore Lane" scene.
[1] https://github.com/PixarAnimationStudios/OpenUSD/blob/dev/pxr/base/vt/array.h#L139
Pull Request: https://projects.blender.org/blender/blender/pulls/136014
This PR adds support for 2 additional USD Prim Shape Schemas :
* Cylinder_1
* Capsule_1
Additional tests will be added afterwards but a simple test is simply to
import the resulting file:
```python
from pxr import Usd, UsdGeom
stage = Usd.Stage.CreateNew('shapes.usda')
UsdGeom.Xform.Define(stage, '/world')
UsdGeom.Cylinder_1.Define(stage, '/world/cylinder_1')
UsdGeom.Capsule_1.Define(stage, '/world/capsule_1')
stage.GetRootLayer().Save()
```
Linked issue : https://projects.blender.org/blender/blender/issues/134138
Co-authored-by: Nig3l <nig3lpro@gmail.com>
Pull Request: https://projects.blender.org/blender/blender/pulls/134944
Implement the USD Plane Shape for import, mirroring what was done for
the others. See #134138
Additional tests will be added afterwards but a simple test is simply to
import the resulting file:
```python
from pxr import Usd, UsdGeom
stage = Usd.Stage.CreateNew('plane.usd')
xform_prim = UsdGeom.Xform.Define(stage, '/world')
plane_prim = UsdGeom.Plane.Define(stage, '/world/plane')
stage.GetRootLayer().Save()
```
Co-authored-by: Nig3l <nig3lpro@gmail.com>
Pull Request: https://projects.blender.org/blender/blender/pulls/134275
- Remove redundant .HasValue() calls
We are calling `GetPrimvarsWithValues` which will do the HasValue
checks for us already.
- Consistently skip non-array primvars
We only want to import in the array attributes. Consistently check for
this in each of our loops.
Pull Request: https://projects.blender.org/blender/blender/pulls/132816
Color primvars/attributes were historically treated as a special case
for both import and export. This was mostly done to align with how
painting and viewport display works in Blender. Export would generally
ignore color attributes except when they were found on a Mesh's Point or
FaceCorner domains. And import went out of its way to map incoming color
primvars to the FaceCorner domain in more situations than necessary.
To facilitate better roundtripping in Blender<=>USD workflows, and to
reduce code duplication, this PR teaches the common attribute utilities
how to handle color types. The color attributes will now work on all
relevant Mesh and Curve domains.
There were tests in place for this already but they were set to verify
the inverse state, i.e. the technically broken state, until this could
be fixed.
There remains one special case: "displayColor" primvars and attributes.
The "displayColor" is a special primvar in USD and is the de-facto way
to set a simple viewport color in that ecosystem. It must also be a
color3f type. In order to not regress import, if a "displayColor"
primvar is found on the Face domain we will map it to FaceCorner instead
so it can be displayed in the viewport; which has been the case for the
past several releases. We can drop this special-case if/when Blender can
display Face colors through the Viewport Shading "Attribute" color type.
Additionally, Blender will export this, and only this, color attribute
as a color3f.
Note: As was the case prior to this PR, the following 2 discrepancies
still prevent "perfect" round-trips:
- USD does not have an equivalent to Blender's byte colors; they are
treated as float during IO
- Blender does not have an equivalent to USD's color3 types; they are
treated as color4 during IO
Pull Request: https://projects.blender.org/blender/blender/pulls/127784
- Use `lookup_or_add_for_write_only_span` in more places
- Use `copy_from` when reading in positions for the few readers where
this wasn't already being done
- Remove manual memory management when processing corner normals
Pull Request: https://projects.blender.org/blender/blender/pulls/128043
Apply `const` to variables, arguments, and methods. Also includes a few
variable shadowing changes that were noticed along the way.
All changes should have no user visible effects.
Pull Request: https://projects.blender.org/blender/blender/pulls/125873
This factors out the current set of attribute-to-primvar functions
inside the USD mesh reader/writer so we can use them elsewhere.
These new functions will be used for PointCloud attribute reading and
Curve attribute reading and writing in follow up changes.
Pull Request: https://projects.blender.org/blender/blender/pulls/121145
Blender USD import already supports the displayColor primvar, when it is
specified on Mesh prims. These colors are visible in the viewport when
the viewport shading color type is set to Attribute.
This PR extends this displayColor primvar support to also work with the
various shape prims, such as Box, Sphere, etc.
The original displayColor support was implemented in USDMeshReader.
Because USDShapeReader is a sibling to to USDMeshReader, and
USDShapeReader first converts shapes to a Mesh, we have factored out the
mutually beneficial code from usd_reader_mesh.cc into a new usd_mesh_utils.cc.
For now only the displayColor primvar is supported on shapes, but this
could be easily extended in a future PR.
Authored by Apple: Matt McLin
Co-authored-by: Michael Kowalski <makowalski@nvidia.com>
Pull Request: https://projects.blender.org/blender/blender/pulls/120236
Reduce dependence on Blender headers as much as possible and move closer
to an include-what-you-use setup.
- Removes unnecessary includes
- Replaces some includes with more appropriate, narrower, substitutes
- Removes unnecessary forward declarations
Pull Request: https://projects.blender.org/blender/blender/pulls/118308
This rewrites the Alembic and USD data importers to work with and
output GeometrySets instead of Meshes.
The main motivation for this change is to be able to import properly
point clouds, which are currently imported as Meshes, and curves
data, which suffer from a lot of issues due to limitations of
legacy curves structures (fixed by the new curves data-block) and are
also converted to Meshes. Further, for Curves, it will allow importing
arbitrary attributes.
This patch was primarily meant for Alembic, but changes to USD import
were necessary as they share the same modifier.
For Alembic:
There should be no behavioral changes for Meshes
Curves are imported as the new Curves object type
Points are imported as PointClouds
For USD:
There should be no behavioral changes for Meshes
Curves are imported as the new Curves object type
Note that the current USD importer does not support loading PointClouds,
so this patch does not add support for it.
For both Alembic and USD, knots arrays are not read anymore, as the new
Curves object does not expose the ability to set them. Improvements can
be made in the future if and when example assets are provided.
This fixes at least the following:
#58704: Animated Alembic curves don't update on render
#112308: Curves have offset animations (alembic / USD)
#118261: wrong motion blur from usd in cycles and reverting to the first
frame when disabeling motion blur
Co-authored-by: Jesse Yurkovich <jesse.y@gmail.com>
Pull Request: https://projects.blender.org/blender/blender/pulls/115623
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.
Use the standard "elements_num" naming, and use the "corner" name rather
than the old "loop" name: `verts_num`, `edges_num`, and `corners_num`.
This matches the existing `faces_num` field which was already renamed.
Pull Request: https://projects.blender.org/blender/blender/pulls/116350
Calling `WM_report` & co API from wmJob worker thread is utterly unsafe,
and should never have been done. It 'worked' so far presumably because
worker threads were barely (if ever) reporting anything that way, but
now USD IO code is spamming reports in some cases, leading to fairly
common crashes.
Pull Request: https://projects.blender.org/blender/blender/pulls/113883
Implements part of #101689.
The "poly" name was chosen to distinguish the `MLoop` + `MPoly`
combination from the `MFace` struct it replaced. Those two structures
persisted together for a long time, but nowadays `MPoly` is gone, and
`MFace` is only used in some legacy code like the particle system.
To avoid unnecessarily using a different term, increase consistency
with the UI and with BMesh, and generally make code a bit easier to
read, this commit replaces the `poly` term with `poly`. Most variables
that use the term are renamed too. `Mesh.totface` and `Mesh.fdata` now
have a `_legacy` suffix to reduce confusion. In a next step, `pdata`
can be renamed to `face_data` as well.
Pull Request: https://projects.blender.org/blender/blender/pulls/109819
A lot of files were missing copyright field in the header and
the Blender Foundation contributed to them in a sense of bug
fixing and general maintenance.
This change makes it explicit that those files are at least
partially copyrighted by the Blender Foundation.
Note that this does not make it so the Blender Foundation is
the only holder of the copyright in those files, and developers
who do not have a signed contract with the foundation still
hold the copyright as well.
Another aspect of this change is using SPDX format for the
header. We already used it for the license specification,
and now we state it for the copyright as well, following the
FAQ:
https://reuse.software/faq/
The typical order is vertex, edge, face(polygon), corner(loop), but in
these three functions polys and loops were reversed. Also use more
typical "num" variable names rather than "len"
Implements #95967.
Currently the `MPoly` struct is 12 bytes, and stores the index of a
face's first corner and the number of corners/verts/edges. Polygons
and corners are always created in order by Blender, meaning each
face's corners will be after the previous face's corners. We can take
advantage of this fact and eliminate the redundancy in mesh face
storage by only storing a single integer corner offset for each face.
The size of the face is then encoded by the offset of the next face.
The size of a single integer is 4 bytes, so this reduces memory
usage by 3 times.
The same method is used for `CurvesGeometry`, so Blender already has
an abstraction to simplify using these offsets called `OffsetIndices`.
This class is used to easily retrieve a range of corner indices for
each face. This also gives the opportunity for sharing some logic with
curves.
Another benefit of the change is that the offsets and sizes stored in
`MPoly` can no longer disagree with each other. Storing faces in the
order of their corners can simplify some code too.
Face/polygon variables now use the `IndexRange` type, which comes with
quite a few utilities that can simplify code.
Some:
- The offset integer array has to be one longer than the face count to
avoid a branch for every face, which means the data is no longer part
of the mesh's `CustomData`.
- We lose the ability to "reference" an original mesh's offset array
until more reusable CoW from #104478 is committed. That will be added
in a separate commit.
- Since they aren't part of `CustomData`, poly offsets often have to be
copied manually.
- To simplify using `OffsetIndices` in many places, some functions and
structs in headers were moved to only compile in C++.
- All meshes created by Blender use the same order for faces and face
corners, but just in case, meshes with mismatched order are fixed by
versioning code.
- `MeshPolygon.totloop` is no longer editable in RNA. This API break is
necessary here unfortunately. It should be worth it in 3.6, since
that's the best way to allow loading meshes from 4.0, which is
important for an LTS version.
Pull Request: https://projects.blender.org/blender/blender/pulls/105938
Implements #102359.
Split the `MLoop` struct into two separate integer arrays called
`corner_verts` and `corner_edges`, referring to the vertex each corner
is attached to and the next edge around the face at each corner. These
arrays can be sliced to give access to the edges or vertices in a face.
Then they are often referred to as "poly_verts" or "poly_edges".
The main benefits are halving the necessary memory bandwidth when only
one array is used and simplifications from using regular integer indices
instead of a special-purpose struct.
The commit also starts a renaming from "loop" to "corner" in mesh code.
Like the other mesh struct of array refactors, forward compatibility is
kept by writing files with the older format. This will be done until 4.0
to ease the transition process.
Looking at a small portion of the patch should give a good impression
for the rest of the changes. I tried to make the changes as small as
possible so it's easy to tell the correctness from the diff. Though I
found Blender developers have been very inventive over the last decade
when finding different ways to loop over the corners in a face.
For performance, nearly every piece of code that deals with `Mesh` is
slightly impacted. Any algorithm that is memory bottle-necked should
see an improvement. For example, here is a comparison of interpolating
a vertex float attribute to face corners (Ryzen 3700x):
**Before** (Average: 3.7 ms, Min: 3.4 ms)
```
threading::parallel_for(loops.index_range(), 4096, [&](IndexRange range) {
for (const int64_t i : range) {
dst[i] = src[loops[i].v];
}
});
```
**After** (Average: 2.9 ms, Min: 2.6 ms)
```
array_utils::gather(src, corner_verts, dst);
```
That's an improvement of 28% to the average timings, and it's also a
simplification, since an index-based routine can be used instead.
For more examples using the new arrays, see the design task.
Pull Request: https://projects.blender.org/blender/blender/pulls/104424
Refactoring mesh code, it has become clear that local cleanups and
simplifications are limited by the need to keep a C public API for
mesh functions. This change makes code more obvious and makes further
refactoring much easier.
- Add a new `BKE_mesh.hh` header for a C++ only mesh API
- Introduce a new `blender::bke::mesh` namespace, documented here:
https://wiki.blender.org/wiki/Source/Objects/Mesh#Namespaces
- Move some functions to the new namespace, cleaning up their arguments
- Move code to `Array` and `float3` where necessary to use the new API
- Define existing inline mesh data access functions to the new header
- Keep some C API functions where necessary because of RNA
- Move all C++ files to use the new header, which includes the old one
In the future it may make sense to split up `BKE_mesh.hh` more, but for
now keeping the same name as the existing header keeps things simple.
Pull Request: https://projects.blender.org/blender/blender/pulls/105416
Currently the shade smooth status for mesh faces is stored as part of
`MPoly::flag`. As described in #95967, this moves that information
to a separate boolean attribute. It also flips its status, so the
attribute is now called `sharp_face`, which mirrors the existing
`sharp_edge` attribute. The attribute doesn't need to be allocated
when all faces are smooth. Forward compatibility is kept until
4.0 like the other mesh refactors.
This will reduce memory bandwidth requirements for some operations,
since the array of booleans uses 12 times less memory than `MPoly`.
It also allows faces to be stored more efficiently in the future, since
the flag is now unused. It's also possible to use generic functions to
process the values. For example, finding whether there is a sharp face
is just `sharp_faces.contains(true)`.
The `shade_smooth` attribute is no longer accessible with geometry nodes.
Since there were dedicated accessor nodes for that data, that shouldn't
be a problem. That's difficult to version automatically since the named
attribute nodes could be used in arbitrary combinations.
**Implementation notes:**
- The attribute and array variables in the code use the `sharp_faces`
term, to be consistent with the user-facing "sharp faces" wording,
and to avoid requiring many renames when #101689 is implemented.
- Cycles now accesses smooth face status with the generic attribute,
to avoid overhead.
- Changing the zero-value from "smooth" to "flat" takes some care to
make sure defaults are the same.
- Versioning for the edge mode extrude node is particularly complex.
New nodes are added by versioning to propagate the attribute in its
old inverted state.
- A lot of access is still done through the `CustomData` API rather
than the attribute API because of a few functions. That can be
cleaned up easily in the future.
- In the future we would benefit from a way to store attributes as a
single value for when all faces are sharp.
Pull Request: https://projects.blender.org/blender/blender/pulls/104422
This commit adds the ability to import USD Shape primitives (Gprims).
They are imported as Blender Meshes using the USD API to convert, so
that they appear the same as they would in other applications. USD
Shapes are important in many workflows, particularly in gaming, where
they are used for stand-in geometry or for collision primitives.
Pull Request #104707
