There is a corner case where one side of a quad needs splitting and the other
side has only one segment. Previously this would produce either gaps or after
recent changes to stitch together geometry, uninitialized memory.
Now solve this by splitting into triangular patches, as suggested in the
DiagSplit paper. These triangular patches can be further subdivided themselves.
Dicing has special cases for 1 or 2 segments on edges. For more segments it
works the same as: quad dicing: A regular inner triangle grid stitched to the
outer edges.
Fix#136973: Inconsistent results with adaptive subdivision
Pull Request: https://projects.blender.org/blender/blender/pulls/139062
* Perform attribute interpolation as part of dicing.
* Remove temporary subd uv and face index attributes.
On a MacBook M3 with 12 P-cores and 4 E-cores, these changes overall give
a 10x-14x speedup on various scenes. Note that splitting is still single
threaded and can be expensive, and UV subdivision can be optimized more.
Pull Request: https://projects.blender.org/blender/blender/pulls/136411
* Move dicing out of DiagSplit, caller now uses EdgeDice
* Merge, rename and reorder various EdgeDice functions
* Compute triangle indices for subpatches in advance
Pull Request: https://projects.blender.org/blender/blender/pulls/136411
* Share vertices between patches instead of using stitch map
* Switch to OpenSubdiv compatible counter-clockwise indexing
* Simplify patch edge reverse direction logic
* Add more comments to splitting and dicing
Pull Request: https://projects.blender.org/blender/blender/pulls/135681
* Add SubdAttributeInterpolation class for linear attribute interpolation.
* Dicing computes ptex UV and face ID for interpolation.
* Simplify mesh storage of subd primitive counts
* Remove kernel code for subd attribute interpolation
* Remove patch table packing and upload
The old optimization adds a fair amount of complexity to the kernel, affecting
performance even when not using the feature. It's also not that useful as it
does not work for UVs that needs special interpolation. With this simpler code
it should be easier to make it feature complete.
Pull Request: https://projects.blender.org/blender/blender/pulls/135681
Check was misc-const-correctness, combined with readability-isolate-declaration
as suggested by the docs.
Temporarily clang-format "QualifierAlignment: Left" was used to get consistency
with the prevailing order of keywords.
Pull Request: https://projects.blender.org/blender/blender/pulls/132361
For example
```
OIIOOutputDriver::~OIIOOutputDriver()
{
}
```
becomes
```
OIIOOutputDriver::~OIIOOutputDriver() {}
```
Saves quite some vertical space, which is especially handy for
constructors.
Pull Request: https://projects.blender.org/blender/blender/pulls/105594
* Replace license text in headers with SPDX identifiers.
* Remove specific license info from outdated readme.txt, instead leave details
to the source files.
* Add list of SPDX license identifiers used, and corresponding license texts.
* Update copyright dates while we're at it.
Ref D14069, T95597
Remove prefix of filenames that is the same as the folder name. This used
to help when #includes were using individual files, but now they are always
relative to the cycles root directory and so the prefixes are redundant.
For patches and branches, git merge and rebase should be able to detect the
renames and move over code to the right file.