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/
This function replaced the evaluated mesh with a new one with the given
custom data type mask. That doesn't work in general anymore for a few
reasons: the increased dependence on named attributes (a opposed to
custom data types), and the "all or nothing" approach to reevaluating
the depsgraph. Other objects might depend on the object's evaluated
geometry, so it shouldn't just be replaced. Pushed a bit further, this could
give nice simplifications to mesh modifier evaluation.
There are two breaking changes, `bmesh_from_object` and BVH tree
`FromObject` require the source object to have a proper evaluated
mesh now.
If this causes a regression, it's likely that the object is missing
an update tag when a mode is entered that requires extra evaluated data.
Pull Request: https://projects.blender.org/blender/blender/pulls/106186
For derived mesh triangulation information, currently the three face
corner indices are stored in the same struct as index of the mesh
polygon the triangle is part of. While those pieces of information are
often used together, they often aren't, and combining them prevents
the indices from being used with generic utilities. It also means that
1/3 more memory has to be written when recalculating the triangulation
after deforming the mesh, and that the entire triangle data has to be
read when only the polygon indices are needed.
This commit splits the polygon index into a separate cache on `Mesh`.
The triangulation data isn't saved to files, so this doesn't affect
.blend files at all.
In a simple test deforming a mesh with geometry nodes, the time used
to recalculate the triangulation reduced from 2.0 ms to 1.6 ms,
increasing overall FPS from 14.6 to 15.
Pull Request: https://projects.blender.org/blender/blender/pulls/106774
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
