Previously, the lifetimes of anonymous attributes were determined by
reference counts which were non-deterministic when multiple threads
are used. Now the lifetimes of anonymous attributes are handled
more explicitly and deterministically. This is a prerequisite for any kind
of caching, because caching the output of nodes that do things
non-deterministically and have "invisible inputs" (reference counts)
doesn't really work.
For more details for how deterministic lifetimes are achieved, see D16858.
No functional changes are expected. Small performance changes are expected
as well (within few percent, anything larger regressions should be reported as
bugs).
Differential Revision: https://developer.blender.org/D16858
Previously, things like materials, symmetry, and selection options
stored on `Curves` weren't copied to the result in nodes like the
subdivide and resample nodes. Now they are, which fixes some
unexpected behavior and allows visualization of the sculpt mode
selection.
In the realize instances and join nodes the behavior is the same as
for meshes, the parameters are taken from the first (top) input.
I also refactored some functions to return a `CurvesGeometry` by-value,
which makes it the responsibility of the node to copy the parameters.
That should make the algorithms more reusable in other situations.
Differential Revision: https://developer.blender.org/D15408
This commit moves the subdivide curve node implementation to the
geometry module, changes it to work on the new curves data-block,
and adds support for Catmull Rom curves. Internally I also added
support for a curve domain selection. That isn't used, but it's
nice to have the option anyway.
Users should notice better performance as well, since we can avoid
many small allocations, and there is no conversion to and from the
old curve type.
The code uses a similar structure to the resample node (60a6fbf5b5)
and the set type node (9e393fc2f1). The resample curves node can be
restructured to be more similar to this soon though.
Differential Revision: https://developer.blender.org/D15334
