This was actually rather hairy, this code is huge and complicated, easy
to make mistakes...
Good thing is, it will allow for significant simplification and more
(name) cleanup in following commits ;)
The depsgraph was always created within a fixed evaluation context. Passing
both risks the depsgraph and evaluation context not matching, and it
complicates the Python API where we'd have to expose both which is not so
easy to understand.
This also removes the global evaluation context in main, which assumed there
to be a single active scene and view layer.
Differential Revision: https://developer.blender.org/D3152
2.8x branch added bContext arg in many places,
pass eval-context instead since its not simple to reason about what
what nested functions do when they can access and change almost anything.
Also use const to prevent unexpected modifications.
This fixes crash loading files with shadows,
since off-screen buffers use a NULL context for rendering.
Note that some little parts of code have been dissabled because eval_ctx
was not available there. This should be resolved once DerivedMesh is
replaced.
This allows to match and transfer data between two meshes with similar shape but complete arbitrary different transform.
Note that the result will be best if the meshes (more precisely, their vertices) are exact copies of each other.
Otherwise, method used can only perform an approximated best match, which means you'll likely get better
results if you 'visually' make them match in 3D space (and use 'Object Transform') instead.
Titles says everything, just two notes:
* We have to actually transfer plain *normals*, not 'compressed' clnors,
so had to add pre/post process to transfer to make the conversions.
* Also added interpolation and advanced copy/mixing to CD_NORMAL, for same reasons.