This now supports multiple steps and subframe sampling of motion.
There is one difference for object and camera transform motion blur. It still
only supports two steps there, but the transforms are now sampled at subframe
times instead of the previous and next frame and then interpolated/extrapolated.
This will give different render results in some cases but it's more accurate.
Part of the code is from the summer of code project by Gavin Howard, but it has
been significantly rewritten and extended.
This does not support staying fixed while the surface deforms, but for static
meshes it should match up with the surface texture coordinates. Implemented
as a matrix transform from objects space to mesh texture space.
Making this work for deforming surfaces would be quite complicated, you might
need something like harmonic coordinates as used in the mesh deform modifier,
probably will not be possible anytime soon.
Not the most memory efficient way to store these things but it's simple and
implementing it better requires some work to natively support subd grids as
a primitive in some way.
- Removed the cycles subdivision and interpolation of hairkeys.
- Removed the parent settings.
- Removed all of the advanced settings and presets.
- This simplifies the UI to a few settings for the primitive type and a shape mode.
should be no functional changes yet. UV, tangent and intercept are now stored
as attributes, with the intention to add more like multiple uv's, vertex
colors, generated coordinates and motion vectors later.
Things got a bit messy due to having both triangle and curve data in the same
mesh data structure, which also gives us two sets of attributes. This will get
cleaned up when we split the mesh class.
It's using the Ward BSDF currently, which has some energy loss so might be a bit
dark. More/better BSDF options can be implemented later.
Patch by Mike Farnsworth, some modifications by me. Currently it's not possible yet
to set a custom tangent, that will follow as part of per-bsdf normals patch.
Most of the changes are related to adding support for motion data throughout
the code. There's some code for actual camera/object motion blur raytracing
but it's unfinished (it badly slows down the raytracing kernel even when the
option is turned off), so that code it disabled still.
Motion vector export from Blender tries to avoid computing derived meshes
when the mesh does not have a deforming modifier, and it also won't store
motion vectors for every vertex if only the object or camera is moving.