This includes much improved GPU rendering performance, viewport interactivity,
new shadow catcher, revamped sampling settings, subsurface scattering anisotropy,
new GPU volume sampling, improved PMJ sampling pattern, and more.
Some features have also been removed or changed, breaking backwards compatibility.
Including the removal of the OpenCL backend, for which alternatives are under
development.
Release notes and code docs:
https://wiki.blender.org/wiki/Reference/Release_Notes/3.0/Cycleshttps://wiki.blender.org/wiki/Source/Render/Cycles
Credits:
* Sergey Sharybin
* Brecht Van Lommel
* Patrick Mours (OptiX backend)
* Christophe Hery (subsurface scattering anisotropy)
* William Leeson (PMJ sampling pattern)
* Alaska (various fixes and tweaks)
* Thomas Dinges (various fixes)
For the full commit history, see the cycles-x branch. This squashes together
all the changes since intermediate changes would often fail building or tests.
Ref T87839, T87837, T87836
Fixes T90734, T89353, T80267, T80267, T77185, T69800
This adds compaction support for OptiX acceleration structures, which reduces the device memory footprint in a post step after building. Depending on the scene this can reduce the amount of used device memory quite a bit and even improve performance (smaller acceleration structure improves cache usage). It's only enabled for background renders to make acceleration structure builds fast in viewport.
Also fixes a bug in the memory management for OptiX acceleration structures: These were held in a dynamic vector of 'device_memory' instances and used the mem_alloc/mem_free functions. However, those keep track of memory instances in the 'cuda_mem_map' via pointers to 'device_memory' (which works fine everywhere else since those are never copied/moved). But in the case of the vector, it may decide to reallocate at some point, which invalidates those pointers and would result in some nasty accesses to invalid memory. So it is not actually safe to move a 'device_memory' object and therefore this removes the move operator overloads again.
Reviewed By: brecht
Differential Revision: https://developer.blender.org/D6369
The algorithm averages normals from nearby surfaces. It uses the same
sampling strategy as BSSRDFs, casting rays along the normal and two
orthogonal axes, and combining the samples with MIS.
The main concern here is that we are introducing raytracing inside
shader evaluation, which could be quite bad for GPU performance and
stack memory usage. In practice it doesn't seem so bad though.
Note that using this feature can easily slow down renders 20%, and
that if you care about performance then it's better to use a bevel
modifier. Mainly this is useful for baking, and for cases where the
mesh topology makes it difficult for the bevel modifier to work well.
Differential Revision: https://developer.blender.org/D2803
