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
This causes some difference in the classroom scene, where ray visibility
tricks are used and break the MIS balance. Otherwise there doesn't seem
to be much effect, but better to use the right formulas. Problem originally
identified by Lukas.
With a Titan Xp, reduces path trace local memory from 1092MB to 840MB.
Benchmark performance was within 1% with both RX 480 and Titan Xp.
Original patch was implemented by Sergey.
Differential Revision: https://developer.blender.org/D2249
This is a prequisite for getting host memory allocation to work. There appears
to be no support for 3D textures using host memory. The original version of
this code was written by Stefan Werner for D2056.
Some drivers may report very large allocation sizes, which could cause
unnecessary memory usage. This is now limited to 2gb which should
still be enough to get the needed performance benefits without waste.
The idea is to make it possible to report extra meta data from
render engine to the file writing. This way we can provide
additional information such as number of samples rendered by
resumable Cycles rendering so we can easily combine files back.
Currently only report number of samples from Cycles when rendering
a single render-layer scene. This is something what was required
here at the studio. We can easily extend that further.
Ideally we would also need to support non-string metadata, but
that's for later.
Reviewers: mont29, campbellbarton
Reviewed By: mont29, campbellbarton
Subscribers: sybren, candreacchio
Differential Revision: https://developer.blender.org/D2502
We are already using the AO distance, so might as well offer this extra
control over the intensity. Useful when an interior scene is supposed to
be significantly darker than the background shader.
