Blender Git Commits

Fix T50550: GPUShader: compile error - Background image not showing in
viewport.

Caused by rBd6cf28c5e15739f864fbf04614c2a50708b4b152, which forgot to
update the GLSL code for the "Light Path" node.

Blender 2.78c: Fix wrong cycles hair render results when using BVH motion steps

This commit contains all commits required to get proper hair rendering
with BVH motion steps enabled.

The issue here was mainly coming from minimal pixel width feature
which is quite commonly enabled in production shots.

This feature will use some probabilistic heuristic in the curve
intersection function to check whether we need to return intersection
or not. This probability is calculated for every intersection check.
Now, when we use multiple BVH nodes for curve primitives we increase
probability of that primitive to be considered a good intersection
for us. This is similar to increasing minimal width of curve.

What is worst here is that change in the intersection probability
fully depends on exact layout of BVH, meaning probability might
change differently depending on a view angle, the way how builder
binned the primitives and such. This makes it impossible to do
simple check like dividing probability by number of BVH steps.

Other solution might have been to split BVH into fully independent
trees, but that will increase memory usage of all the static
objects in the scenes, which is also not something desirable.

For now used most simple but robust approach: store BVH primitives
time and test it in curve intersection functions. This solves the
regression, but has two downsides:

- Uses more memory.

which isn't surprising, and ANY solution to this problem will
use more memory.

What we still have to do is to avoid this memory increase for
cases when we don't use BVH motion steps.

- Reduces number of maximum available textures on pre-kepler cards.

There is not much we can do here, hardware gets old but we need
to move forward on more modern hardware..

Blender 2.78c: Port all commits related on new Cycles regression tests

Cycles: Round global size down rather than up to avoid setting too large

Cycles: Get passes size in more robust way

Cycles: Use correct index for sd_dl_shadow after removing ccl_fetch

Revert "Cycles: Faster version of driver workaround for OpenCL"

Was getting infrequent hangs, unfortunately we have to take the performance
hit of clFinish for now.

This reverts commit 122743e7f23f8df908bcd10322d39f951ebc83e2.

Cycles: Fix buffer offsets in split kernel

Was getting wrong renders with multiple devices.

Cycles: Remove ccl_fetch and SOA

Cycles: Remove all split kernel stuff from opencl.h

Cycles: Reenable debug tile size for viewport rendering

Not a problem now that split kernel global size is decoupled from tile size.

manta script cleanup

Cycles: Report device maximum allocation and detected global size

updated manta vec3 extrapolation

now using inside mode as well - similar to extrapolateLsSimple()

updated mesh distance function

now using raycast in inverted direction as well. if this is not done, there are cases with wrong phi grid (swapped inside and outside)

Cycles: Update tiles less frequently for split kernel

Increases the time between tile updates exponentially until theres 10 seconds
between updates. By having more time between updates we can push more samples
to the device at once and keep the number of threads doing actual work
higher. This gives a nice speed up.

Cycles: Add changes that somehow got left out of previous commit

Cycles: Remove remnants of tile splitting

Cycles: Faster version of driver workaround for OpenCL

Fix typo and change `.enabled` to `.active`