Blender Git Loki

Cycles: OpenCL split kernel refactor

This does a few things at once:

- Refactors host side split kernel logic into a new device
agnostic class `DeviceSplitKernel`.
- Removes tile splitting, a new work pool implementation takes its place and
allows as many threads as will fit in memory regardless of tile size, which
can give performance gains.
- Refactors split state buffers into one buffer, as well as reduces the
number of arguments passed to kernels. Means there's less code to deal
with overall.
- Moves kernel logic out of OpenCL kernel files so they can later be used by
other device types.
- Replaced OpenCL specific APIs with new generic versions
- Tiles can now be seen updating during rendering

Blender 2.78c: Fix Brick Texture GLSL, broken after Mortar Smooth addition.

Merge branch 'master' into cycles_split_kernel

Cycles: Add OpenCL kernel for zeroing memory buffers

Transferring memory to the device was very slow and there's really no
need when only zeroing a buffer.

Cycles: Add more atomic operations

Cycles: Expose passes size to device tasks

This is needed so devices can know the size of a tile buffer before any
tiles are acquired.

Cycles: Allow device_memory to be used directly

This is useful for when theres no host side memory attched to the buffer

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

OpenGl immediate mode: fix false positive (again)

OpenGL: Fix Object Axes color

OpenGl immediate mode: Fix false positive

OpenGl immediate mode: screen_draw.c

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

Fix Cycles still saving render output when error happened

This was fixed ages ago for the interface case but not for the
command line. The thing here is that currently external engines
are relying on reports system to indicate that error happened
so suppressing reports storage in the background mode prevented
render pipeline from detecting errors happened.

This is all weak and i don't like it, but this is better than
delivering black frames from the farm.

Clay Engine: Started Armature drawing

This should give the overall direction to whom wants to finish it.

- Renamed EDIT mode engine to EDIT_MESH mode engine
- Introduce EDIT_ARMATURE mode engine
- Started to port legacy drawarmature.c to draw_armature.c

Cycles: Get passes size in more robust way

Clay Engine: Renaming shader.

Clay Engine: Prepare for Armature drawing.

- Added runtime display matrices to EditBone and bPoseChannel
- Added Object space instance vertex shader and modified the simple lighting shader accordingly