Blender Git Loki

Cycles: Add option to split triangle motion primitives by time steps

Similar to the previous commit, the statistics goes as:

BVH Steps Render time (sec) Memory usage (MB)
0 46 260
1 27 373
2 18 598
3 15 826

Scene used for the tests is the agent's body from one of the barber
shop scenes (no textures or anything, just a diffuse material).

Once again this is limited to regular (non-spatial split) BVH,
Support of spatial split to this feature will come later.

Cycles: Add option to split curve motion primitives by time steps

The idea is to create several smaller BVH nodes for each of the motion
curve primitives. This acts as a forced spatial split for the single
primitive.

This gives up render time speedup of motion blurred hair in the cost
of extra memory usage. The numbers goes as:

BVH Steps Render time (sec) Memory usage (MB)
0 258 191
1 123 278
2 69 453
3 43 627

Scene used for the tests is the agent's hair from one of the barber
shop scenes.

Currently it's only limited to scenes without spatial split enabled,
since the spatial split builder requires some changes to work properly
with motion steps coordinates.

Cycles: Add utility function to calculate curve boundbox from given 4 keys

Also fixed some issues with motion keys calculation:

- Clamp lower and upper limits of curves so we can safely call those
functions for the very first and very last curve segment.
- Fixed wrong indexing for the curve radius array.
- Fixed wrong motion attribute offset calculation.

Cycles: Cleanup, trailing whitespace

Cycles: Split motion triangle file once again, avoids annoying forward declarations

Cycles: Move motion triangle intersection functions to own file

Mimics how regular triangles are working and makes it more clear where
the stuff is located in the kernel.

Needed to have some forward declarations because of the current placement
of things in the kernel.

Cycles: Cleanup, better variable name

Cycles: Add utility function to fetch motion keys while on CPU side

Cycles: Cleanup, comments

Cycles: Add utility function to fetch motion triangle when on CPU side

Cycles: Cleanup, delete trailing whitespace

Fix T50460. Greying out issue with Cycles culling options.

Fix T50517: Rendering expecting time is negative

Fix T49857: Blender crashes after adding texture node to compositing tree

FIX T49899: Add EIGEN_MAKE_ALIGNED_OPERATOR_NEW to classes that use eigen's data types , to force aligned on 16 byte boundaries.

Cycles: Fix compilation error on with older GCC

Hopefully it works on all platforms now.

Depsgraph: Use HIGH priority for scheduled tasks

This kind of keeps threads "warmer" and should in theory give better
cache coherency bringing some %% of speedup. It was already tested
few months ago and it gave few % speedup in barber shop, but was
reverted due to some bone popping. The popping is now fixed so it
should be fine to use new scheduling policy.

Depsgraph: Only re-schedule objects which are on visible layers

Otherwise it's possible to cause infinite update loop in Cycles viewport.

Gets a bit messy logic, need to revisit this..

Depsgraph: avoid more transitive relations for rigid body simulation

Depsgraph: Bone parent should also include armature transform relation

It is required to have world-space bone position, which consists of armature
object transform and local bone transform.