Blender Git Loki

Cycles: Fix wrong original ray used for SSS baking

Also de-duplicated some code by moving to an utility function.

Cycles: Set of fixes for delayed SSS ray tracing

There were multiple issues which are solved now:

- It was possible that ray wouldn't be bounced off the BSSRDF, for example
when PDF or shader eval is zero. In this case PathState might have been
left in pre-bounced state which would have been gave incorrect shading
results.

This is solved by having separate PathState for each of the hits.

- Path radiance summing wasn't happening correct as well, indirect rays
were using wrong path radiance in the case when there were more than
one hit recorded.

This is now using a bit trickier state machine which calculates path
radiance for just SSS (both direct and indirect) and then sums it back
to the final radiance.

- Previous commit wasn't totally correct either and was an induced bug
due to wrong path state left from the "un-happened" ray bounce.

There should be no special case happening here, BSSRDFs will be replaced
with diffuse ones due to PATH_RAY_DIFFUSE_ANCESTOR flag.

- Merged back codebases for "delayed" and "immediate" indirect SSS ray
tracing, hopefully making it easier to maintain the codebase.

Sure this changes brings memory usage back by about 4-5%, but overall
it's still about 2x memory reduction for the experimental kernel here.

Thanks Brecht for the review!

Cycles: Fallback to diffuse BSDF for the indirect SSS rays when BSSRDF is hit

This is actually how it was intended to work, just didn't notice it wasn't
really happening in the main ray loop.

Solves some memory issues reported in T46880.

Cycles: Fix missing indirect subsurface initialization in the bake code

OpenGL: remove unnecessarily paranoid bound texture preservation.

OpenGL: assume GL_TEXTURE_ENV_MODE GL_MODULATE is the default state.

OpenGL: set OpenGL lights through simple shader API.

OpenGL: update simple shader API.

Restore fixed function lighting code for now and control use of GLSL shader
with a variable, make light types more clear, reduce state changes, some other
minor tweaks.

OpenGL: rename GPU_enable_material to better indicate it's binding shaders.

Fix a regression introduced by https://developer.blender.org/D1396 on video playing

Fix a regression introduced by https://developer.blender.org/D1396 on video playing

Look at @mariomey example file.

Reviewers: panzergame

Subscribers: mariomey

Projects: #game_engine

Differential Revision: https://developer.blender.org/D1623

Fix possible hang on buffer allocation failure. Reported by coverity
scan, thanks...errr.

BMesh: pass loops instead of edges/verts to filter funcs

This allows to check the source face we're walking over.

BMesh: use typed filter callbacks (const args too)

OpenGL: fix cycles texture draw mode not respecting double sided lighting.

Fix T46883: VSE Meta Strip crash on leaving Meta editing (tab).

Own stupid copy/paste error in recent commit.

Fix T46827: Appending Specific Groups Doesn't Work on Windows.

Issue was with datablocks which names would include '/', new filebrowser filelisting code
would cleanup the entire filepath, hence giving invalid filename in this case.

That 'path separator in ID names' bit us already in lib/datatype/datablock separating func,
this is really stupid to allow that in something handled as a filepath imho, but well...

Note: would have break the same under *nix with '' char.

Fix (unreported) broken BLI_join_dirfile() in some cases on Windows.

That function was epic failing in case trying to join '//' and 'foo.blend', would
give '//foo.blend'... Now check for both SEP and ALTSEP!

fix T46868: added workaround for a collada issue with UTF8 filenames

Cycles: Fully roll-back to non-delayed SSS indirect rays for CPU

There are some issues to be solved with the recent optimization we did for
the indirect rays for the SSS. Those issues will take a bit of a time to
be fully solved still and we need to unlock Caminandes team now, so let's
revert some changes back.

CUDA will still use delayed indirect rays since it's an experimental
feature.

For the details about what's to be done still please refer to T46880.

Revert "Cycles: Fix wrong SSS with regular path tracing and clamping enabled"

This wasn't really a complete fix and only worked if there was a single scatter
event recorded only. Proper fix requires some more thoughts to make it correct
without memory use increase.

This reverts commit bf9e88bfbebaf5c6228363560970fa526e779c8b.