Blender Git Loki

Viewport: fix depth not being cleared in ortho mode

Merge remote-tracking branch 'origin/master' into blender2.8

Removed default values in setup functions and added extra functions for
GGX with fresnel.

OpenGL: mesh batch cache (WIP)

Gawain batches are built on demand while drawing, then kept in this per-DerivedMesh cache.

A mesh's batches try to share vertex buffers as much as possible.

Not sure if this file is the best home for this code, but functions in this file are the only users of the cache. So maybe.

Big part of T49165

Cycles: Add missing check for split kernel build error

Switched from uniform to cosine hemisphere sampling for the diffuse and
the sheen part.

Merge branch 'master' into cycles_split_kernel

make View3D depth debug code optional

Quick hack to optionally disable depth buffer debugging at compile time.

Will this be useful for users or just during development?

OpenGL: 3D View background & depth buffer details

Surveying buffer usage & clears for new viewport. Not yet perfect, but closer. Committing from Mac so I can test this on Windows.

Using new matrix API (T49450) for gradient background.

CMake: Followup to previous commit, try to ensure -ldl is always last

Seems CMake will rearrange and copy libraries which are passed to the linker
when some of the libraries is listed twice (for example, -lz from png libraries
and -l for blender itself). This was causing libopenimageio to be added somewhere
at the end of linking flags without -ldl followed after which was causing linking
issues.

Fix possible compilation error with OIIO enabled

OIIO library has plugin API which uses dlopen()/dlclose() so need to
link OIO libraries against dl library.

OpenGL: new built-in shaders for mesh edges

OpenGL: clean up glActiveTexture usage

Removed some of my earlier glActiveTexture calls. After reviewing the
code I now trust that GL_TEXTURE0 is active by default. Fewer GL calls,
same results.

Fixed some misuse of glActiveTexture & glUniformi, mostly my fault.
Caught by --debug-gpu on Windows. Don't know why this appeared to be
working previously!

Plus some easy cleanup nearby.

Viewport: original gradient background

Last but not least, fix the original 3d view background based on
@merwin's comment.

Viewport: move the background to the "modern" viewport

This also leaves room for the gradient background Mike Erwin wants to
implement.

immediate mode: background

There is a problem here, which is that we can't use immediate mode here
until we rely on `GPU_material_bind`.

(cc: @merwin)

Cycles: Add AVX2 path to subsurface triangle intersection

Similar to regular triangle intersection case. Gives about 3% speedup rendering
SSS object on my desktop,

Question: how to avoid such a code duplication in a nice way without speed loss?

Removed the color parameters from the diffuse and sheen shader and use
them as closure weights instead.

Viewport: fix depth filled before solid plates

Cycles: Don't use guarded vector for statically initialized data

This will confuse hell of a guarded allocators because it is possible
to have allocation happened prior to Blender's guarded allocator is
fully initialized.

This was causing crashes and assert failures when running blender
with fully guarded memory allocator.