Blender Git Loki

OpenSubdiv: Add a workaround to prevent crash using OpenGL from non-main thread

Added new eval code (computes first and second surface partials). Still buggy near multi-knots.

OpenSubdiv: Get rid of legacy drawing hacks in opensubdiv_gpu

OpenSubdiv: Initial glue to the GPU_material routines

For now this only tested on matcaps, the rest of GLSL display is
considered unworkable.

This implements ability to define geometry shader for the GPU
material which later is to be used for texture coordinates generation.

For now GOU materials are split depending on thether they're used
for OpenSubdiv mesh display or for "regular" mesh display. In the
future it'll be possible to get rid of such a split, but that'd
require a bit of changes in how this stuff is used all over the
place. better to do it after the viewport refactor project.

And we're now officially only supporting GPU-side tessellation
only for rather modern GPU, supporting older ones becomeng more
and more difficult. If GPU does not support recent GLSL shading
then Blender will fallback to CPU-side grids evaluation, but it
will still happen using OpenSubdiv. So in the future (once we'll
support uniform subdivisions in evlauator API) there'll be no
differences between old and new GPU visualization.

For those who're using older GPU added new compute type in user
preferences which is called NONE. This means CPU-side tessellation
will be used.

removing source duplicates

compiling & linking; unused paths deleted; compile flags for manta removed

depends added, unused list commands removed

non-existing files generated and preprocessed

OpenSubdiv: Use some hacks in order to make it easier to glue with GPU_material

The idea is to use older glsl version (namely 1.3, the same as used for bump
mapping) and require some extensions from newer GLSL in order to use geometry
shader.

This all should make it easier to glue up OpenSubdiv shaders with shaders from
GPU_material.

OpenSubdiv: Cleanup -- no need to use extensions from glsl4 when shader is glsl5

OpenSubdiv: Fix crash when drawing mesh without faces

OpenSubdiv: Reduce number of glDrawEleemnts calls when in solid view

Made it so OsdGLMesh partitions are drawn in batches, so if mesh does have
a continuous set of faces with the same material they all will be displayed
with a single glDrawEelemnts call.

Not sure how this affects on performance on the better quality cards, but
on laptop it brings FPS back to the same value as it was before implementing
multiple textures in solid view (it's around 25% speed gain on Intel card).

That's a good practice anyway to reduce number of glDrawElements anyway, so
even if we wouldn't support low-end GPU with old driver (because of geometry
shader) it's still good to have.

Improvements to textured and GLSL display will be done later,

paths for repositioned manta_pp folder correct

removing repository info

fixed prep-not-found issue,files compiling

OpenSubdiv: Simplify code around wireframe mittion

OpenSubdiv: Reduce number of glGet* per mesh drawing

This also reduces number of inverse matrix calculation by
updating light model and transformation matricies once per
mesh drawing.

OpenSubdiv: Dedublicate a bit of a code

Merge branch 'master' into opensubdiv-modifier

Use size for fixed length array args