Blender Git Loki

Fix crashes on undo when workflow has a nodetree.

Still getting memory leaks on exit, they likely occur because main is
owner of nodetree but we should give it to workflow instead.

Workflow shader fixes:

* ID type for GPUWorkflow shaders gets refined correctly
* GPUWorkflow correctly linked to spaceview3d when loading file
* Correct Icons in Node editor
* Creating a node tree works (but it's empty)

WIP new node type for workflow shaders

Workflow shader data

Hook the struct to more places. Now there is a button
to choose a workflow instead of a draw type in the new viewport
(still needs to be somehow sorted according to object mode)

Add workflow shader ID to the system

Only struct definitions here. Workflow is also
set per 3d region. (We should be able to get a
workflow per region just like current textured,
solid etc modes can be set per 3D region)

Add compositing and proper back drawing back to new viewport.

draw grid floor with GPUx API

Single draw call for the default case (grid floor with X and Y axes).

Z axis needs a second draw call because it uses 3D coordinates.

add vec2f convenience function to GPUx

improve grid floor drawing function

Maintain visual hierarchy of the grid:
- emphasized lines draw atop normal lines
- axes draw atop all lines (same as before)

Draw axes only once, not twice.

Return early if nothing to draw.

state tracking API - reorder function args

in order of importance.

Doing this early, before it�??s used in more places.

state tracking API - pass NULL to use defaults

reduces typing needed

new grid floor drawing function

changes:
- use vec2 instead of vec3 for grid
- single glBegin/End for axis lines
- draw axes regardless of grid-line count
- use depth buffer

tweak GL state tracking

New defaults to match common 3D view usage:
- draw both sides (backface culling off)
- depth buffer test & write enabled

Also made default state more readable.
Fixed copy-paste error, GL_POLYGON_STIPPLE.

Mesh objects now draw fine in wireframe and (smooth) solid modes. Now
compatible with UI widgets drawn later!

add runtime check for VAO support

smooth lit meshes

WIP�?� still having some depth buffer issues

draw derived mesh with GPUx API

draw base mesh with GPUx API

Vertex and Edge work great, Face not so much yet �?? totface = 0 so
nothing is drawn. Will work on derived mesh next.

draw_mesh_object_new_new is simplified to draw mesh geometry and
nothing else. Use draw_mesh_object or draw_mesh_object_new for full
functionality.

tweak GPUx draw to use actual max index

instead of max allowed index.

This is a looser restriction than before.

fix compilation when TRUST_NO_ONE is disabled

More changes to defines, add GPUx prefix to public API