Blender Git Loki

Refactoring: Renamed the "StrandRoot" arrays to "StrandFiber" for clarity.

The strand system contains 2 levels of curve geometry:
- "Strands" are the abstract control strands, editable by the user and thus few in number.
- "Fibers" are renderable curves, generated based on those strands.

"Roots" now is used exclusively for hair follicles, which are attached to
the scalp mesh, i.e. follow the mesh deformation.

Enable render strand display during hair edit mode.

Store a copy of the strand roots array in the strand edit data.

This will allow the edit mode to display render strands as well.
The roots may later be re-scattered or otherwise modified during editing,
and are eventually copied back to the Strands data when applying edits.

Clear the edit draw data on updates, to make edit mode changes visible.

GPU buffer functions for drawing a strand edit BMesh.

Now the object mode and edit mode for strands use the same drawing code.
Derived render strands are not yet supported (they may need re-scattering
during editing) and the tool settings have no effect yet.

Renamed BMesh strand functions to replace deprecated particle term 'keys' by 'vertex'.

Do strand and editstrand drawing in the same place, so they are not shown both.

Support for the Strand data structure in the hair editmode.

Merge branch 'strand_editmode' into strand_gpu_editmode

Merge branch 'master' into strand_gpu

Merge branch 'master' into strand_editmode

Use consistent checks for valid attribute index.

Argument for enabling integer buffers when setting attributes.

Mesh attributes seem to be using float buffers for everything.

Removed the deprecated curve-loop shader variant.

Removed debug shader code.

Working interpolation code for strands.

Various fixes for GL state and some basic texture lookups in the strand geometry shader.

Fix for integer attribute uploading in gpu code.

OpenGL has a separate function for integer attribute pointers.
If the float attribute version is used, the attribute data will be
interpreted and floats and converted to integer values, which
garbles the content of any true int/uint buffer.

Increase soft limit for control strand number for testing.

Use an additional texture buffer for storing curve indices.

The geometry shader will need to do 2 texture lookups per control,
first for getting the control curve start and length, then for
reading the appropriate curve vertices.