Blender Git Loki

Edit Mesh: Optimize the overlay triangle geometry shader

On my test it's 30% faster than before.

Test case : Suzanne, subsurf lvl3, 64K tris, Edge select mode for fair
comparison.

0.95ms before optimization
0.64ms after optimization

Note that this only optimize the "nicest" display of edit mesh overlays,
not the one when rotating the view where half of the border edges are
missing.