- drawing face normals was broken (using wrong index).
- drawing flat faces in solid mode would display ugly tesselation normals (as if the model was made of triangles).
- drawing smooth faces in solid mode would show vertex normals based on tesselation (heavily slant in 1 direction).
now the normals are calculated and stored per polygon (will save some memory too for non tri meshes).
possiblem, this has to guess when the size is too big so as to re-
well.
If this isnt done, then the number of faces is used to allocate the
initial array to at least avoid many small allocs.
added BLI_array_reserve() to reserve elements and avoid reallocing many
small arrays when the loop starts.
- made editbmesh_calc_modifiers() ensure tessfaces, this has the advantage that if the tessfaces are already created they wont get re-made as was happening before.
- Pass MFace, MTface and OrigIndex arrays via userData to compareDrawParams callback
rather than looking up for this layers for each face
- This allowed to avoid massing DM to compare callback which seems like a bad-level pass
- Fixed crashes on some video cards when assigning different materials to different
faces in edit mode. Both of intel and nvidia cards in my laptop were affected by
this error
