[Bf-gamedev] New loop normals/tspace needs testing

[Bastien Montagne]

Hi guys,

I (hopefully) mostly finished first step in loop normals work. Now, all 
objects have the option to enable loop normals (with an optional angle 
threshold above which edges are always sharp). Once enabled, final 
derived meshes (structs representing objects to draw or render) gets a 
normal CD layer for their loops (and a tessellated version for its 
tfaces as well). Those loop normals allow to represent flat faces and 
sharp edges. As a temp UI, I added loop normals and angle options in the 
"Item" panel, "Properties" of the 3DView.

Code can be checked out from my svn branch, 
https://svn.blender.org/svnroot/bf-blender/branches/vgroup_modifiers

These data are used in OpenGL preview (only when "VBO" option is 
enabled, for now, I prefer to modify viewport code as few as possible 
currently!), and for tangent space compute as well (note that for this 
one, I assumed it is only used over final dm, this may not be always 
true, have to check this yet). These are also the same as exported in 
OBJ and FBX.

Only remaining TODO for this first step is to export TSpace in FBX (btw, 
if someone could provide me one or two simple ASCII FBX files with 
TSpace data, would be nice ;) ) - and of course, to test!

I hope the core algo to compute loop (split) normals is now OK (I fixed 
two bugs here recently :/ ), but esp. tspace/loopnormals combinations 
are to be checked carefully (baking)…

Cheers,
Bastien