Blender Git Loki

Added LSCM UV Unwrapping:
http://www.loria.fr/~levy/Galleries/LSCM/index.html
http://www.loria.fr/~levy/Papers/2002/s2002_lscm.pdf

Implementation Least Squares Conformal Maps parameterization, based on
chapter 2 of:
Bruno Levy, Sylvain Petitjean, Nicolas Ray, Jerome Maillot. Least Squares
Conformal Maps for Automatic Texture Atlas Generation. In Siggraph 2002,
July 2002.

Seams: Stored as a flag (ME_SEAM) in the new MEdge struct, these seams define
where a mesh will be cut when executing LSCM unwrapping. Seams can be marked
and cleared in Edit Mode. Ctrl+EKEY will pop up a menu allowing to Clear or Mark
the selected edges as seams.

Select Linked in Face Select Mode now only selects linked faces if no seams
separate them. So if seams are defined, this will now select the 'face group'
defined by the seams. Hotkey is still LKEY.

LSCM Unwrap: unwrap UV's by calculating a conformal mapping (preserving local
angles). Based on seams, the selected faces will be 'cut'. If multiple
'face groups' are selected, they will be unwrapped separately and packed in
the image rectangle in the UV Editor. Packing uses a simple and fast
algorithm, only designed to avoid having overlapping faces.

LSCM can be found in the Unwrap menu (UKEY), and the UV Calculation panel.

Pinning: UV's can be pinned in the UV Editor. When LSCM Unwrap is then
executed, these UV's will stay in place, allowing to tweak the solution.
PKEY and ALT+PKEY will respectively pin and unpin selected UV's.

Face Select Mode Drawing Changes:
- Draw Seams option to enable disable drawing of seams
- Draw Faces option to enable drawing of selected faces in transparent purple
- Draw Hidden Edges option to enable drawing of edges of hidden faces
- Draw Edges option to enable drawing of edges of visible faces

The colors for these seams, faces and edges are themeable.