Matcap support in 3D Viewport.

Full log is here:
http://wiki.blender.org/index.php/Dev:Ref/Release_Notes/2.66/Usability#Matcap_in_3D_viewport

Implementation notes:

- Matcaps are an extension of Solid draw mode, and don't show in other drawmodes.
  (It's mostly intended to aid modeling/sculpt)

- By design, Matcaps are a UI feature, and only stored locally for the UI itself, and
  won't affect rendering or materials.

- Currently a set of 16 (GPL licensed) Matcaps have been compiled into Blender. 
  It doesn't take memory or cpu time, until you use it.

- Brush Icons and Matcaps use same code now, and only get generated/allocated on
  actually using it (instead of on startup).

- The current set might get new or different images still, based on user feedback.

- Matcap images are 512x512 pixels, so each image takes 1 Mb memory. Unused matcaps get 
  freed immediately. The Matcap icon previews (128x128 pixels) stay in memory.

- Loading own matcap image files will be added later. That needs design and code work 
  to get it stable and memory-friendly.

- The GLSL code uses the ID PreviewImage for matcaps. I tested it using the existing
  Material previews, which has its limits... especially for textured previews the
  normal-mapped matcap won't look good.

1 files changed, 3 insertions, 0 deletions

diff --git a/source/blender/editors/include/UI_interface_icons.h b/source/blender/editors/include/UI_interface_icons.h
index f578d68b852..10026bbd50f 100644
--- a/source/blender/editors/include/UI_interface_icons.h
+++ b/source/blender/editors/include/UI_interface_icons.h
@@ -39,6 +39,7 @@ struct World;
 struct Tex;
 struct Lamp;
 struct Material;
+struct PreviewImage;
 struct PointerRNA;
 
 typedef struct IconFile {
@@ -76,6 +77,8 @@ void UI_icons_free_drawinfo(void *drawinfo);
 struct ListBase *UI_iconfile_list(void);
 int UI_iconfile_get_index(const char *filename);
 
+struct PreviewImage *UI_icon_to_preview(int icon_id);
+
 int UI_rnaptr_icon_get(struct bContext *C, struct PointerRNA *ptr, int rnaicon, int big);
 
 #endif /*  __UI_INTERFACE_ICONS_H__ */