Armature "Envelope" editing.

For defining the deformation distances of Bones, three values are being
used now. The bone tip and root radius define the bone-shape itself and the
"dist" defines the soft area around it. A full (user) doc is in CMS here;

http://www.blender3d.org/cms/Armature_Envelopes.647.0.html

Note: todo still is allowing both Vertex Deform Groups and these Envelopes
together (and or per Bone).

Also part of this commit is:

- New: Hiding bones in EditMode. This is a separate 'hide flag', so you can
  keep the PoseMode hidden Bones separate from EditMode.
  (In the future we should do some kind of bone-grouping or so)
- While transform(), the hotkeys G,R,S only switch mode when the previous
  mode was compatible. Caused conflicts with Crease/BoneDist/etc.
- Deleting the last VertexGroup now also deletes the entire Mesh 'dvert'
  data. Sounds logical, but remember that VertexGroups are partial on a
  Mesh, partial on Object. Weird design decision though...
  Anyhoo, at this moment the only way to have Bone Envelopes deform, is
  by deleting all VertexGroups!
- In PoseMode, the hotkey ALT+S now does both B-Bone size or Envelope,
  depending draw type.
- In EditMode, Extrude now also works when only Root points were selected.
- Weight editing is also symmetrical btw, with the "X-axis Mirror" option
  set.

1 files changed, 13 insertions, 3 deletions

diff --git a/source/blender/src/editdeform.c b/source/blender/src/editdeform.c
index f600c8e5537..053151e5c4b 100644
--- a/source/blender/src/editdeform.c
+++ b/source/blender/src/editdeform.c
@@ -193,9 +193,16 @@ void del_defgroup (Object *ob)
 	/* Update the active material index if necessary */
 	if (ob->actdef==BLI_countlist(&ob->defbase))
 		ob->actdef--;
-
+	
 	/* Remove the group */
 	BLI_freelinkN (&ob->defbase, defgroup);
+	
+	/* remove all dverts */
+	if(ob->actdef==0) {
+		Mesh *me= ob->data;
+		free_dverts(me->dvert, me->totvert);
+		me->dvert= NULL;
+	}
 }
 
 void create_dverts(Mesh *me)
@@ -288,8 +295,11 @@ void add_vert_defnr (Object *ob, int def_nr, int vertnum,
 
 	/* get the vert
 	 */
-	dv = ((Mesh*)ob->data)->dvert + vertnum;
-
+	if(((Mesh*)ob->data)->dvert)
+		dv = ((Mesh*)ob->data)->dvert + vertnum;
+	else 
+		return;
+	
 	/* Lets first check to see if this vert is
 	 * already in the weight group -- if so
 	 * lets update it