Fix bones moving when changing between editmode and posemode.

Patch #25901 by Tobias Oelgarte.

Bone transformations would be converted back and forth between different
representations when changing modes, which due to numerical errors could
lead to bone transformations slowly changing as you edit the armature.

Now the editmode head, tail and roll values are stored in bones and used
directly when entering edit mode. Head and tail were already there but
now we ensure they are the exact same value, roll was not yet there, so
we have a version patch for it.

The sub version was incremented to 1 for the version patch.

1 files changed, 3 insertions, 2 deletions

diff --git a/source/blender/makesdna/DNA_armature_types.h b/source/blender/makesdna/DNA_armature_types.h
index 108c0883f15..89c2d69b8be 100644
--- a/source/blender/makesdna/DNA_armature_types.h
+++ b/source/blender/makesdna/DNA_armature_types.h
@@ -57,8 +57,9 @@ typedef struct Bone {
 	int				flag;
 	
 	float			arm_head[3];		
-	float			arm_tail[3];	/*	head/tail and roll in Armature Space (rest pos) */
+	float			arm_tail[3];	/*	head/tail in Armature Space (rest pos) */
 	float			arm_mat[4][4];  /*  matrix: (bonemat(b)+head(b))*arm_mat(b-1), rest pos*/
+	float           arm_roll;        /* roll in Armature Space (rest pos) */
 	
 	float			dist, weight;			/*  dist, weight: for non-deformgroup deforms */
 	float			xwidth, length, zwidth;	/*  width: for block bones. keep in this order, transform! */
@@ -68,7 +69,7 @@ typedef struct Bone {
 	float			size[3];		/*  patch for upward compat, UNUSED! */
 	int				layer;			/* layers that bone appears on */
 	short			segments;		/*  for B-bones */
-	short 			pad[3];
+	short 			pad[1];
 } Bone;
 
 typedef struct bArmature {