Armature: add automatic B-Bone Scale toggles.

Currently B-Bone scaling can only be controlled via their
properties, thus requiring up to 8 drivers per joint between
B-Bones to transfer scaling factors from the handle bone.

A Scale Easing option is added to multiply the easing value
by the Y scale channels to synchronize them - this produces a
natural scaling effect where both the shape of the curve and
the scale is affected.

In addition, four toggles are added for each handle, which
multiply each of the X, Y, Z and Ease values by the matching
Local Scale channel of the handle bone, thus replacing trivial
drivers. The Scale Easing option has no effect on this process
since it's easy to just enable both Length and Ease buttons.

Differential Revision: https://developer.blender.org/D9870

1 files changed, 17 insertions, 0 deletions

diff --git a/source/blender/makesdna/DNA_armature_types.h b/source/blender/makesdna/DNA_armature_types.h
index f5574b36602..3d83d0d2f6f 100644
--- a/source/blender/makesdna/DNA_armature_types.h
+++ b/source/blender/makesdna/DNA_armature_types.h
@@ -302,8 +302,25 @@ typedef enum eBone_BBoneHandleType {
 typedef enum eBone_BBoneFlag {
   /** Add the parent Out roll to the In roll. */
   BBONE_ADD_PARENT_END_ROLL = (1 << 0),
+  /** Multiply B-Bone easing values with Scale Length. */
+  BBONE_SCALE_EASING = (1 << 1),
 } eBone_BBoneFlag;
 
+/* bone->bbone_prev/next_flag */
+typedef enum eBone_BBoneHandleFlag {
+  /** Use handle bone scaling for scale X. */
+  BBONE_HANDLE_SCALE_X = (1 << 0),
+  /** Use handle bone scaling for scale Y (length). */
+  BBONE_HANDLE_SCALE_Y = (1 << 1),
+  /** Use handle bone scaling for scale Z. */
+  BBONE_HANDLE_SCALE_Z = (1 << 2),
+  /** Use handle bone scaling for easing. */
+  BBONE_HANDLE_SCALE_EASE = (1 << 3),
+  /** Is handle scale required? */
+  BBONE_HANDLE_SCALE_ANY = BBONE_HANDLE_SCALE_X | BBONE_HANDLE_SCALE_Y | BBONE_HANDLE_SCALE_Z |
+                           BBONE_HANDLE_SCALE_EASE,
+} eBone_BBoneHandleFlag;
+
 #define MAXBONENAME 64
 
 #ifdef __cplusplus