Pataz-Gooseberry Request: Limits on Volume Preservation for Spline IK

This commit adds a new type of volume preservation mode to Spline IK
which makes it possible to set limits on the minimum and maximum
scaling of bone "fatness".

* The old volume preseving mode has been kept but renamed, to avoid
  breaking old rigs. "Volume Presevation" uses the new method, while
  "Inverse Preservation" is the old one.

* The code and settings for this new xz scale mode are directly lifted
  from the improved Stretch To constraint

1 files changed, 19 insertions, 1 deletions

diff --git a/release/scripts/startup/bl_ui/properties_constraint.py b/release/scripts/startup/bl_ui/properties_constraint.py
index e6b62cae6ef..0c5aae1de2f 100644
--- a/release/scripts/startup/bl_ui/properties_constraint.py
+++ b/release/scripts/startup/bl_ui/properties_constraint.py
@@ -768,9 +768,27 @@ class ConstraintButtonsPanel():
         col = layout.column()
         col.label(text="Chain Scaling:")
         col.prop(con, "use_y_stretch")
-        col.prop(con, "xz_scale_mode")
         col.prop(con, "use_curve_radius")
 
+        layout.prop(con, "xz_scale_mode")
+
+        if con.xz_scale_mode == 'VOLUME_PRESERVE':
+            layout.prop(con, "bulge", text="Volume Variation")
+            split = layout.split()
+            col = split.column(align=True)
+            col.prop(con, "use_bulge_min", text="Volume Min")
+            sub = col.column()
+            sub.active = con.use_bulge_min
+            sub.prop(con, "bulge_min", text="")
+            col = split.column(align=True)
+            col.prop(con, "use_bulge_max", text="Volume Max")
+            sub = col.column()
+            sub.active = con.use_bulge_max
+            sub.prop(con, "bulge_max", text="")
+            col = layout.column()
+            col.active = con.use_bulge_min or con.use_bulge_max
+            col.prop(con, "bulge_smooth", text="Smooth")
+
     def PIVOT(self, context, layout, con):
         self.target_template(layout, con)