Armature Modifier: skip non-deforming vertices in Multi-Modifier mode.

The modifier already contained a check to skip complex processing of
vertices that won't produce any deformation due to the vertex group
mask, but this only works for the non-Multi Modifier case. This adds
a similar check for the Multi Modifier mode.

Differential Revision: https://developer.blender.org/D16152

1 files changed, 14 insertions, 4 deletions

diff --git a/source/blender/blenkernel/intern/armature_deform.c b/source/blender/blenkernel/intern/armature_deform.c
index 4acbcbfb13e..89afb886fc2 100644
--- a/source/blender/blenkernel/intern/armature_deform.c
+++ b/source/blender/blenkernel/intern/armature_deform.c
@@ -301,12 +301,22 @@ static void armature_vert_task_with_dvert(const ArmatureUserdata *data,
   }
 
   /* check if there's any  point in calculating for this vert */
-  if (armature_weight == 0.0f) {
-    return;
+  if (vert_coords_prev) {
+    if (prevco_weight == 1.0f) {
+      return;
+    }
+
+    /* get the coord we work on */
+    co = vert_coords_prev[i];
   }
+  else {
+    if (armature_weight == 0.0f) {
+      return;
+    }
 
-  /* get the coord we work on */
-  co = vert_coords_prev ? vert_coords_prev[i] : vert_coords[i];
+    /* get the coord we work on */
+    co = vert_coords[i];
+  }
 
   /* Apply the object's matrix */
   mul_m4_v3(data->premat, co);