Add cloth pressure vertex group and unlock cloth shrink values range

Introduced a way to specify cloth pressure force influence with a vertex
group. This will allow users to only have pressure affect certain parts
of the mesh.

In addition to this, the "shrink factor" is now also unlocked to allow
negative values and thus allowing the cloth mesh to grow as well.

Reviewed By: Jaques Lucke

Differential Revision: http://developer.blender.org/D6347

1 files changed, 6 insertions, 3 deletions

diff --git a/source/blender/makesdna/DNA_cloth_types.h b/source/blender/makesdna/DNA_cloth_types.h
index 5653e8a0450..aca29fe1bdd 100644
--- a/source/blender/makesdna/DNA_cloth_types.h
+++ b/source/blender/makesdna/DNA_cloth_types.h
@@ -93,9 +93,11 @@ typedef struct ClothSimSettings {
   float collider_friction;
   /** Damp the velocity to speed up getting to the resting position. */
   float vel_damping DNA_DEPRECATED;
-  /** Min amount to shrink cloth by 0.0f (no shrink) - 1.0f (shrink to nothing). */
+  /** Min amount to shrink cloth by 0.0f (no shrink), 1.0f (shrink to nothing), -1.0f (double the
+   * edge length). */
   float shrink_min;
-  /** Max amount to shrink cloth by 0.0f (no shrink) - 1.0f (shrink to nothing). */
+  /** Max amount to shrink cloth by 0.0f (no shrink), 1.0f (shrink to nothing), -1.0f (double the
+   * edge length). */
   float shrink_max;
 
   /* Air pressure */
@@ -107,7 +109,8 @@ typedef struct ClothSimSettings {
      pressure=( (current_volume/target_volume) - 1 + uniform_pressure_force) *
      pressure_factor */
   float pressure_factor;
-  char _pad7[4];
+  short vgroup_pressure;
+  char _pad7[2];
 
   /* XXX various hair stuff
    * should really be separate, this struct is a horrible mess already