Sculpt: Enable Cloth Simulation Target for Pose and Boundary

This adds a new brush property called "Deformation Target" which
controls how the brush deformations is going to affect the mesh data. By
default is set to Geometry, which makes the brushes displace the
vertices. When set to Cloth Simulation, the deformation of the brush is
applied to the cloth solver constraints, so the simulation is
responsible to apply the final deformation. This allows to add cloth
simulation effects to other sculpt tools with minor modifications to their
code.

This patch enables Cloth Simulation deformation target for Pose and
Boundary brushes, which are tools that are already designed to work in
low poly counts and produce large deformations. This allows creating the
most common cloth effects, like bending and compressing folds, without
relying on collisions.

Reviewed By: sergey

Differential Revision: https://developer.blender.org/D8578

1 files changed, 8 insertions, 1 deletions

diff --git a/source/blender/makesdna/DNA_brush_types.h b/source/blender/makesdna/DNA_brush_types.h
index 6c4d2856526..3873763e3e0 100644
--- a/source/blender/makesdna/DNA_brush_types.h
+++ b/source/blender/makesdna/DNA_brush_types.h
@@ -322,6 +322,11 @@ typedef enum eBrushCurvePreset {
   BRUSH_CURVE_SMOOTHER = 9,
 } eBrushCurvePreset;
 
+typedef enum eBrushDeformTarget {
+  BRUSH_DEFORM_TARGET_GEOMETRY = 0,
+  BRUSH_DEFORM_TARGET_CLOTH_SIM = 1,
+} eBrushDeformTarget;
+
 typedef enum eBrushElasticDeformType {
   BRUSH_ELASTIC_DEFORM_GRAB = 0,
   BRUSH_ELASTIC_DEFORM_GRAB_BISCALE = 1,
@@ -539,7 +544,7 @@ typedef struct Brush {
   /** Source for fill tool color gradient application. */
   char gradient_fill_mode;
 
-  char _pad0[1];
+  char _pad0[5];
 
   /** Projection shape (sphere, circle). */
   char falloff_shape;
@@ -587,6 +592,8 @@ typedef struct Brush {
   /* Maximun distance to search fake neighbors from a vertex. */
   float disconnected_distance_max;
 
+  int deform_target;
+
   /* automasking */
   int automasking_flags;
   int automasking_boundary_edges_propagation_steps;