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, 20 insertions, 0 deletions

diff --git a/source/blender/makesrna/intern/rna_brush.c b/source/blender/makesrna/intern/rna_brush.c
index cc39a5dbe8d..fa48cf2f399 100644
--- a/source/blender/makesrna/intern/rna_brush.c
+++ b/source/blender/makesrna/intern/rna_brush.c
@@ -1979,6 +1979,20 @@ static void rna_def_brush(BlenderRNA *brna)
       {0, NULL, 0, NULL, NULL},
   };
 
+  static const EnumPropertyItem brush_deformation_target_items[] = {
+      {BRUSH_DEFORM_TARGET_GEOMETRY,
+       "GEOMETRY",
+       0,
+       "Geometry",
+       "Brush deformation displaces the vertices of the mesh"},
+      {BRUSH_DEFORM_TARGET_CLOTH_SIM,
+       "CLOTH_SIM",
+       0,
+       "Cloth Simulation",
+       "Brush deforms the mesh by deforming the constraints of a cloth simulation"},
+      {0, NULL, 0, NULL, NULL},
+  };
+
   static const EnumPropertyItem brush_elastic_deform_type_items[] = {
       {BRUSH_ELASTIC_DEFORM_GRAB, "GRAB", 0, "Grab", ""},
       {BRUSH_ELASTIC_DEFORM_GRAB_BISCALE, "GRAB_BISCALE", 0, "Bi-scale Grab", ""},
@@ -2207,6 +2221,12 @@ static void rna_def_brush(BlenderRNA *brna)
   RNA_def_property_ui_text(prop, "Curve Preset", "");
   RNA_def_property_update(prop, 0, "rna_Brush_update");
 
+  prop = RNA_def_property(srna, "deform_target", PROP_ENUM, PROP_NONE);
+  RNA_def_property_enum_items(prop, brush_deformation_target_items);
+  RNA_def_property_ui_text(
+      prop, "Deformation Target", "How the deformation of the brush will affect the object");
+  RNA_def_property_update(prop, 0, "rna_Brush_update");
+
   prop = RNA_def_property(srna, "elastic_deform_type", PROP_ENUM, PROP_NONE);
   RNA_def_property_enum_items(prop, brush_elastic_deform_type_items);
   RNA_def_property_ui_text(prop, "Deformation", "Deformation type that is used in the brush");