Sculpt Face Sets

Face Sets are the new system to control the visibility state of the mesh in sculpt and paint modes. They are designed to work in modes where brushes are the primary way of interaction and they provide much more control when working with meshes with complex shapes and overlapping surfaces.

This initial commit includes:
- Sculpt Face Sets data structures and PBVH rendering.
- Face Set overlay and opacity controls.
- Sculpt Undo support.
- Remesher reprojection support. The visibility state of the mesh is also preserved when remeshing.
- Automasking and Mesh filter support.
- Mask expand operator mode to expand Face Sets (Shift + W) and flood fill areas by connectivity (press Ctrl while expanding).
- Sculpt Mode Face Sets and Visibility API.
- Sculpt Face Sets creation and visibility management operators.
- Operator to randomize the Face Sets colors.
- Draw Face Sets brush tool to create and edit the Face Sets. Drawing on the mesh creates a new Face Set. Pressing Ctrl before drawing modifies the Face Set under the brush at the beginning of the stroke.
- Updated keymap and menu to work with Face Sets from Sculpt Mode (H to toggle visibility, Alt + H to show all, Shit + H to hide).
- Pie menu on the W key with Face common Sets operations.

Know limitations:
- Multires support. The Face Sets and Visibility API needs to be implemented for Multires.

Reviewed By: jbakker, #user_interface, Severin

Differential Revision: https://developer.blender.org/D6070

1 files changed, 5 insertions, 1 deletions

diff --git a/source/blender/gpu/GPU_buffers.h b/source/blender/gpu/GPU_buffers.h
index c4540cc1b1a..f5f7f9ee07c 100644
--- a/source/blender/gpu/GPU_buffers.h
+++ b/source/blender/gpu/GPU_buffers.h
@@ -54,6 +54,7 @@ GPU_PBVH_Buffers *GPU_pbvh_mesh_buffers_build(const int (*face_vert_indices)[3],
                                               const struct MLoopTri *looptri,
                                               const struct MVert *verts,
                                               const int *face_indices,
+                                              const int *sculpt_facemap,
                                               const int face_indices_len,
                                               const struct Mesh *mesh);
 
@@ -70,7 +71,8 @@ void GPU_pbvh_grid_buffers_update_free(GPU_PBVH_Buffers *buffers,
 /* Update mesh buffers without topology changes. Threaded. */
 enum {
   GPU_PBVH_BUFFERS_SHOW_MASK = (1 << 1),
-  GPU_PBVH_BUFFERS_SHOW_VCOL = (1 << 1),
+  GPU_PBVH_BUFFERS_SHOW_VCOL = (1 << 2),
+  GPU_PBVH_BUFFERS_SHOW_SCULPT_FACE_SETS = (1 << 3),
 };
 
 void GPU_pbvh_mesh_buffers_update(GPU_PBVH_Buffers *buffers,
@@ -79,6 +81,8 @@ void GPU_pbvh_mesh_buffers_update(GPU_PBVH_Buffers *buffers,
                                   int totvert,
                                   const float *vmask,
                                   const struct MLoopCol *vcol,
+                                  const int *sculpt_face_sets,
+                                  const int face_sets_color_seed,
                                   const int (*face_vert_indices)[3],
                                   const int update_flags);