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, 11 insertions, 6 deletions

diff --git a/source/blender/blenkernel/intern/customdata.c b/source/blender/blenkernel/intern/customdata.c
index 93db44ce60a..33707d3f18d 100644
--- a/source/blender/blenkernel/intern/customdata.c
+++ b/source/blender/blenkernel/intern/customdata.c
@@ -1621,6 +1621,8 @@ static const LayerTypeInfo LAYERTYPEINFO[CD_NUMTYPES] = {
     {sizeof(short[4][3]), "", 0, NULL, NULL, NULL, NULL, layerSwap_flnor, NULL},
     /* 41: CD_CUSTOMLOOPNORMAL */
     {sizeof(short[2]), "vec2s", 1, NULL, NULL, NULL, NULL, NULL, NULL},
+    /* 42: CD_SCULPT_FACE_SETS */
+    {sizeof(int), "", 0, NULL, NULL, NULL, NULL, NULL, NULL},
 };
 
 static const char *LAYERTYPENAMES[CD_NUMTYPES] = {
@@ -1668,6 +1670,7 @@ static const char *LAYERTYPENAMES[CD_NUMTYPES] = {
     /* 39-41 */ "CDMLoopTangent",
     "CDTessLoopNormal",
     "CDCustomLoopNormal",
+    "CDSculptFaceGroups",
 };
 
 const CustomData_MeshMasks CD_MASK_BAREMESH = {
@@ -1692,7 +1695,7 @@ const CustomData_MeshMasks CD_MASK_MESH = {
     .lmask = (CD_MASK_MLOOP | CD_MASK_MDISPS | CD_MASK_MLOOPUV | CD_MASK_MLOOPCOL |
               CD_MASK_CUSTOMLOOPNORMAL | CD_MASK_GRID_PAINT_MASK | CD_MASK_GENERIC_DATA),
     .pmask = (CD_MASK_MPOLY | CD_MASK_RECAST | CD_MASK_FACEMAP | CD_MASK_FREESTYLE_FACE |
-              CD_MASK_GENERIC_DATA),
+              CD_MASK_GENERIC_DATA | CD_MASK_SCULPT_FACE_SETS),
 };
 const CustomData_MeshMasks CD_MASK_EDITMESH = {
     .vmask = (CD_MASK_MDEFORMVERT | CD_MASK_PAINT_MASK | CD_MASK_MVERT_SKIN | CD_MASK_SHAPEKEY |
@@ -1701,7 +1704,7 @@ const CustomData_MeshMasks CD_MASK_EDITMESH = {
     .fmask = 0,
     .lmask = (CD_MASK_MDISPS | CD_MASK_MLOOPUV | CD_MASK_MLOOPCOL | CD_MASK_CUSTOMLOOPNORMAL |
               CD_MASK_GRID_PAINT_MASK | CD_MASK_GENERIC_DATA),
-    .pmask = (CD_MASK_RECAST | CD_MASK_FACEMAP | CD_MASK_GENERIC_DATA),
+    .pmask = (CD_MASK_RECAST | CD_MASK_FACEMAP | CD_MASK_GENERIC_DATA | CD_MASK_SCULPT_FACE_SETS),
 };
 const CustomData_MeshMasks CD_MASK_DERIVEDMESH = {
     .vmask = (CD_MASK_ORIGINDEX | CD_MASK_MDEFORMVERT | CD_MASK_SHAPEKEY | CD_MASK_MVERT_SKIN |
@@ -1712,7 +1715,7 @@ const CustomData_MeshMasks CD_MASK_DERIVEDMESH = {
               CD_MASK_PREVIEW_MLOOPCOL | CD_MASK_ORIGSPACE_MLOOP |
               CD_MASK_GENERIC_DATA), /* XXX MISSING CD_MASK_MLOOPTANGENT ? */
     .pmask = (CD_MASK_ORIGINDEX | CD_MASK_RECAST | CD_MASK_FREESTYLE_FACE | CD_MASK_FACEMAP |
-              CD_MASK_GENERIC_DATA),
+              CD_MASK_GENERIC_DATA | CD_MASK_SCULPT_FACE_SETS),
 };
 const CustomData_MeshMasks CD_MASK_BMESH = {
     .vmask = (CD_MASK_MDEFORMVERT | CD_MASK_BWEIGHT | CD_MASK_MVERT_SKIN | CD_MASK_SHAPEKEY |
@@ -1721,7 +1724,8 @@ const CustomData_MeshMasks CD_MASK_BMESH = {
     .fmask = 0,
     .lmask = (CD_MASK_MDISPS | CD_MASK_MLOOPUV | CD_MASK_MLOOPCOL | CD_MASK_CUSTOMLOOPNORMAL |
               CD_MASK_GRID_PAINT_MASK | CD_MASK_GENERIC_DATA),
-    .pmask = (CD_MASK_RECAST | CD_MASK_FREESTYLE_FACE | CD_MASK_FACEMAP | CD_MASK_GENERIC_DATA),
+    .pmask = (CD_MASK_RECAST | CD_MASK_FREESTYLE_FACE | CD_MASK_FACEMAP | CD_MASK_GENERIC_DATA |
+              CD_MASK_SCULPT_FACE_SETS),
 };
 /**
  * cover values copied by #BKE_mesh_loops_to_tessdata
@@ -1750,7 +1754,8 @@ const CustomData_MeshMasks CD_MASK_EVERYTHING = {
               CD_MASK_MLOOPTANGENT | CD_MASK_PREVIEW_MLOOPCOL | CD_MASK_ORIGSPACE_MLOOP |
               CD_MASK_GRID_PAINT_MASK | CD_MASK_GENERIC_DATA),
     .pmask = (CD_MASK_MPOLY | CD_MASK_BM_ELEM_PYPTR | CD_MASK_ORIGINDEX | CD_MASK_NORMAL |
-              CD_MASK_RECAST | CD_MASK_FACEMAP | CD_MASK_FREESTYLE_FACE | CD_MASK_GENERIC_DATA),
+              CD_MASK_RECAST | CD_MASK_FACEMAP | CD_MASK_FREESTYLE_FACE | CD_MASK_GENERIC_DATA |
+              CD_MASK_SCULPT_FACE_SETS),
 };
 
 static const LayerTypeInfo *layerType_getInfo(int type)
@@ -4221,7 +4226,7 @@ bool CustomData_verify_versions(struct CustomData *data, int index)
     /* 0 structnum is used in writing code to tag layer types that should not be written. */
     else if (typeInfo->structnum == 0 &&
              /* XXX Not sure why those three are exception, maybe that should be fixed? */
-             !ELEM(layer->type, CD_PAINT_MASK, CD_FACEMAP, CD_MTEXPOLY)) {
+             !ELEM(layer->type, CD_PAINT_MASK, CD_FACEMAP, CD_MTEXPOLY, CD_SCULPT_FACE_SETS)) {
       keeplayer = false;
       CLOG_WARN(&LOG, ".blend file read: removing a data layer that should not have been written");
     }