Sculpt: Mask Init operator

This operator initializes mask values for the entire mesh. It supports
different modes for initializing those values, and more will be added in
the future.

The initial version supports generating a random mask per vertex, Face
Sets or loose parts. These masks are useful for introducing variations
in the model using the filters (both shapes and colors).

Reviewed By: JacquesLucke

Differential Revision: https://developer.blender.org/D10679

4 files changed, 204 insertions, 0 deletions

diff --git a/source/blender/editors/sculpt_paint/CMakeLists.txt b/source/blender/editors/sculpt_paint/CMakeLists.txt
index fff172c0707..3b668a1bd4c 100644
--- a/source/blender/editors/sculpt_paint/CMakeLists.txt
+++ b/source/blender/editors/sculpt_paint/CMakeLists.txt
@@ -68,6 +68,7 @@ set(SRC
   sculpt_filter_mesh.c
   sculpt_geodesic.c
   sculpt_mask_expand.c
+  sculpt_mask_init.c
   sculpt_multiplane_scrape.c
   sculpt_paint_color.c
   sculpt_pose.c
diff --git a/source/blender/editors/sculpt_paint/sculpt.c b/source/blender/editors/sculpt_paint/sculpt.c
index 0b30303de91..d32391bfb67 100644
--- a/source/blender/editors/sculpt_paint/sculpt.c
+++ b/source/blender/editors/sculpt_paint/sculpt.c
@@ -9461,6 +9461,7 @@ void ED_operatortypes_sculpt(void)
   WM_operatortype_append(SCULPT_OT_color_filter);
   WM_operatortype_append(SCULPT_OT_mask_by_color);
   WM_operatortype_append(SCULPT_OT_dyntopo_detail_size_edit);
+  WM_operatortype_append(SCULPT_OT_mask_init);
 
   WM_operatortype_append(SCULPT_OT_expand);
 }
diff --git a/source/blender/editors/sculpt_paint/sculpt_intern.h b/source/blender/editors/sculpt_paint/sculpt_intern.h
index c323a4d744a..087cb6dd94a 100644
--- a/source/blender/editors/sculpt_paint/sculpt_intern.h
+++ b/source/blender/editors/sculpt_paint/sculpt_intern.h
@@ -792,6 +792,9 @@ typedef struct SculptThreadedTaskData {
   int face_set;
   int filter_undo_type;
 
+  int mask_init_mode;
+  int mask_init_seed;
+
   ThreadMutex mutex;
 
 } SculptThreadedTaskData;
@@ -1356,6 +1359,9 @@ void SCULPT_OT_dirty_mask(struct wmOperatorType *ot);
 /* Mask and Face Sets Expand. */
 void SCULPT_OT_mask_expand(struct wmOperatorType *ot);
 
+/* Mask Init. */
+void SCULPT_OT_mask_init(struct wmOperatorType *ot);
+
 /* Detail size. */
 void SCULPT_OT_detail_flood_fill(struct wmOperatorType *ot);
 void SCULPT_OT_sample_detail_size(struct wmOperatorType *ot);
diff --git a/source/blender/editors/sculpt_paint/sculpt_mask_init.c b/source/blender/editors/sculpt_paint/sculpt_mask_init.c
new file mode 100644
index 00000000000..b2fae9198fd
--- /dev/null
+++ b/source/blender/editors/sculpt_paint/sculpt_mask_init.c
@@ -0,0 +1,196 @@
+/*
+ * This program is free software; you can redistribute it and/or
+ * modify it under the terms of the GNU General Public License
+ * as published by the Free Software Foundation; either version 2
+ * of the License, or (at your option) any later version.
+ *
+ * This program is distributed in the hope that it will be useful,
+ * but WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+ * GNU General Public License for more details.
+ *
+ * You should have received a copy of the GNU General Public License
+ * along with this program; if not, write to the Free Software Foundation,
+ * Inc., 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301, USA.
+ *
+ * The Original Code is Copyright (C) 2021 Blender Foundation.
+ * All rights reserved.
+ */
+
+/** \file
+ * \ingroup edsculpt
+ */
+
+#include "MEM_guardedalloc.h"
+
+#include "BLI_blenlib.h"
+#include "BLI_math.h"
+#include "BLI_hash.h"
+#include "BLI_task.h"
+
+#include "BLT_translation.h"
+
+#include "PIL_time.h"
+
+#include "DNA_brush_types.h"
+#include "DNA_mesh_types.h"
+#include "DNA_meshdata_types.h"
+#include "DNA_object_types.h"
+
+#include "BKE_brush.h"
+#include "BKE_ccg.h"
+#include "BKE_context.h"
+#include "BKE_mesh.h"
+#include "BKE_multires.h"
+#include "BKE_node.h"
+#include "BKE_object.h"
+#include "BKE_paint.h"
+#include "BKE_pbvh.h"
+
+#include "DEG_depsgraph.h"
+
+#include "WM_api.h"
+#include "WM_types.h"
+
+#include "RNA_access.h"
+#include "RNA_define.h"
+
+#include "ED_sculpt.h"
+#include "paint_intern.h"
+#include "sculpt_intern.h"
+
+#include "bmesh.h"
+
+#include <math.h>
+#include <stdlib.h>
+
+/* Mask Init operator. */
+/* Initializes mask values for the entire mesh depending on the mode. */
+
+typedef enum eSculptMaskInitMode {
+  SCULPT_MASK_INIT_RANDOM_PER_VERTEX,
+  SCULPT_MASK_INIT_RANDOM_PER_FACE_SET,
+  SCULPT_MASK_INIT_RANDOM_PER_LOOSE_PART,
+} eSculptMaskInitMode;
+
+static EnumPropertyItem prop_sculpt_mask_init_mode_types[] = {
+    {
+        SCULPT_MASK_INIT_RANDOM_PER_VERTEX,
+        "RANDOM_PER_VERTEX",
+        0,
+        "Random per Vertex",
+        "",
+    },
+    {
+        SCULPT_MASK_INIT_RANDOM_PER_FACE_SET,
+        "RANDOM_PER_FACE_SET",
+        0,
+        "Random per Face Set",
+        "",
+    },
+    {
+        SCULPT_MASK_INIT_RANDOM_PER_LOOSE_PART,
+        "RANDOM_PER_LOOSE_PART",
+        0,
+        "Random per Loose Part",
+        "",
+    },
+    {0, NULL, 0, NULL, NULL},
+};
+
+static void mask_init_task_cb(void *__restrict userdata,
+                              const int i,
+                              const TaskParallelTLS *__restrict UNUSED(tls))
+{
+  SculptThreadedTaskData *data = userdata;
+  SculptSession *ss = data->ob->sculpt;
+  PBVHNode *node = data->nodes[i];
+  PBVHVertexIter vd;
+  const int mode = data->mask_init_mode;
+  const int seed = data->mask_init_seed;
+  SCULPT_undo_push_node(data->ob, node, SCULPT_UNDO_MASK);
+  BKE_pbvh_vertex_iter_begin(ss->pbvh, node, vd, PBVH_ITER_UNIQUE)
+  {
+    switch (mode) {
+      case SCULPT_MASK_INIT_RANDOM_PER_VERTEX:
+        *vd.mask = BLI_hash_int_01(vd.index + seed);
+        break;
+      case SCULPT_MASK_INIT_RANDOM_PER_FACE_SET: {
+        const int face_set = SCULPT_vertex_face_set_get(ss, vd.index);
+        *vd.mask = BLI_hash_int_01(face_set + seed);
+        break;
+      }
+      case SCULPT_MASK_INIT_RANDOM_PER_LOOSE_PART:
+        *vd.mask = BLI_hash_int_01(ss->vertex_info.connected_component[vd.index] + seed);
+        break;
+    }
+  }
+  BKE_pbvh_vertex_iter_end;
+  BKE_pbvh_node_mark_update_mask(data->nodes[i]);
+}
+
+static int sculpt_mask_init_exec(bContext *C, wmOperator *op)
+{
+  Object *ob = CTX_data_active_object(C);
+  SculptSession *ss = ob->sculpt;
+  Depsgraph *depsgraph = CTX_data_ensure_evaluated_depsgraph(C);
+
+  const int mode = RNA_enum_get(op->ptr, "mode");
+
+  BKE_sculpt_update_object_for_edit(depsgraph, ob, true, true, false);
+
+  PBVH *pbvh = ob->sculpt->pbvh;
+  PBVHNode **nodes;
+  int totnode;
+  BKE_pbvh_search_gather(pbvh, NULL, NULL, &nodes, &totnode);
+
+  if (totnode == 0) {
+    return OPERATOR_CANCELLED;
+  }
+
+  SCULPT_undo_push_begin(ob, "init mask");
+
+  if (mode == SCULPT_MASK_INIT_RANDOM_PER_LOOSE_PART) {
+    SCULPT_connected_components_ensure(ob);
+  }
+
+  SculptThreadedTaskData data = {
+      .ob = ob,
+      .nodes = nodes,
+      .mask_init_mode = mode,
+      .mask_init_seed = PIL_check_seconds_timer(),
+  };
+
+  TaskParallelSettings settings;
+  BKE_pbvh_parallel_range_settings(&settings, true, totnode);
+  BLI_task_parallel_range(0, totnode, &data, mask_init_task_cb, &settings);
+
+  multires_stitch_grids(ob);
+
+  SCULPT_undo_push_end();
+
+  BKE_pbvh_update_vertex_data(ss->pbvh, PBVH_UpdateMask);
+  MEM_SAFE_FREE(nodes);
+  SCULPT_tag_update_overlays(C);
+  return OPERATOR_FINISHED;
+}
+
+void SCULPT_OT_mask_init(wmOperatorType *ot)
+{
+  /* identifiers */
+  ot->name = "Init Mask";
+  ot->description = "Creates a new mask for the entire mesh";
+  ot->idname = "SCULPT_OT_mask_init";
+
+  /* api callbacks */
+  ot->exec = sculpt_mask_init_exec;
+  ot->poll = SCULPT_mode_poll;
+
+  ot->flag = OPTYPE_REGISTER | OPTYPE_UNDO;
+  RNA_def_enum(ot->srna,
+               "mode",
+               prop_sculpt_mask_init_mode_types,
+               SCULPT_MASK_INIT_RANDOM_PER_VERTEX,
+               "Mode",
+               "");
+}