Cleanup: Move Mask Filter and Mask Expand to their own files

8 files changed, 1071 insertions, 924 deletions

diff --git a/source/blender/editors/sculpt_paint/CMakeLists.txt b/source/blender/editors/sculpt_paint/CMakeLists.txt
index 81dafd5ded4..f9858804394 100644
--- a/source/blender/editors/sculpt_paint/CMakeLists.txt
+++ b/source/blender/editors/sculpt_paint/CMakeLists.txt
@@ -62,7 +62,9 @@ set(SRC
   sculpt_automasking.c
   sculpt_cloth.c
   sculpt_face_set.c
+  sculpt_filter_mask.c
   sculpt_filter_mesh.c
+  sculpt_mask_expand.c
   sculpt_multiplane_scrape.c
   sculpt_pose.c
   sculpt_smooth.c
diff --git a/source/blender/editors/sculpt_paint/sculpt.c b/source/blender/editors/sculpt_paint/sculpt.c
index a53c9aed36d..5bd0f3f2f48 100644
--- a/source/blender/editors/sculpt_paint/sculpt.c
+++ b/source/blender/editors/sculpt_paint/sculpt.c
@@ -153,7 +153,7 @@ const float *SCULPT_vertex_co_get(SculptSession *ss, int index)
   return NULL;
 }
 
-static void SCULPT_vertex_normal_get(SculptSession *ss, int index, float no[3])
+void SCULPT_vertex_normal_get(SculptSession *ss, int index, float no[3])
 {
   switch (BKE_pbvh_type(ss->pbvh)) {
     case PBVH_FACES:
@@ -209,7 +209,7 @@ const float *SCULPT_active_vertex_co_get(SculptSession *ss)
   return SCULPT_vertex_co_get(ss, SCULPT_active_vertex_get(ss));
 }
 
-static void SCULPT_active_vertex_normal_get(SculptSession *ss, float normal[3])
+void SCULPT_active_vertex_normal_get(SculptSession *ss, float normal[3])
 {
   SCULPT_vertex_normal_get(ss, SCULPT_active_vertex_get(ss), normal);
 }
@@ -8463,895 +8463,6 @@ static void SCULPT_OT_set_detail_size(wmOperatorType *ot)
   ot->flag = OPTYPE_REGISTER | OPTYPE_UNDO;
 }
 
-typedef enum eSculptMaskFilterTypes {
-  MASK_FILTER_SMOOTH = 0,
-  MASK_FILTER_SHARPEN = 1,
-  MASK_FILTER_GROW = 2,
-  MASK_FILTER_SHRINK = 3,
-  MASK_FILTER_CONTRAST_INCREASE = 5,
-  MASK_FILTER_CONTRAST_DECREASE = 6,
-} eSculptMaskFilterTypes;
-
-static EnumPropertyItem prop_mask_filter_types[] = {
-    {MASK_FILTER_SMOOTH, "SMOOTH", 0, "Smooth Mask", "Smooth mask"},
-    {MASK_FILTER_SHARPEN, "SHARPEN", 0, "Sharpen Mask", "Sharpen mask"},
-    {MASK_FILTER_GROW, "GROW", 0, "Grow Mask", "Grow mask"},
-    {MASK_FILTER_SHRINK, "SHRINK", 0, "Shrink Mask", "Shrink mask"},
-    {MASK_FILTER_CONTRAST_INCREASE,
-     "CONTRAST_INCREASE",
-     0,
-     "Increase contrast",
-     "Increase the contrast of the paint mask"},
-    {MASK_FILTER_CONTRAST_DECREASE,
-     "CONTRAST_DECREASE",
-     0,
-     "Decrease contrast",
-     "Decrease the contrast of the paint mask"},
-    {0, NULL, 0, NULL, NULL},
-};
-
-static void mask_filter_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];
-  bool update = false;
-
-  const int mode = data->filter_type;
-  float contrast = 0.0f;
-
-  PBVHVertexIter vd;
-
-  if (mode == MASK_FILTER_CONTRAST_INCREASE) {
-    contrast = 0.1f;
-  }
-
-  if (mode == MASK_FILTER_CONTRAST_DECREASE) {
-    contrast = -0.1f;
-  }
-
-  BKE_pbvh_vertex_iter_begin(ss->pbvh, node, vd, PBVH_ITER_UNIQUE)
-  {
-    float delta, gain, offset, max, min;
-    float prev_val = *vd.mask;
-    SculptVertexNeighborIter ni;
-    switch (mode) {
-      case MASK_FILTER_SMOOTH:
-      case MASK_FILTER_SHARPEN: {
-        float val = SCULPT_neighbor_mask_average(ss, vd.index);
-
-        val -= *vd.mask;
-
-        if (mode == MASK_FILTER_SMOOTH) {
-          *vd.mask += val;
-        }
-        else if (mode == MASK_FILTER_SHARPEN) {
-          if (*vd.mask > 0.5f) {
-            *vd.mask += 0.05f;
-          }
-          else {
-            *vd.mask -= 0.05f;
-          }
-          *vd.mask += val / 2.0f;
-        }
-        break;
-      }
-      case MASK_FILTER_GROW:
-        max = 0.0f;
-        SCULPT_VERTEX_NEIGHBORS_ITER_BEGIN (ss, vd.index, ni) {
-          float vmask_f = data->prev_mask[ni.index];
-          if (vmask_f > max) {
-            max = vmask_f;
-          }
-        }
-        SCULPT_VERTEX_NEIGHBORS_ITER_END(ni);
-        *vd.mask = max;
-        break;
-      case MASK_FILTER_SHRINK:
-        min = 1.0f;
-        SCULPT_VERTEX_NEIGHBORS_ITER_BEGIN (ss, vd.index, ni) {
-          float vmask_f = data->prev_mask[ni.index];
-          if (vmask_f < min) {
-            min = vmask_f;
-          }
-        }
-        SCULPT_VERTEX_NEIGHBORS_ITER_END(ni);
-        *vd.mask = min;
-        break;
-      case MASK_FILTER_CONTRAST_INCREASE:
-      case MASK_FILTER_CONTRAST_DECREASE:
-        delta = contrast / 2.0f;
-        gain = 1.0f - delta * 2.0f;
-        if (contrast > 0) {
-          gain = 1.0f / ((gain != 0.0f) ? gain : FLT_EPSILON);
-          offset = gain * (-delta);
-        }
-        else {
-          delta *= -1.0f;
-          offset = gain * (delta);
-        }
-        *vd.mask = gain * (*vd.mask) + offset;
-        break;
-    }
-    CLAMP(*vd.mask, 0.0f, 1.0f);
-    if (*vd.mask != prev_val) {
-      update = true;
-    }
-    if (vd.mvert) {
-      vd.mvert->flag |= ME_VERT_PBVH_UPDATE;
-    }
-  }
-  BKE_pbvh_vertex_iter_end;
-
-  if (update) {
-    BKE_pbvh_node_mark_update_mask(node);
-  }
-}
-
-static int sculpt_mask_filter_exec(bContext *C, wmOperator *op)
-{
-  ARegion *region = CTX_wm_region(C);
-  Object *ob = CTX_data_active_object(C);
-  SculptSession *ss = ob->sculpt;
-  Depsgraph *depsgraph = CTX_data_depsgraph_pointer(C);
-  PBVH *pbvh = ob->sculpt->pbvh;
-  PBVHNode **nodes;
-  Sculpt *sd = CTX_data_tool_settings(C)->sculpt;
-  int totnode;
-  int filter_type = RNA_enum_get(op->ptr, "filter_type");
-
-  BKE_sculpt_update_object_for_edit(depsgraph, ob, true, true);
-
-  SCULPT_vertex_random_access_init(ss);
-
-  if (!ob->sculpt->pmap) {
-    return OPERATOR_CANCELLED;
-  }
-
-  int num_verts = SCULPT_vertex_count_get(ss);
-
-  BKE_pbvh_search_gather(pbvh, NULL, NULL, &nodes, &totnode);
-  SCULPT_undo_push_begin("Mask filter");
-
-  for (int i = 0; i < totnode; i++) {
-    SCULPT_undo_push_node(ob, nodes[i], SCULPT_UNDO_MASK);
-  }
-
-  float *prev_mask = NULL;
-  int iterations = RNA_int_get(op->ptr, "iterations");
-
-  /* Auto iteration count calculates the number of iteration based on the vertices of the mesh to
-   * avoid adding an unnecessary amount of undo steps when using the operator from a shortcut.
-   * One iteration per 50000 vertices in the mesh should be fine in most cases.
-   * Maybe we want this to be configurable. */
-  if (RNA_boolean_get(op->ptr, "auto_iteration_count")) {
-    iterations = (int)(num_verts / 50000.0f) + 1;
-  }
-
-  for (int i = 0; i < iterations; i++) {
-    if (ELEM(filter_type, MASK_FILTER_GROW, MASK_FILTER_SHRINK)) {
-      prev_mask = MEM_mallocN(num_verts * sizeof(float), "prevmask");
-      for (int j = 0; j < num_verts; j++) {
-        prev_mask[j] = SCULPT_vertex_mask_get(ss, j);
-      }
-    }
-
-    SculptThreadedTaskData data = {
-        .sd = sd,
-        .ob = ob,
-        .nodes = nodes,
-        .filter_type = filter_type,
-        .prev_mask = prev_mask,
-    };
-
-    PBVHParallelSettings settings;
-    BKE_pbvh_parallel_range_settings(&settings, (sd->flags & SCULPT_USE_OPENMP), totnode);
-    BKE_pbvh_parallel_range(0, totnode, &data, mask_filter_task_cb, &settings);
-
-    if (ELEM(filter_type, MASK_FILTER_GROW, MASK_FILTER_SHRINK)) {
-      MEM_freeN(prev_mask);
-    }
-  }
-
-  MEM_SAFE_FREE(nodes);
-
-  SCULPT_undo_push_end();
-
-  ED_region_tag_redraw(region);
-  WM_event_add_notifier(C, NC_OBJECT | ND_DRAW, ob);
-  return OPERATOR_FINISHED;
-}
-
-static void SCULPT_OT_mask_filter(struct wmOperatorType *ot)
-{
-  /* Identifiers. */
-  ot->name = "Mask Filter";
-  ot->idname = "SCULPT_OT_mask_filter";
-  ot->description = "Applies a filter to modify the current mask";
-
-  /* API callbacks. */
-  ot->exec = sculpt_mask_filter_exec;
-  ot->poll = SCULPT_mode_poll;
-
-  ot->flag = OPTYPE_REGISTER;
-
-  /* RNA. */
-  RNA_def_enum(ot->srna,
-               "filter_type",
-               prop_mask_filter_types,
-               MASK_FILTER_SMOOTH,
-               "Type",
-               "Filter that is going to be applied to the mask");
-  RNA_def_int(ot->srna,
-              "iterations",
-              1,
-              1,
-              100,
-              "Iterations",
-              "Number of times that the filter is going to be applied",
-              1,
-              100);
-  RNA_def_boolean(
-      ot->srna,
-      "auto_iteration_count",
-      false,
-      "Auto Iteration Count",
-      "Use a automatic number of iterations based on the number of vertices of the sculpt");
-}
-
-static float neighbor_dirty_mask(SculptSession *ss, PBVHVertexIter *vd)
-{
-  int total = 0;
-  float avg[3];
-  zero_v3(avg);
-
-  SculptVertexNeighborIter ni;
-  SCULPT_VERTEX_NEIGHBORS_ITER_BEGIN (ss, vd->index, ni) {
-    float normalized[3];
-    sub_v3_v3v3(normalized, SCULPT_vertex_co_get(ss, ni.index), vd->co);
-    normalize_v3(normalized);
-    add_v3_v3(avg, normalized);
-    total++;
-  }
-  SCULPT_VERTEX_NEIGHBORS_ITER_END(ni);
-
-  if (total > 0) {
-    mul_v3_fl(avg, 1.0f / total);
-    float normal[3];
-    if (vd->no) {
-      normal_short_to_float_v3(normal, vd->no);
-    }
-    else {
-      copy_v3_v3(normal, vd->fno);
-    }
-    float dot = dot_v3v3(avg, normal);
-    float angle = max_ff(saacosf(dot), 0.0f);
-    return angle;
-  }
-  return 0.0f;
-}
-
-typedef struct DirtyMaskRangeData {
-  float min, max;
-} DirtyMaskRangeData;
-
-static void dirty_mask_compute_range_task_cb(void *__restrict userdata,
-                                             const int i,
-                                             const TaskParallelTLS *__restrict tls)
-{
-  SculptThreadedTaskData *data = userdata;
-  SculptSession *ss = data->ob->sculpt;
-  PBVHNode *node = data->nodes[i];
-  DirtyMaskRangeData *range = tls->userdata_chunk;
-  PBVHVertexIter vd;
-
-  BKE_pbvh_vertex_iter_begin(ss->pbvh, node, vd, PBVH_ITER_UNIQUE)
-  {
-    float dirty_mask = neighbor_dirty_mask(ss, &vd);
-    range->min = min_ff(dirty_mask, range->min);
-    range->max = max_ff(dirty_mask, range->max);
-  }
-  BKE_pbvh_vertex_iter_end;
-}
-
-static void dirty_mask_compute_range_reduce(const void *__restrict UNUSED(userdata),
-                                            void *__restrict chunk_join,
-                                            void *__restrict chunk)
-{
-  DirtyMaskRangeData *join = chunk_join;
-  DirtyMaskRangeData *range = chunk;
-  join->min = min_ff(range->min, join->min);
-  join->max = max_ff(range->max, join->max);
-}
-
-static void dirty_mask_apply_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 bool dirty_only = data->dirty_mask_dirty_only;
-  const float min = data->dirty_mask_min;
-  const float max = data->dirty_mask_max;
-
-  float range = max - min;
-  if (range < 0.0001f) {
-    range = 0.0f;
-  }
-  else {
-    range = 1.0f / range;
-  }
-
-  BKE_pbvh_vertex_iter_begin(ss->pbvh, node, vd, PBVH_ITER_UNIQUE)
-  {
-    float dirty_mask = neighbor_dirty_mask(ss, &vd);
-    float mask = *vd.mask + (1.0f - ((dirty_mask - min) * range));
-    if (dirty_only) {
-      mask = fminf(mask, 0.5f) * 2.0f;
-    }
-    *vd.mask = CLAMPIS(mask, 0.0f, 1.0f);
-
-    if (vd.mvert) {
-      vd.mvert->flag |= ME_VERT_PBVH_UPDATE;
-    }
-  }
-  BKE_pbvh_vertex_iter_end;
-  BKE_pbvh_node_mark_update_mask(node);
-}
-
-static int sculpt_dirty_mask_exec(bContext *C, wmOperator *op)
-{
-  ARegion *region = CTX_wm_region(C);
-  Object *ob = CTX_data_active_object(C);
-  SculptSession *ss = ob->sculpt;
-  Depsgraph *depsgraph = CTX_data_depsgraph_pointer(C);
-  PBVH *pbvh = ob->sculpt->pbvh;
-  PBVHNode **nodes;
-  Sculpt *sd = CTX_data_tool_settings(C)->sculpt;
-  int totnode;
-
-  BKE_sculpt_update_object_for_edit(depsgraph, ob, true, true);
-
-  SCULPT_vertex_random_access_init(ss);
-
-  if (!ob->sculpt->pmap) {
-    return OPERATOR_CANCELLED;
-  }
-
-  BKE_pbvh_search_gather(pbvh, NULL, NULL, &nodes, &totnode);
-  SCULPT_undo_push_begin("Dirty Mask");
-
-  for (int i = 0; i < totnode; i++) {
-    SCULPT_undo_push_node(ob, nodes[i], SCULPT_UNDO_MASK);
-  }
-
-  SculptThreadedTaskData data = {
-      .sd = sd,
-      .ob = ob,
-      .nodes = nodes,
-      .dirty_mask_dirty_only = RNA_boolean_get(op->ptr, "dirty_only"),
-  };
-  DirtyMaskRangeData range = {
-      .min = FLT_MAX,
-      .max = -FLT_MAX,
-  };
-
-  PBVHParallelSettings settings;
-  BKE_pbvh_parallel_range_settings(&settings, (sd->flags & SCULPT_USE_OPENMP), totnode);
-
-  settings.func_reduce = dirty_mask_compute_range_reduce;
-  settings.userdata_chunk = &range;
-  settings.userdata_chunk_size = sizeof(DirtyMaskRangeData);
-
-  BKE_pbvh_parallel_range(0, totnode, &data, dirty_mask_compute_range_task_cb, &settings);
-  data.dirty_mask_min = range.min;
-  data.dirty_mask_max = range.max;
-  BKE_pbvh_parallel_range(0, totnode, &data, dirty_mask_apply_task_cb, &settings);
-
-  MEM_SAFE_FREE(nodes);
-
-  BKE_pbvh_update_vertex_data(pbvh, PBVH_UpdateMask);
-
-  SCULPT_undo_push_end();
-
-  ED_region_tag_redraw(region);
-
-  WM_event_add_notifier(C, NC_OBJECT | ND_DRAW, ob);
-
-  return OPERATOR_FINISHED;
-}
-
-static void SCULPT_OT_dirty_mask(struct wmOperatorType *ot)
-{
-  /* Identifiers. */
-  ot->name = "Dirty Mask";
-  ot->idname = "SCULPT_OT_dirty_mask";
-  ot->description = "Generates a mask based on the geometry cavity and pointiness";
-
-  /* API callbacks. */
-  ot->exec = sculpt_dirty_mask_exec;
-  ot->poll = SCULPT_mode_poll;
-
-  ot->flag = OPTYPE_REGISTER;
-
-  /* RNA. */
-  RNA_def_boolean(
-      ot->srna, "dirty_only", false, "Dirty Only", "Don't calculate cleans for convex areas");
-}
-
-static void sculpt_mask_expand_cancel(bContext *C, wmOperator *op)
-{
-  Object *ob = CTX_data_active_object(C);
-  SculptSession *ss = ob->sculpt;
-  const bool create_face_set = RNA_boolean_get(op->ptr, "create_face_set");
-
-  MEM_freeN(op->customdata);
-
-  for (int n = 0; n < ss->filter_cache->totnode; n++) {
-    PBVHNode *node = ss->filter_cache->nodes[n];
-    if (create_face_set) {
-      for (int i = 0; i < ss->totfaces; i++) {
-        ss->face_sets[i] = ss->filter_cache->prev_face_set[i];
-      }
-    }
-    else {
-      PBVHVertexIter vd;
-      BKE_pbvh_vertex_iter_begin(ss->pbvh, node, vd, PBVH_ITER_UNIQUE)
-      {
-        *vd.mask = ss->filter_cache->prev_mask[vd.index];
-      }
-      BKE_pbvh_vertex_iter_end;
-    }
-
-    BKE_pbvh_node_mark_redraw(node);
-  }
-
-  if (!create_face_set) {
-    SCULPT_flush_update_step(C, SCULPT_UPDATE_MASK);
-  }
-  SCULPT_filter_cache_free(ss);
-  SCULPT_undo_push_end();
-  SCULPT_flush_update_done(C, ob, SCULPT_UPDATE_MASK);
-  ED_workspace_status_text(C, NULL);
-}
-
-static void sculpt_expand_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;
-  int update_it = data->mask_expand_update_it;
-
-  BKE_pbvh_vertex_iter_begin(ss->pbvh, node, vd, PBVH_ITER_ALL)
-  {
-    int vi = vd.index;
-    float final_mask = *vd.mask;
-    if (data->mask_expand_use_normals) {
-      if (ss->filter_cache->normal_factor[SCULPT_active_vertex_get(ss)] <
-          ss->filter_cache->normal_factor[vd.index]) {
-        final_mask = 1.0f;
-      }
-      else {
-        final_mask = 0.0f;
-      }
-    }
-    else {
-      if (ss->filter_cache->mask_update_it[vi] <= update_it &&
-          ss->filter_cache->mask_update_it[vi] != 0) {
-        final_mask = 1.0f;
-      }
-      else {
-        final_mask = 0.0f;
-      }
-    }
-
-    if (data->mask_expand_create_face_set) {
-      if (final_mask == 1.0f) {
-        SCULPT_vertex_face_set_set(ss, vd.index, ss->filter_cache->new_face_set);
-      }
-      BKE_pbvh_node_mark_redraw(node);
-    }
-    else {
-
-      if (data->mask_expand_keep_prev_mask) {
-        final_mask = MAX2(ss->filter_cache->prev_mask[vd.index], final_mask);
-      }
-
-      if (data->mask_expand_invert_mask) {
-        final_mask = 1.0f - final_mask;
-      }
-
-      if (*vd.mask != final_mask) {
-        if (vd.mvert) {
-          vd.mvert->flag |= ME_VERT_PBVH_UPDATE;
-        }
-        *vd.mask = final_mask;
-        BKE_pbvh_node_mark_update_mask(node);
-      }
-    }
-  }
-  BKE_pbvh_vertex_iter_end;
-}
-
-static int sculpt_mask_expand_modal(bContext *C, wmOperator *op, const wmEvent *event)
-{
-  Depsgraph *depsgraph = CTX_data_depsgraph_pointer(C);
-  Object *ob = CTX_data_active_object(C);
-  SculptSession *ss = ob->sculpt;
-  Sculpt *sd = CTX_data_tool_settings(C)->sculpt;
-  ARegion *region = CTX_wm_region(C);
-  float prevclick_f[2];
-  copy_v2_v2(prevclick_f, op->customdata);
-  int prevclick[2] = {(int)prevclick_f[0], (int)prevclick_f[1]};
-  int len = (int)len_v2v2_int(prevclick, event->mval);
-  len = abs(len);
-  int mask_speed = RNA_int_get(op->ptr, "mask_speed");
-  int mask_expand_update_it = len / mask_speed;
-  mask_expand_update_it = mask_expand_update_it + 1;
-
-  const bool create_face_set = RNA_boolean_get(op->ptr, "create_face_set");
-
-  if (RNA_boolean_get(op->ptr, "use_cursor")) {
-    SculptCursorGeometryInfo sgi;
-    float mouse[2];
-    mouse[0] = event->mval[0];
-    mouse[1] = event->mval[1];
-    SCULPT_cursor_geometry_info_update(C, &sgi, mouse, false);
-    mask_expand_update_it = ss->filter_cache->mask_update_it[(int)SCULPT_active_vertex_get(ss)];
-  }
-
-  if ((event->type == EVT_ESCKEY && event->val == KM_PRESS) ||
-      (event->type == RIGHTMOUSE && event->val == KM_PRESS)) {
-    /* Returning OPERATOR_CANCELLED will leak memory due to not finishing
-     * undo. Better solution could be to make paint_mesh_restore_co work
-     * for this case. */
-    sculpt_mask_expand_cancel(C, op);
-    return OPERATOR_FINISHED;
-  }
-
-  if ((event->type == LEFTMOUSE && event->val == KM_RELEASE) ||
-      (event->type == EVT_RETKEY && event->val == KM_PRESS) ||
-      (event->type == EVT_PADENTER && event->val == KM_PRESS)) {
-
-    /* Smooth iterations. */
-    SculptThreadedTaskData data = {
-        .sd = sd,
-        .ob = ob,
-        .nodes = ss->filter_cache->nodes,
-        .filter_type = MASK_FILTER_SMOOTH,
-    };
-
-    int smooth_iterations = RNA_int_get(op->ptr, "smooth_iterations");
-    BKE_sculpt_update_object_for_edit(depsgraph, ob, true, false);
-    for (int i = 0; i < smooth_iterations; i++) {
-      PBVHParallelSettings settings;
-      BKE_pbvh_parallel_range_settings(
-          &settings, (sd->flags & SCULPT_USE_OPENMP), ss->filter_cache->totnode);
-      BKE_pbvh_parallel_range(0, ss->filter_cache->totnode, &data, mask_filter_task_cb, &settings);
-    }
-
-    /* Pivot position. */
-    if (RNA_boolean_get(op->ptr, "update_pivot")) {
-      const char symm = sd->paint.symmetry_flags & PAINT_SYMM_AXIS_ALL;
-      const float threshold = 0.2f;
-      float avg[3];
-      int total = 0;
-      zero_v3(avg);
-
-      for (int n = 0; n < ss->filter_cache->totnode; n++) {
-        PBVHVertexIter vd;
-        BKE_pbvh_vertex_iter_begin(ss->pbvh, ss->filter_cache->nodes[n], vd, PBVH_ITER_UNIQUE)
-        {
-          const float mask = (vd.mask) ? *vd.mask : 0.0f;
-          if (mask < (0.5f + threshold) && mask > (0.5f - threshold)) {
-            if (SCULPT_check_vertex_pivot_symmetry(
-                    vd.co, ss->filter_cache->mask_expand_initial_co, symm)) {
-              add_v3_v3(avg, vd.co);
-              total++;
-            }
-          }
-        }
-        BKE_pbvh_vertex_iter_end;
-      }
-
-      if (total > 0) {
-        mul_v3_fl(avg, 1.0f / total);
-        copy_v3_v3(ss->pivot_pos, avg);
-      }
-      WM_event_add_notifier(C, NC_GEOM | ND_SELECT, ob->data);
-    }
-
-    MEM_freeN(op->customdata);
-
-    for (int i = 0; i < ss->filter_cache->totnode; i++) {
-      BKE_pbvh_node_mark_redraw(ss->filter_cache->nodes[i]);
-    }
-
-    SCULPT_filter_cache_free(ss);
-
-    SCULPT_undo_push_end();
-    SCULPT_flush_update_done(C, ob, SCULPT_UPDATE_MASK);
-    ED_workspace_status_text(C, NULL);
-    return OPERATOR_FINISHED;
-  }
-
-  /* When pressing Ctrl, expand directly to the max number of iterations. This allows to flood fill
-   * mask and face sets by connectivity directly. */
-  if (event->ctrl) {
-    mask_expand_update_it = ss->filter_cache->mask_update_last_it - 1;
-  }
-
-  if (!ELEM(event->type, MOUSEMOVE, EVT_LEFTCTRLKEY, EVT_RIGHTCTRLKEY)) {
-    return OPERATOR_RUNNING_MODAL;
-  }
-
-  if (mask_expand_update_it == ss->filter_cache->mask_update_current_it) {
-    ED_region_tag_redraw(region);
-    return OPERATOR_RUNNING_MODAL;
-  }
-
-  if (mask_expand_update_it < ss->filter_cache->mask_update_last_it) {
-
-    if (create_face_set) {
-      for (int i = 0; i < ss->totfaces; i++) {
-        ss->face_sets[i] = ss->filter_cache->prev_face_set[i];
-      }
-    }
-    SculptThreadedTaskData data = {
-        .sd = sd,
-        .ob = ob,
-        .nodes = ss->filter_cache->nodes,
-        .mask_expand_update_it = mask_expand_update_it,
-        .mask_expand_use_normals = RNA_boolean_get(op->ptr, "use_normals"),
-        .mask_expand_invert_mask = RNA_boolean_get(op->ptr, "invert"),
-        .mask_expand_keep_prev_mask = RNA_boolean_get(op->ptr, "keep_previous_mask"),
-        .mask_expand_create_face_set = RNA_boolean_get(op->ptr, "create_face_set"),
-    };
-    PBVHParallelSettings settings;
-    BKE_pbvh_parallel_range_settings(
-        &settings, (sd->flags & SCULPT_USE_OPENMP), ss->filter_cache->totnode);
-    BKE_pbvh_parallel_range(0, ss->filter_cache->totnode, &data, sculpt_expand_task_cb, &settings);
-    ss->filter_cache->mask_update_current_it = mask_expand_update_it;
-  }
-
-  SCULPT_flush_update_step(C, SCULPT_UPDATE_MASK);
-
-  return OPERATOR_RUNNING_MODAL;
-}
-
-typedef struct MaskExpandFloodFillData {
-  float original_normal[3];
-  float edge_sensitivity;
-  bool use_normals;
-} MaskExpandFloodFillData;
-
-static bool mask_expand_floodfill_cb(
-    SculptSession *ss, int from_v, int to_v, bool is_duplicate, void *userdata)
-{
-  MaskExpandFloodFillData *data = userdata;
-
-  if (!is_duplicate) {
-    int to_it = ss->filter_cache->mask_update_it[from_v] + 1;
-    ss->filter_cache->mask_update_it[to_v] = to_it;
-    if (to_it > ss->filter_cache->mask_update_last_it) {
-      ss->filter_cache->mask_update_last_it = to_it;
-    }
-
-    if (data->use_normals) {
-      float current_normal[3], prev_normal[3];
-      SCULPT_vertex_normal_get(ss, to_v, current_normal);
-      SCULPT_vertex_normal_get(ss, from_v, prev_normal);
-      const float from_edge_factor = ss->filter_cache->edge_factor[from_v];
-      ss->filter_cache->edge_factor[to_v] = dot_v3v3(current_normal, prev_normal) *
-                                            from_edge_factor;
-      ss->filter_cache->normal_factor[to_v] = dot_v3v3(data->original_normal, current_normal) *
-                                              powf(from_edge_factor, data->edge_sensitivity);
-      CLAMP(ss->filter_cache->normal_factor[to_v], 0.0f, 1.0f);
-    }
-  }
-  else {
-    /* PBVH_GRIDS duplicate handling. */
-    ss->filter_cache->mask_update_it[to_v] = ss->filter_cache->mask_update_it[from_v];
-    if (data->use_normals) {
-      ss->filter_cache->edge_factor[to_v] = ss->filter_cache->edge_factor[from_v];
-      ss->filter_cache->normal_factor[to_v] = ss->filter_cache->normal_factor[from_v];
-    }
-  }
-
-  return true;
-}
-
-static int sculpt_mask_expand_invoke(bContext *C, wmOperator *op, const wmEvent *event)
-{
-  Depsgraph *depsgraph = CTX_data_depsgraph_pointer(C);
-  Object *ob = CTX_data_active_object(C);
-  SculptSession *ss = ob->sculpt;
-  Sculpt *sd = CTX_data_tool_settings(C)->sculpt;
-  PBVH *pbvh = ob->sculpt->pbvh;
-
-  const bool use_normals = RNA_boolean_get(op->ptr, "use_normals");
-  const bool create_face_set = RNA_boolean_get(op->ptr, "create_face_set");
-
-  SculptCursorGeometryInfo sgi;
-  float mouse[2];
-  mouse[0] = event->mval[0];
-  mouse[1] = event->mval[1];
-
-  SCULPT_vertex_random_access_init(ss);
-
-  op->customdata = MEM_mallocN(2 * sizeof(float), "initial mouse position");
-  copy_v2_v2(op->customdata, mouse);
-
-  SCULPT_cursor_geometry_info_update(C, &sgi, mouse, false);
-
-  BKE_sculpt_update_object_for_edit(depsgraph, ob, true, true);
-
-  int vertex_count = SCULPT_vertex_count_get(ss);
-
-  ss->filter_cache = MEM_callocN(sizeof(FilterCache), "filter cache");
-
-  BKE_pbvh_search_gather(pbvh, NULL, NULL, &ss->filter_cache->nodes, &ss->filter_cache->totnode);
-
-  SCULPT_undo_push_begin("Mask Expand");
-
-  if (create_face_set) {
-    SCULPT_undo_push_node(ob, ss->filter_cache->nodes[0], SCULPT_UNDO_FACE_SETS);
-    for (int i = 0; i < ss->filter_cache->totnode; i++) {
-      BKE_pbvh_node_mark_redraw(ss->filter_cache->nodes[i]);
-    }
-  }
-  else {
-    for (int i = 0; i < ss->filter_cache->totnode; i++) {
-      SCULPT_undo_push_node(ob, ss->filter_cache->nodes[i], SCULPT_UNDO_MASK);
-      BKE_pbvh_node_mark_redraw(ss->filter_cache->nodes[i]);
-    }
-  }
-
-  ss->filter_cache->mask_update_it = MEM_callocN(sizeof(int) * vertex_count,
-                                                 "mask update iteration");
-  if (use_normals) {
-    ss->filter_cache->normal_factor = MEM_callocN(sizeof(float) * vertex_count,
-                                                  "mask update normal factor");
-    ss->filter_cache->edge_factor = MEM_callocN(sizeof(float) * vertex_count,
-                                                "mask update normal factor");
-    for (int i = 0; i < vertex_count; i++) {
-      ss->filter_cache->edge_factor[i] = 1.0f;
-    }
-  }
-
-  if (create_face_set) {
-    ss->filter_cache->prev_face_set = MEM_callocN(sizeof(float) * ss->totfaces, "prev face mask");
-    for (int i = 0; i < ss->totfaces; i++) {
-      ss->filter_cache->prev_face_set[i] = ss->face_sets[i];
-    }
-    ss->filter_cache->new_face_set = SCULPT_face_set_next_available_get(ss);
-  }
-  else {
-    ss->filter_cache->prev_mask = MEM_callocN(sizeof(float) * vertex_count, "prev mask");
-    for (int i = 0; i < vertex_count; i++) {
-      ss->filter_cache->prev_mask[i] = SCULPT_vertex_mask_get(ss, i);
-    }
-  }
-
-  ss->filter_cache->mask_update_last_it = 1;
-  ss->filter_cache->mask_update_current_it = 1;
-  ss->filter_cache->mask_update_it[SCULPT_active_vertex_get(ss)] = 0;
-
-  copy_v3_v3(ss->filter_cache->mask_expand_initial_co, SCULPT_active_vertex_co_get(ss));
-
-  SculptFloodFill flood;
-  SCULPT_floodfill_init(ss, &flood);
-  SCULPT_floodfill_add_active(sd, ob, ss, &flood, FLT_MAX);
-
-  MaskExpandFloodFillData fdata = {
-      .use_normals = use_normals,
-      .edge_sensitivity = RNA_int_get(op->ptr, "edge_sensitivity"),
-  };
-  SCULPT_active_vertex_normal_get(ss, fdata.original_normal);
-  SCULPT_floodfill_execute(ss, &flood, mask_expand_floodfill_cb, &fdata);
-  SCULPT_floodfill_free(&flood);
-
-  if (use_normals) {
-    for (int repeat = 0; repeat < 2; repeat++) {
-      for (int i = 0; i < vertex_count; i++) {
-        float avg = 0.0f;
-        SculptVertexNeighborIter ni;
-        SCULPT_VERTEX_NEIGHBORS_ITER_BEGIN (ss, i, ni) {
-          avg += ss->filter_cache->normal_factor[ni.index];
-        }
-        SCULPT_VERTEX_NEIGHBORS_ITER_END(ni);
-        ss->filter_cache->normal_factor[i] = avg / ni.size;
-      }
-    }
-
-    MEM_SAFE_FREE(ss->filter_cache->edge_factor);
-  }
-
-  SculptThreadedTaskData data = {
-      .sd = sd,
-      .ob = ob,
-      .nodes = ss->filter_cache->nodes,
-      .mask_expand_update_it = 0,
-      .mask_expand_use_normals = RNA_boolean_get(op->ptr, "use_normals"),
-      .mask_expand_invert_mask = RNA_boolean_get(op->ptr, "invert"),
-      .mask_expand_keep_prev_mask = RNA_boolean_get(op->ptr, "keep_previous_mask"),
-      .mask_expand_create_face_set = RNA_boolean_get(op->ptr, "create_face_set"),
-  };
-  PBVHParallelSettings settings;
-  BKE_pbvh_parallel_range_settings(
-      &settings, (sd->flags & SCULPT_USE_OPENMP), ss->filter_cache->totnode);
-  BKE_pbvh_parallel_range(0, ss->filter_cache->totnode, &data, sculpt_expand_task_cb, &settings);
-
-  const char *status_str = TIP_(
-      "Move the mouse to expand the mask from the active vertex. LMB: confirm mask, ESC/RMB: "
-      "cancel");
-  ED_workspace_status_text(C, status_str);
-
-  SCULPT_flush_update_step(C, SCULPT_UPDATE_MASK);
-  WM_event_add_modal_handler(C, op);
-  return OPERATOR_RUNNING_MODAL;
-}
-
-static void SCULPT_OT_mask_expand(wmOperatorType *ot)
-{
-  /* Identifiers. */
-  ot->name = "Mask Expand";
-  ot->idname = "SCULPT_OT_mask_expand";
-  ot->description = "Expands a mask from the initial active vertex under the cursor";
-
-  /* API callbacks. */
-  ot->invoke = sculpt_mask_expand_invoke;
-  ot->modal = sculpt_mask_expand_modal;
-  ot->cancel = sculpt_mask_expand_cancel;
-  ot->poll = SCULPT_mode_poll;
-
-  ot->flag = OPTYPE_REGISTER | OPTYPE_UNDO;
-  ot->prop = RNA_def_boolean(ot->srna, "invert", true, "Invert", "Invert the new mask");
-  ot->prop = RNA_def_boolean(
-      ot->srna, "use_cursor", true, "Use Cursor", "Expand the mask to the cursor position");
-  ot->prop = RNA_def_boolean(ot->srna,
-                             "update_pivot",
-                             true,
-                             "Update Pivot Position",
-                             "Set the pivot position to the mask border after creating the mask");
-  ot->prop = RNA_def_int(ot->srna, "smooth_iterations", 2, 0, 10, "Smooth iterations", "", 0, 10);
-  ot->prop = RNA_def_int(ot->srna, "mask_speed", 5, 1, 10, "Mask speed", "", 1, 10);
-
-  ot->prop = RNA_def_boolean(ot->srna,
-                             "use_normals",
-                             true,
-                             "Use Normals",
-                             "Generate the mask using the normals and curvature of the model");
-  ot->prop = RNA_def_boolean(ot->srna,
-                             "keep_previous_mask",
-                             false,
-                             "Keep Previous Mask",
-                             "Generate the new mask on top of the current one");
-  ot->prop = RNA_def_int(ot->srna,
-                         "edge_sensitivity",
-                         300,
-                         0,
-                         2000,
-                         "Edge Detection Sensitivity",
-                         "Sensitivity for expanding the mask across sculpted sharp edges when "
-                         "using normals to generate the mask",
-                         0,
-                         2000);
-  ot->prop = RNA_def_boolean(ot->srna,
-                             "create_face_set",
-                             false,
-                             "Expand Face Mask",
-                             "Expand a new Face Mask instead of the sculpt mask");
-}
-
 void SCULPT_geometry_preview_lines_update(bContext *C, SculptSession *ss, float radius)
 {
   Depsgraph *depsgraph = CTX_data_depsgraph_pointer(C);
diff --git a/source/blender/editors/sculpt_paint/sculpt_automasking.c b/source/blender/editors/sculpt_paint/sculpt_automasking.c
index 768b25a9a22..68fa7ac01ae 100644
--- a/source/blender/editors/sculpt_paint/sculpt_automasking.c
+++ b/source/blender/editors/sculpt_paint/sculpt_automasking.c
@@ -63,8 +63,8 @@
 #include <stdlib.h>
 
 bool SCULPT_is_automasking_mode_enabled(const Sculpt *sd,
-                                               const Brush *br,
-                                               const eAutomasking_flag mode)
+                                        const Brush *br,
+                                        const eAutomasking_flag mode)
 {
   return br->automasking_flags & mode || sd->automasking_flags & mode;
 }
@@ -205,9 +205,9 @@ static float *sculpt_face_sets_automasking_init(Sculpt *sd, Object *ob, float *a
 #define EDGE_DISTANCE_INF -1
 
 float *SCULPT_boundary_automasking_init(Object *ob,
-                                               eBoundaryAutomaskMode mode,
-                                               int propagation_steps,
-                                               float *automask_factor)
+                                        eBoundaryAutomaskMode mode,
+                                        int propagation_steps,
+                                        float *automask_factor)
 {
   SculptSession *ss = ob->sculpt;
 
diff --git a/source/blender/editors/sculpt_paint/sculpt_filter_mask.c b/source/blender/editors/sculpt_paint/sculpt_filter_mask.c
new file mode 100644
index 00000000000..d895ecc7119
--- /dev/null
+++ b/source/blender/editors/sculpt_paint/sculpt_filter_mask.c
@@ -0,0 +1,501 @@
+/*
+ * 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) 2020 Blender Foundation.
+ * All rights reserved.
+ */
+
+/** \file
+ * \ingroup edsculpt
+ */
+
+#include "MEM_guardedalloc.h"
+
+#include "BLI_blenlib.h"
+#include "BLI_hash.h"
+#include "BLI_math.h"
+#include "BLI_task.h"
+
+#include "DNA_mesh_types.h"
+#include "DNA_meshdata_types.h"
+
+#include "BKE_brush.h"
+#include "BKE_context.h"
+#include "BKE_mesh.h"
+#include "BKE_mesh_mapping.h"
+#include "BKE_object.h"
+#include "BKE_paint.h"
+#include "BKE_pbvh.h"
+#include "BKE_scene.h"
+
+#include "DEG_depsgraph.h"
+
+#include "WM_api.h"
+#include "WM_message.h"
+#include "WM_toolsystem.h"
+#include "WM_types.h"
+
+#include "ED_object.h"
+#include "ED_screen.h"
+#include "ED_sculpt.h"
+#include "paint_intern.h"
+#include "sculpt_intern.h"
+
+#include "RNA_access.h"
+#include "RNA_define.h"
+
+#include "UI_interface.h"
+
+#include "bmesh.h"
+
+#include <math.h>
+#include <stdlib.h>
+
+typedef enum eSculptMaskFilterTypes {
+  MASK_FILTER_SMOOTH = 0,
+  MASK_FILTER_SHARPEN = 1,
+  MASK_FILTER_GROW = 2,
+  MASK_FILTER_SHRINK = 3,
+  MASK_FILTER_CONTRAST_INCREASE = 5,
+  MASK_FILTER_CONTRAST_DECREASE = 6,
+} eSculptMaskFilterTypes;
+
+static EnumPropertyItem prop_mask_filter_types[] = {
+    {MASK_FILTER_SMOOTH, "SMOOTH", 0, "Smooth Mask", "Smooth mask"},
+    {MASK_FILTER_SHARPEN, "SHARPEN", 0, "Sharpen Mask", "Sharpen mask"},
+    {MASK_FILTER_GROW, "GROW", 0, "Grow Mask", "Grow mask"},
+    {MASK_FILTER_SHRINK, "SHRINK", 0, "Shrink Mask", "Shrink mask"},
+    {MASK_FILTER_CONTRAST_INCREASE,
+     "CONTRAST_INCREASE",
+     0,
+     "Increase contrast",
+     "Increase the contrast of the paint mask"},
+    {MASK_FILTER_CONTRAST_DECREASE,
+     "CONTRAST_DECREASE",
+     0,
+     "Decrease contrast",
+     "Decrease the contrast of the paint mask"},
+    {0, NULL, 0, NULL, NULL},
+};
+
+static void mask_filter_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];
+  bool update = false;
+
+  const int mode = data->filter_type;
+  float contrast = 0.0f;
+
+  PBVHVertexIter vd;
+
+  if (mode == MASK_FILTER_CONTRAST_INCREASE) {
+    contrast = 0.1f;
+  }
+
+  if (mode == MASK_FILTER_CONTRAST_DECREASE) {
+    contrast = -0.1f;
+  }
+
+  BKE_pbvh_vertex_iter_begin(ss->pbvh, node, vd, PBVH_ITER_UNIQUE)
+  {
+    float delta, gain, offset, max, min;
+    float prev_val = *vd.mask;
+    SculptVertexNeighborIter ni;
+    switch (mode) {
+      case MASK_FILTER_SMOOTH:
+      case MASK_FILTER_SHARPEN: {
+        float val = SCULPT_neighbor_mask_average(ss, vd.index);
+
+        val -= *vd.mask;
+
+        if (mode == MASK_FILTER_SMOOTH) {
+          *vd.mask += val;
+        }
+        else if (mode == MASK_FILTER_SHARPEN) {
+          if (*vd.mask > 0.5f) {
+            *vd.mask += 0.05f;
+          }
+          else {
+            *vd.mask -= 0.05f;
+          }
+          *vd.mask += val / 2.0f;
+        }
+        break;
+      }
+      case MASK_FILTER_GROW:
+        max = 0.0f;
+        SCULPT_VERTEX_NEIGHBORS_ITER_BEGIN (ss, vd.index, ni) {
+          float vmask_f = data->prev_mask[ni.index];
+          if (vmask_f > max) {
+            max = vmask_f;
+          }
+        }
+        SCULPT_VERTEX_NEIGHBORS_ITER_END(ni);
+        *vd.mask = max;
+        break;
+      case MASK_FILTER_SHRINK:
+        min = 1.0f;
+        SCULPT_VERTEX_NEIGHBORS_ITER_BEGIN (ss, vd.index, ni) {
+          float vmask_f = data->prev_mask[ni.index];
+          if (vmask_f < min) {
+            min = vmask_f;
+          }
+        }
+        SCULPT_VERTEX_NEIGHBORS_ITER_END(ni);
+        *vd.mask = min;
+        break;
+      case MASK_FILTER_CONTRAST_INCREASE:
+      case MASK_FILTER_CONTRAST_DECREASE:
+        delta = contrast / 2.0f;
+        gain = 1.0f - delta * 2.0f;
+        if (contrast > 0) {
+          gain = 1.0f / ((gain != 0.0f) ? gain : FLT_EPSILON);
+          offset = gain * (-delta);
+        }
+        else {
+          delta *= -1.0f;
+          offset = gain * (delta);
+        }
+        *vd.mask = gain * (*vd.mask) + offset;
+        break;
+    }
+    CLAMP(*vd.mask, 0.0f, 1.0f);
+    if (*vd.mask != prev_val) {
+      update = true;
+    }
+    if (vd.mvert) {
+      vd.mvert->flag |= ME_VERT_PBVH_UPDATE;
+    }
+  }
+  BKE_pbvh_vertex_iter_end;
+
+  if (update) {
+    BKE_pbvh_node_mark_update_mask(node);
+  }
+}
+
+static int sculpt_mask_filter_exec(bContext *C, wmOperator *op)
+{
+  ARegion *region = CTX_wm_region(C);
+  Object *ob = CTX_data_active_object(C);
+  SculptSession *ss = ob->sculpt;
+  Depsgraph *depsgraph = CTX_data_depsgraph_pointer(C);
+  PBVH *pbvh = ob->sculpt->pbvh;
+  PBVHNode **nodes;
+  Sculpt *sd = CTX_data_tool_settings(C)->sculpt;
+  int totnode;
+  int filter_type = RNA_enum_get(op->ptr, "filter_type");
+
+  BKE_sculpt_update_object_for_edit(depsgraph, ob, true, true);
+
+  SCULPT_vertex_random_access_init(ss);
+
+  if (!ob->sculpt->pmap) {
+    return OPERATOR_CANCELLED;
+  }
+
+  int num_verts = SCULPT_vertex_count_get(ss);
+
+  BKE_pbvh_search_gather(pbvh, NULL, NULL, &nodes, &totnode);
+  SCULPT_undo_push_begin("Mask filter");
+
+  for (int i = 0; i < totnode; i++) {
+    SCULPT_undo_push_node(ob, nodes[i], SCULPT_UNDO_MASK);
+  }
+
+  float *prev_mask = NULL;
+  int iterations = RNA_int_get(op->ptr, "iterations");
+
+  /* Auto iteration count calculates the number of iteration based on the vertices of the mesh to
+   * avoid adding an unnecessary amount of undo steps when using the operator from a shortcut.
+   * One iteration per 50000 vertices in the mesh should be fine in most cases.
+   * Maybe we want this to be configurable. */
+  if (RNA_boolean_get(op->ptr, "auto_iteration_count")) {
+    iterations = (int)(num_verts / 50000.0f) + 1;
+  }
+
+  for (int i = 0; i < iterations; i++) {
+    if (ELEM(filter_type, MASK_FILTER_GROW, MASK_FILTER_SHRINK)) {
+      prev_mask = MEM_mallocN(num_verts * sizeof(float), "prevmask");
+      for (int j = 0; j < num_verts; j++) {
+        prev_mask[j] = SCULPT_vertex_mask_get(ss, j);
+      }
+    }
+
+    SculptThreadedTaskData data = {
+        .sd = sd,
+        .ob = ob,
+        .nodes = nodes,
+        .filter_type = filter_type,
+        .prev_mask = prev_mask,
+    };
+
+    PBVHParallelSettings settings;
+    BKE_pbvh_parallel_range_settings(&settings, (sd->flags & SCULPT_USE_OPENMP), totnode);
+    BKE_pbvh_parallel_range(0, totnode, &data, mask_filter_task_cb, &settings);
+
+    if (ELEM(filter_type, MASK_FILTER_GROW, MASK_FILTER_SHRINK)) {
+      MEM_freeN(prev_mask);
+    }
+  }
+
+  MEM_SAFE_FREE(nodes);
+
+  SCULPT_undo_push_end();
+
+  ED_region_tag_redraw(region);
+  WM_event_add_notifier(C, NC_OBJECT | ND_DRAW, ob);
+  return OPERATOR_FINISHED;
+}
+
+void SCULPT_mask_filter_smooth_apply(Sculpt *sd, Object *ob, PBVHNode **nodes, const int totnode, const int smooth_iterations) {
+    SculptThreadedTaskData data = {
+        .sd = sd,
+        .ob = ob,
+        .nodes = nodes,
+        .filter_type = MASK_FILTER_SMOOTH,
+    };
+
+    for (int i = 0; i < smooth_iterations; i++) {
+      PBVHParallelSettings settings;
+      BKE_pbvh_parallel_range_settings(
+          &settings, (sd->flags & SCULPT_USE_OPENMP), totnode);
+      BKE_pbvh_parallel_range(0, totnode, &data, mask_filter_task_cb, &settings);
+    }
+}
+
+void SCULPT_OT_mask_filter(struct wmOperatorType *ot)
+{
+  /* Identifiers. */
+  ot->name = "Mask Filter";
+  ot->idname = "SCULPT_OT_mask_filter";
+  ot->description = "Applies a filter to modify the current mask";
+
+  /* API callbacks. */
+  ot->exec = sculpt_mask_filter_exec;
+  ot->poll = SCULPT_mode_poll;
+
+  ot->flag = OPTYPE_REGISTER;
+
+  /* RNA. */
+  RNA_def_enum(ot->srna,
+               "filter_type",
+               prop_mask_filter_types,
+               MASK_FILTER_SMOOTH,
+               "Type",
+               "Filter that is going to be applied to the mask");
+  RNA_def_int(ot->srna,
+              "iterations",
+              1,
+              1,
+              100,
+              "Iterations",
+              "Number of times that the filter is going to be applied",
+              1,
+              100);
+  RNA_def_boolean(
+      ot->srna,
+      "auto_iteration_count",
+      false,
+      "Auto Iteration Count",
+      "Use a automatic number of iterations based on the number of vertices of the sculpt");
+}
+
+static float neighbor_dirty_mask(SculptSession *ss, PBVHVertexIter *vd)
+{
+  int total = 0;
+  float avg[3];
+  zero_v3(avg);
+
+  SculptVertexNeighborIter ni;
+  SCULPT_VERTEX_NEIGHBORS_ITER_BEGIN (ss, vd->index, ni) {
+    float normalized[3];
+    sub_v3_v3v3(normalized, SCULPT_vertex_co_get(ss, ni.index), vd->co);
+    normalize_v3(normalized);
+    add_v3_v3(avg, normalized);
+    total++;
+  }
+  SCULPT_VERTEX_NEIGHBORS_ITER_END(ni);
+
+  if (total > 0) {
+    mul_v3_fl(avg, 1.0f / total);
+    float normal[3];
+    if (vd->no) {
+      normal_short_to_float_v3(normal, vd->no);
+    }
+    else {
+      copy_v3_v3(normal, vd->fno);
+    }
+    float dot = dot_v3v3(avg, normal);
+    float angle = max_ff(saacosf(dot), 0.0f);
+    return angle;
+  }
+  return 0.0f;
+}
+
+typedef struct DirtyMaskRangeData {
+  float min, max;
+} DirtyMaskRangeData;
+
+static void dirty_mask_compute_range_task_cb(void *__restrict userdata,
+                                             const int i,
+                                             const TaskParallelTLS *__restrict tls)
+{
+  SculptThreadedTaskData *data = userdata;
+  SculptSession *ss = data->ob->sculpt;
+  PBVHNode *node = data->nodes[i];
+  DirtyMaskRangeData *range = tls->userdata_chunk;
+  PBVHVertexIter vd;
+
+  BKE_pbvh_vertex_iter_begin(ss->pbvh, node, vd, PBVH_ITER_UNIQUE)
+  {
+    float dirty_mask = neighbor_dirty_mask(ss, &vd);
+    range->min = min_ff(dirty_mask, range->min);
+    range->max = max_ff(dirty_mask, range->max);
+  }
+  BKE_pbvh_vertex_iter_end;
+}
+
+static void dirty_mask_compute_range_reduce(const void *__restrict UNUSED(userdata),
+                                            void *__restrict chunk_join,
+                                            void *__restrict chunk)
+{
+  DirtyMaskRangeData *join = chunk_join;
+  DirtyMaskRangeData *range = chunk;
+  join->min = min_ff(range->min, join->min);
+  join->max = max_ff(range->max, join->max);
+}
+
+static void dirty_mask_apply_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 bool dirty_only = data->dirty_mask_dirty_only;
+  const float min = data->dirty_mask_min;
+  const float max = data->dirty_mask_max;
+
+  float range = max - min;
+  if (range < 0.0001f) {
+    range = 0.0f;
+  }
+  else {
+    range = 1.0f / range;
+  }
+
+  BKE_pbvh_vertex_iter_begin(ss->pbvh, node, vd, PBVH_ITER_UNIQUE)
+  {
+    float dirty_mask = neighbor_dirty_mask(ss, &vd);
+    float mask = *vd.mask + (1.0f - ((dirty_mask - min) * range));
+    if (dirty_only) {
+      mask = fminf(mask, 0.5f) * 2.0f;
+    }
+    *vd.mask = CLAMPIS(mask, 0.0f, 1.0f);
+
+    if (vd.mvert) {
+      vd.mvert->flag |= ME_VERT_PBVH_UPDATE;
+    }
+  }
+  BKE_pbvh_vertex_iter_end;
+  BKE_pbvh_node_mark_update_mask(node);
+}
+
+static int sculpt_dirty_mask_exec(bContext *C, wmOperator *op)
+{
+  ARegion *region = CTX_wm_region(C);
+  Object *ob = CTX_data_active_object(C);
+  SculptSession *ss = ob->sculpt;
+  Depsgraph *depsgraph = CTX_data_depsgraph_pointer(C);
+  PBVH *pbvh = ob->sculpt->pbvh;
+  PBVHNode **nodes;
+  Sculpt *sd = CTX_data_tool_settings(C)->sculpt;
+  int totnode;
+
+  BKE_sculpt_update_object_for_edit(depsgraph, ob, true, true);
+
+  SCULPT_vertex_random_access_init(ss);
+
+  if (!ob->sculpt->pmap) {
+    return OPERATOR_CANCELLED;
+  }
+
+  BKE_pbvh_search_gather(pbvh, NULL, NULL, &nodes, &totnode);
+  SCULPT_undo_push_begin("Dirty Mask");
+
+  for (int i = 0; i < totnode; i++) {
+    SCULPT_undo_push_node(ob, nodes[i], SCULPT_UNDO_MASK);
+  }
+
+  SculptThreadedTaskData data = {
+      .sd = sd,
+      .ob = ob,
+      .nodes = nodes,
+      .dirty_mask_dirty_only = RNA_boolean_get(op->ptr, "dirty_only"),
+  };
+  DirtyMaskRangeData range = {
+      .min = FLT_MAX,
+      .max = -FLT_MAX,
+  };
+
+  PBVHParallelSettings settings;
+  BKE_pbvh_parallel_range_settings(&settings, (sd->flags & SCULPT_USE_OPENMP), totnode);
+
+  settings.func_reduce = dirty_mask_compute_range_reduce;
+  settings.userdata_chunk = &range;
+  settings.userdata_chunk_size = sizeof(DirtyMaskRangeData);
+
+  BKE_pbvh_parallel_range(0, totnode, &data, dirty_mask_compute_range_task_cb, &settings);
+  data.dirty_mask_min = range.min;
+  data.dirty_mask_max = range.max;
+  BKE_pbvh_parallel_range(0, totnode, &data, dirty_mask_apply_task_cb, &settings);
+
+  MEM_SAFE_FREE(nodes);
+
+  BKE_pbvh_update_vertex_data(pbvh, PBVH_UpdateMask);
+
+  SCULPT_undo_push_end();
+
+  ED_region_tag_redraw(region);
+
+  WM_event_add_notifier(C, NC_OBJECT | ND_DRAW, ob);
+
+  return OPERATOR_FINISHED;
+}
+
+void SCULPT_OT_dirty_mask(struct wmOperatorType *ot)
+{
+  /* Identifiers. */
+  ot->name = "Dirty Mask";
+  ot->idname = "SCULPT_OT_dirty_mask";
+  ot->description = "Generates a mask based on the geometry cavity and pointiness";
+
+  /* API callbacks. */
+  ot->exec = sculpt_dirty_mask_exec;
+  ot->poll = SCULPT_mode_poll;
+
+  ot->flag = OPTYPE_REGISTER;
+
+  /* RNA. */
+  RNA_def_boolean(
+      ot->srna, "dirty_only", false, "Dirty Only", "Don't calculate cleans for convex areas");
+}
diff --git a/source/blender/editors/sculpt_paint/sculpt_filter_mesh.c b/source/blender/editors/sculpt_paint/sculpt_filter_mesh.c
index b1dd7b87507..f64e8ea609b 100644
--- a/source/blender/editors/sculpt_paint/sculpt_filter_mesh.c
+++ b/source/blender/editors/sculpt_paint/sculpt_filter_mesh.c
@@ -316,12 +316,12 @@ static void mesh_filter_task_cb(void *__restrict userdata,
       }
       case MESH_FILTER_SURFACE_SMOOTH: {
         SCULPT_surface_smooth_laplacian_step(ss,
-                                      disp,
-                                      vd.co,
-                                      ss->filter_cache->surface_smooth_laplacian_disp,
-                                      vd.index,
-                                      orig_data.co,
-                                      ss->filter_cache->surface_smooth_shape_preservation);
+                                             disp,
+                                             vd.co,
+                                             ss->filter_cache->surface_smooth_laplacian_disp,
+                                             vd.index,
+                                             orig_data.co,
+                                             ss->filter_cache->surface_smooth_shape_preservation);
         break;
       }
     }
@@ -365,11 +365,11 @@ static void mesh_filter_surface_smooth_displace_task_cb(
       continue;
     }
     SCULPT_surface_smooth_displace_step(ss,
-                                 vd.co,
-                                 ss->filter_cache->surface_smooth_laplacian_disp,
-                                 vd.index,
-                                 ss->filter_cache->surface_smooth_current_vertex,
-                                 clamp_f(fade, 0.0f, 1.0f));
+                                        vd.co,
+                                        ss->filter_cache->surface_smooth_laplacian_disp,
+                                        vd.index,
+                                        ss->filter_cache->surface_smooth_current_vertex,
+                                        clamp_f(fade, 0.0f, 1.0f));
   }
   BKE_pbvh_vertex_iter_end;
 }
diff --git a/source/blender/editors/sculpt_paint/sculpt_intern.h b/source/blender/editors/sculpt_paint/sculpt_intern.h
index 7c4142a807e..3858a990e97 100644
--- a/source/blender/editors/sculpt_paint/sculpt_intern.h
+++ b/source/blender/editors/sculpt_paint/sculpt_intern.h
@@ -82,6 +82,7 @@ void SCULPT_vertex_random_access_init(struct SculptSession *ss);
 
 int SCULPT_vertex_count_get(struct SculptSession *ss);
 const float *SCULPT_vertex_co_get(struct SculptSession *ss, int index);
+void SCULPT_vertex_normal_get(SculptSession *ss, int index, float no[3]);
 float SCULPT_vertex_mask_get(struct SculptSession *ss, int index);
 
 #define SCULPT_VERTEX_NEIGHBOR_FIXED_CAPACITY 256
@@ -132,6 +133,7 @@ void SCULPT_vertex_neighbors_get(struct SculptSession *ss,
 
 int SCULPT_active_vertex_get(SculptSession *ss);
 const float *SCULPT_active_vertex_co_get(SculptSession *ss);
+void SCULPT_active_vertex_normal_get(SculptSession *ss, float normal[3]);
 
 bool SCULPT_vertex_is_boundary(SculptSession *ss, const int index);
 
@@ -276,6 +278,9 @@ float *SCULPT_boundary_automasking_init(Object *ob,
 void SCULPT_filter_cache_init(Object *ob, Sculpt *sd);
 void SCULPT_filter_cache_free(SculptSession *ss);
 
+void SCULPT_mask_filter_smooth_apply(
+    Sculpt *sd, Object *ob, PBVHNode **nodes, const int totnode, const int smooth_iterations);
+
 /* Brushes. */
 
 /* Cloth Brush. */
@@ -839,4 +844,11 @@ void SCULPT_OT_set_pivot_position(struct wmOperatorType *ot);
 /* Mesh Filter. */
 void SCULPT_OT_mesh_filter(struct wmOperatorType *ot);
 
+/* Mask filter and Dirty Mask. */
+void SCULPT_OT_mask_filter(struct wmOperatorType *ot);
+void SCULPT_OT_dirty_mask(struct wmOperatorType *ot);
+
+/* Mask and Face Sets Expand. */
+void SCULPT_OT_mask_expand(struct wmOperatorType *ot);
+
 #endif
diff --git a/source/blender/editors/sculpt_paint/sculpt_mask_expand.c b/source/blender/editors/sculpt_paint/sculpt_mask_expand.c
new file mode 100644
index 00000000000..2d4fc2b0258
--- /dev/null
+++ b/source/blender/editors/sculpt_paint/sculpt_mask_expand.c
@@ -0,0 +1,526 @@
+/*
+ * 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) 2020 Blender Foundation.
+ * All rights reserved.
+ */
+
+/** \file
+ * \ingroup edsculpt
+ */
+
+#include "MEM_guardedalloc.h"
+
+#include "BLI_blenlib.h"
+#include "BLI_math.h"
+#include "BLI_task.h"
+
+#include "BLT_translation.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_colortools.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 "BKE_scene.h"
+
+#include "DEG_depsgraph.h"
+
+#include "WM_api.h"
+#include "WM_message.h"
+#include "WM_toolsystem.h"
+#include "WM_types.h"
+
+#include "RNA_access.h"
+#include "RNA_define.h"
+
+#include "ED_object.h"
+#include "ED_screen.h"
+#include "ED_sculpt.h"
+#include "ED_view3d.h"
+#include "paint_intern.h"
+#include "sculpt_intern.h"
+
+#include "bmesh.h"
+
+#include <math.h>
+#include <stdlib.h>
+
+
+static void sculpt_mask_expand_cancel(bContext *C, wmOperator *op)
+{
+  Object *ob = CTX_data_active_object(C);
+  SculptSession *ss = ob->sculpt;
+  const bool create_face_set = RNA_boolean_get(op->ptr, "create_face_set");
+
+  MEM_freeN(op->customdata);
+
+  for (int n = 0; n < ss->filter_cache->totnode; n++) {
+    PBVHNode *node = ss->filter_cache->nodes[n];
+    if (create_face_set) {
+      for (int i = 0; i < ss->totfaces; i++) {
+        ss->face_sets[i] = ss->filter_cache->prev_face_set[i];
+      }
+    }
+    else {
+      PBVHVertexIter vd;
+      BKE_pbvh_vertex_iter_begin(ss->pbvh, node, vd, PBVH_ITER_UNIQUE)
+      {
+        *vd.mask = ss->filter_cache->prev_mask[vd.index];
+      }
+      BKE_pbvh_vertex_iter_end;
+    }
+
+    BKE_pbvh_node_mark_redraw(node);
+  }
+
+  if (!create_face_set) {
+    SCULPT_flush_update_step(C, SCULPT_UPDATE_MASK);
+  }
+  SCULPT_filter_cache_free(ss);
+  SCULPT_undo_push_end();
+  SCULPT_flush_update_done(C, ob, SCULPT_UPDATE_MASK);
+  ED_workspace_status_text(C, NULL);
+}
+
+static void sculpt_expand_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;
+  int update_it = data->mask_expand_update_it;
+
+  BKE_pbvh_vertex_iter_begin(ss->pbvh, node, vd, PBVH_ITER_ALL)
+  {
+    int vi = vd.index;
+    float final_mask = *vd.mask;
+    if (data->mask_expand_use_normals) {
+      if (ss->filter_cache->normal_factor[SCULPT_active_vertex_get(ss)] <
+          ss->filter_cache->normal_factor[vd.index]) {
+        final_mask = 1.0f;
+      }
+      else {
+        final_mask = 0.0f;
+      }
+    }
+    else {
+      if (ss->filter_cache->mask_update_it[vi] <= update_it &&
+          ss->filter_cache->mask_update_it[vi] != 0) {
+        final_mask = 1.0f;
+      }
+      else {
+        final_mask = 0.0f;
+      }
+    }
+
+    if (data->mask_expand_create_face_set) {
+      if (final_mask == 1.0f) {
+        SCULPT_vertex_face_set_set(ss, vd.index, ss->filter_cache->new_face_set);
+      }
+      BKE_pbvh_node_mark_redraw(node);
+    }
+    else {
+
+      if (data->mask_expand_keep_prev_mask) {
+        final_mask = MAX2(ss->filter_cache->prev_mask[vd.index], final_mask);
+      }
+
+      if (data->mask_expand_invert_mask) {
+        final_mask = 1.0f - final_mask;
+      }
+
+      if (*vd.mask != final_mask) {
+        if (vd.mvert) {
+          vd.mvert->flag |= ME_VERT_PBVH_UPDATE;
+        }
+        *vd.mask = final_mask;
+        BKE_pbvh_node_mark_update_mask(node);
+      }
+    }
+  }
+  BKE_pbvh_vertex_iter_end;
+}
+
+static int sculpt_mask_expand_modal(bContext *C, wmOperator *op, const wmEvent *event)
+{
+  Depsgraph *depsgraph = CTX_data_depsgraph_pointer(C);
+  Object *ob = CTX_data_active_object(C);
+  SculptSession *ss = ob->sculpt;
+  Sculpt *sd = CTX_data_tool_settings(C)->sculpt;
+  ARegion *region = CTX_wm_region(C);
+  float prevclick_f[2];
+  copy_v2_v2(prevclick_f, op->customdata);
+  int prevclick[2] = {(int)prevclick_f[0], (int)prevclick_f[1]};
+  int len = (int)len_v2v2_int(prevclick, event->mval);
+  len = abs(len);
+  int mask_speed = RNA_int_get(op->ptr, "mask_speed");
+  int mask_expand_update_it = len / mask_speed;
+  mask_expand_update_it = mask_expand_update_it + 1;
+
+  const bool create_face_set = RNA_boolean_get(op->ptr, "create_face_set");
+
+  if (RNA_boolean_get(op->ptr, "use_cursor")) {
+    SculptCursorGeometryInfo sgi;
+    float mouse[2];
+    mouse[0] = event->mval[0];
+    mouse[1] = event->mval[1];
+    SCULPT_cursor_geometry_info_update(C, &sgi, mouse, false);
+    mask_expand_update_it = ss->filter_cache->mask_update_it[(int)SCULPT_active_vertex_get(ss)];
+  }
+
+  if ((event->type == EVT_ESCKEY && event->val == KM_PRESS) ||
+      (event->type == RIGHTMOUSE && event->val == KM_PRESS)) {
+    /* Returning OPERATOR_CANCELLED will leak memory due to not finishing
+     * undo. Better solution could be to make paint_mesh_restore_co work
+     * for this case. */
+    sculpt_mask_expand_cancel(C, op);
+    return OPERATOR_FINISHED;
+  }
+
+  if ((event->type == LEFTMOUSE && event->val == KM_RELEASE) ||
+      (event->type == EVT_RETKEY && event->val == KM_PRESS) ||
+      (event->type == EVT_PADENTER && event->val == KM_PRESS)) {
+
+    /* Smooth iterations. */
+    BKE_sculpt_update_object_for_edit(depsgraph, ob, true, false);
+    const int smooth_iterations = RNA_int_get(op->ptr, "smooth_iterations");
+    SCULPT_mask_filter_smooth_apply(sd, ob, ss->filter_cache->nodes, ss->filter_cache->totnode, smooth_iterations);
+
+    /* Pivot position. */
+    if (RNA_boolean_get(op->ptr, "update_pivot")) {
+      const char symm = sd->paint.symmetry_flags & PAINT_SYMM_AXIS_ALL;
+      const float threshold = 0.2f;
+      float avg[3];
+      int total = 0;
+      zero_v3(avg);
+
+      for (int n = 0; n < ss->filter_cache->totnode; n++) {
+        PBVHVertexIter vd;
+        BKE_pbvh_vertex_iter_begin(ss->pbvh, ss->filter_cache->nodes[n], vd, PBVH_ITER_UNIQUE)
+        {
+          const float mask = (vd.mask) ? *vd.mask : 0.0f;
+          if (mask < (0.5f + threshold) && mask > (0.5f - threshold)) {
+            if (SCULPT_check_vertex_pivot_symmetry(
+                    vd.co, ss->filter_cache->mask_expand_initial_co, symm)) {
+              add_v3_v3(avg, vd.co);
+              total++;
+            }
+          }
+        }
+        BKE_pbvh_vertex_iter_end;
+      }
+
+      if (total > 0) {
+        mul_v3_fl(avg, 1.0f / total);
+        copy_v3_v3(ss->pivot_pos, avg);
+      }
+      WM_event_add_notifier(C, NC_GEOM | ND_SELECT, ob->data);
+    }
+
+    MEM_freeN(op->customdata);
+
+    for (int i = 0; i < ss->filter_cache->totnode; i++) {
+      BKE_pbvh_node_mark_redraw(ss->filter_cache->nodes[i]);
+    }
+
+    SCULPT_filter_cache_free(ss);
+
+    SCULPT_undo_push_end();
+    SCULPT_flush_update_done(C, ob, SCULPT_UPDATE_MASK);
+    ED_workspace_status_text(C, NULL);
+    return OPERATOR_FINISHED;
+  }
+
+  /* When pressing Ctrl, expand directly to the max number of iterations. This allows to flood fill
+   * mask and face sets by connectivity directly. */
+  if (event->ctrl) {
+    mask_expand_update_it = ss->filter_cache->mask_update_last_it - 1;
+  }
+
+  if (!ELEM(event->type, MOUSEMOVE, EVT_LEFTCTRLKEY, EVT_RIGHTCTRLKEY)) {
+    return OPERATOR_RUNNING_MODAL;
+  }
+
+  if (mask_expand_update_it == ss->filter_cache->mask_update_current_it) {
+    ED_region_tag_redraw(region);
+    return OPERATOR_RUNNING_MODAL;
+  }
+
+  if (mask_expand_update_it < ss->filter_cache->mask_update_last_it) {
+
+    if (create_face_set) {
+      for (int i = 0; i < ss->totfaces; i++) {
+        ss->face_sets[i] = ss->filter_cache->prev_face_set[i];
+      }
+    }
+    SculptThreadedTaskData data = {
+        .sd = sd,
+        .ob = ob,
+        .nodes = ss->filter_cache->nodes,
+        .mask_expand_update_it = mask_expand_update_it,
+        .mask_expand_use_normals = RNA_boolean_get(op->ptr, "use_normals"),
+        .mask_expand_invert_mask = RNA_boolean_get(op->ptr, "invert"),
+        .mask_expand_keep_prev_mask = RNA_boolean_get(op->ptr, "keep_previous_mask"),
+        .mask_expand_create_face_set = RNA_boolean_get(op->ptr, "create_face_set"),
+    };
+    PBVHParallelSettings settings;
+    BKE_pbvh_parallel_range_settings(
+        &settings, (sd->flags & SCULPT_USE_OPENMP), ss->filter_cache->totnode);
+    BKE_pbvh_parallel_range(0, ss->filter_cache->totnode, &data, sculpt_expand_task_cb, &settings);
+    ss->filter_cache->mask_update_current_it = mask_expand_update_it;
+  }
+
+  SCULPT_flush_update_step(C, SCULPT_UPDATE_MASK);
+
+  return OPERATOR_RUNNING_MODAL;
+}
+
+typedef struct MaskExpandFloodFillData {
+  float original_normal[3];
+  float edge_sensitivity;
+  bool use_normals;
+} MaskExpandFloodFillData;
+
+static bool mask_expand_floodfill_cb(
+    SculptSession *ss, int from_v, int to_v, bool is_duplicate, void *userdata)
+{
+  MaskExpandFloodFillData *data = userdata;
+
+  if (!is_duplicate) {
+    int to_it = ss->filter_cache->mask_update_it[from_v] + 1;
+    ss->filter_cache->mask_update_it[to_v] = to_it;
+    if (to_it > ss->filter_cache->mask_update_last_it) {
+      ss->filter_cache->mask_update_last_it = to_it;
+    }
+
+    if (data->use_normals) {
+      float current_normal[3], prev_normal[3];
+      SCULPT_vertex_normal_get(ss, to_v, current_normal);
+      SCULPT_vertex_normal_get(ss, from_v, prev_normal);
+      const float from_edge_factor = ss->filter_cache->edge_factor[from_v];
+      ss->filter_cache->edge_factor[to_v] = dot_v3v3(current_normal, prev_normal) *
+                                            from_edge_factor;
+      ss->filter_cache->normal_factor[to_v] = dot_v3v3(data->original_normal, current_normal) *
+                                              powf(from_edge_factor, data->edge_sensitivity);
+      CLAMP(ss->filter_cache->normal_factor[to_v], 0.0f, 1.0f);
+    }
+  }
+  else {
+    /* PBVH_GRIDS duplicate handling. */
+    ss->filter_cache->mask_update_it[to_v] = ss->filter_cache->mask_update_it[from_v];
+    if (data->use_normals) {
+      ss->filter_cache->edge_factor[to_v] = ss->filter_cache->edge_factor[from_v];
+      ss->filter_cache->normal_factor[to_v] = ss->filter_cache->normal_factor[from_v];
+    }
+  }
+
+  return true;
+}
+
+static int sculpt_mask_expand_invoke(bContext *C, wmOperator *op, const wmEvent *event)
+{
+  Depsgraph *depsgraph = CTX_data_depsgraph_pointer(C);
+  Object *ob = CTX_data_active_object(C);
+  SculptSession *ss = ob->sculpt;
+  Sculpt *sd = CTX_data_tool_settings(C)->sculpt;
+  PBVH *pbvh = ob->sculpt->pbvh;
+
+  const bool use_normals = RNA_boolean_get(op->ptr, "use_normals");
+  const bool create_face_set = RNA_boolean_get(op->ptr, "create_face_set");
+
+  SculptCursorGeometryInfo sgi;
+  float mouse[2];
+  mouse[0] = event->mval[0];
+  mouse[1] = event->mval[1];
+
+  SCULPT_vertex_random_access_init(ss);
+
+  op->customdata = MEM_mallocN(2 * sizeof(float), "initial mouse position");
+  copy_v2_v2(op->customdata, mouse);
+
+  SCULPT_cursor_geometry_info_update(C, &sgi, mouse, false);
+
+  BKE_sculpt_update_object_for_edit(depsgraph, ob, true, true);
+
+  int vertex_count = SCULPT_vertex_count_get(ss);
+
+  ss->filter_cache = MEM_callocN(sizeof(FilterCache), "filter cache");
+
+  BKE_pbvh_search_gather(pbvh, NULL, NULL, &ss->filter_cache->nodes, &ss->filter_cache->totnode);
+
+  SCULPT_undo_push_begin("Mask Expand");
+
+  if (create_face_set) {
+    SCULPT_undo_push_node(ob, ss->filter_cache->nodes[0], SCULPT_UNDO_FACE_SETS);
+    for (int i = 0; i < ss->filter_cache->totnode; i++) {
+      BKE_pbvh_node_mark_redraw(ss->filter_cache->nodes[i]);
+    }
+  }
+  else {
+    for (int i = 0; i < ss->filter_cache->totnode; i++) {
+      SCULPT_undo_push_node(ob, ss->filter_cache->nodes[i], SCULPT_UNDO_MASK);
+      BKE_pbvh_node_mark_redraw(ss->filter_cache->nodes[i]);
+    }
+  }
+
+  ss->filter_cache->mask_update_it = MEM_callocN(sizeof(int) * vertex_count,
+                                                 "mask update iteration");
+  if (use_normals) {
+    ss->filter_cache->normal_factor = MEM_callocN(sizeof(float) * vertex_count,
+                                                  "mask update normal factor");
+    ss->filter_cache->edge_factor = MEM_callocN(sizeof(float) * vertex_count,
+                                                "mask update normal factor");
+    for (int i = 0; i < vertex_count; i++) {
+      ss->filter_cache->edge_factor[i] = 1.0f;
+    }
+  }
+
+  if (create_face_set) {
+    ss->filter_cache->prev_face_set = MEM_callocN(sizeof(float) * ss->totfaces, "prev face mask");
+    for (int i = 0; i < ss->totfaces; i++) {
+      ss->filter_cache->prev_face_set[i] = ss->face_sets[i];
+    }
+    ss->filter_cache->new_face_set = SCULPT_face_set_next_available_get(ss);
+  }
+  else {
+    ss->filter_cache->prev_mask = MEM_callocN(sizeof(float) * vertex_count, "prev mask");
+    for (int i = 0; i < vertex_count; i++) {
+      ss->filter_cache->prev_mask[i] = SCULPT_vertex_mask_get(ss, i);
+    }
+  }
+
+  ss->filter_cache->mask_update_last_it = 1;
+  ss->filter_cache->mask_update_current_it = 1;
+  ss->filter_cache->mask_update_it[SCULPT_active_vertex_get(ss)] = 0;
+
+  copy_v3_v3(ss->filter_cache->mask_expand_initial_co, SCULPT_active_vertex_co_get(ss));
+
+  SculptFloodFill flood;
+  SCULPT_floodfill_init(ss, &flood);
+  SCULPT_floodfill_add_active(sd, ob, ss, &flood, FLT_MAX);
+
+  MaskExpandFloodFillData fdata = {
+      .use_normals = use_normals,
+      .edge_sensitivity = RNA_int_get(op->ptr, "edge_sensitivity"),
+  };
+  SCULPT_active_vertex_normal_get(ss, fdata.original_normal);
+  SCULPT_floodfill_execute(ss, &flood, mask_expand_floodfill_cb, &fdata);
+  SCULPT_floodfill_free(&flood);
+
+  if (use_normals) {
+    for (int repeat = 0; repeat < 2; repeat++) {
+      for (int i = 0; i < vertex_count; i++) {
+        float avg = 0.0f;
+        SculptVertexNeighborIter ni;
+        SCULPT_VERTEX_NEIGHBORS_ITER_BEGIN (ss, i, ni) {
+          avg += ss->filter_cache->normal_factor[ni.index];
+        }
+        SCULPT_VERTEX_NEIGHBORS_ITER_END(ni);
+        ss->filter_cache->normal_factor[i] = avg / ni.size;
+      }
+    }
+
+    MEM_SAFE_FREE(ss->filter_cache->edge_factor);
+  }
+
+  SculptThreadedTaskData data = {
+      .sd = sd,
+      .ob = ob,
+      .nodes = ss->filter_cache->nodes,
+      .mask_expand_update_it = 0,
+      .mask_expand_use_normals = RNA_boolean_get(op->ptr, "use_normals"),
+      .mask_expand_invert_mask = RNA_boolean_get(op->ptr, "invert"),
+      .mask_expand_keep_prev_mask = RNA_boolean_get(op->ptr, "keep_previous_mask"),
+      .mask_expand_create_face_set = RNA_boolean_get(op->ptr, "create_face_set"),
+  };
+  PBVHParallelSettings settings;
+  BKE_pbvh_parallel_range_settings(
+      &settings, (sd->flags & SCULPT_USE_OPENMP), ss->filter_cache->totnode);
+  BKE_pbvh_parallel_range(0, ss->filter_cache->totnode, &data, sculpt_expand_task_cb, &settings);
+
+  const char *status_str = TIP_(
+      "Move the mouse to expand the mask from the active vertex. LMB: confirm mask, ESC/RMB: "
+      "cancel");
+  ED_workspace_status_text(C, status_str);
+
+  SCULPT_flush_update_step(C, SCULPT_UPDATE_MASK);
+  WM_event_add_modal_handler(C, op);
+  return OPERATOR_RUNNING_MODAL;
+}
+
+void SCULPT_OT_mask_expand(wmOperatorType *ot)
+{
+  /* Identifiers. */
+  ot->name = "Mask Expand";
+  ot->idname = "SCULPT_OT_mask_expand";
+  ot->description = "Expands a mask from the initial active vertex under the cursor";
+
+  /* API callbacks. */
+  ot->invoke = sculpt_mask_expand_invoke;
+  ot->modal = sculpt_mask_expand_modal;
+  ot->cancel = sculpt_mask_expand_cancel;
+  ot->poll = SCULPT_mode_poll;
+
+  ot->flag = OPTYPE_REGISTER | OPTYPE_UNDO;
+  ot->prop = RNA_def_boolean(ot->srna, "invert", true, "Invert", "Invert the new mask");
+  ot->prop = RNA_def_boolean(
+      ot->srna, "use_cursor", true, "Use Cursor", "Expand the mask to the cursor position");
+  ot->prop = RNA_def_boolean(ot->srna,
+                             "update_pivot",
+                             true,
+                             "Update Pivot Position",
+                             "Set the pivot position to the mask border after creating the mask");
+  ot->prop = RNA_def_int(ot->srna, "smooth_iterations", 2, 0, 10, "Smooth iterations", "", 0, 10);
+  ot->prop = RNA_def_int(ot->srna, "mask_speed", 5, 1, 10, "Mask speed", "", 1, 10);
+
+  ot->prop = RNA_def_boolean(ot->srna,
+                             "use_normals",
+                             true,
+                             "Use Normals",
+                             "Generate the mask using the normals and curvature of the model");
+  ot->prop = RNA_def_boolean(ot->srna,
+                             "keep_previous_mask",
+                             false,
+                             "Keep Previous Mask",
+                             "Generate the new mask on top of the current one");
+  ot->prop = RNA_def_int(ot->srna,
+                         "edge_sensitivity",
+                         300,
+                         0,
+                         2000,
+                         "Edge Detection Sensitivity",
+                         "Sensitivity for expanding the mask across sculpted sharp edges when "
+                         "using normals to generate the mask",
+                         0,
+                         2000);
+  ot->prop = RNA_def_boolean(ot->srna,
+                             "create_face_set",
+                             false,
+                             "Expand Face Mask",
+                             "Expand a new Face Mask instead of the sculpt mask");
+}
diff --git a/source/blender/editors/sculpt_paint/sculpt_smooth.c b/source/blender/editors/sculpt_paint/sculpt_smooth.c
index 0f629320333..de3211abe08 100644
--- a/source/blender/editors/sculpt_paint/sculpt_smooth.c
+++ b/source/blender/editors/sculpt_paint/sculpt_smooth.c
@@ -62,8 +62,6 @@
 #include <math.h>
 #include <stdlib.h>
 
-
-
 /* For the smooth brush, uses the neighboring vertices around vert to calculate
  * a smoothed location for vert. Skips corner vertices (used by only one
  * polygon). */
@@ -185,7 +183,8 @@ void SCULPT_bmesh_four_neighbor_average(float avg[3], float direction[3], BMVert
   }
 }
 
-/* Generic functions for laplacian smoothing. These functions do not take boundary vertices into account. */
+/* Generic functions for laplacian smoothing. These functions do not take boundary vertices into
+ * account. */
 
 void SCULPT_neighbor_coords_average(SculptSession *ss, float result[3], int index)
 {
@@ -498,9 +497,8 @@ void SCULPT_surface_smooth_displace_step(SculptSession *ss,
   }
 }
 
-static void SCULPT_do_surface_smooth_brush_laplacian_task_cb_ex(void *__restrict userdata,
-                                                         const int n,
-                                                         const TaskParallelTLS *__restrict tls)
+static void SCULPT_do_surface_smooth_brush_laplacian_task_cb_ex(
+    void *__restrict userdata, const int n, const TaskParallelTLS *__restrict tls)
 {
   SculptThreadedTaskData *data = userdata;
   SculptSession *ss = data->ob->sculpt;
@@ -528,21 +526,20 @@ static void SCULPT_do_surface_smooth_brush_laplacian_task_cb_ex(void *__restrict
 
       float disp[3];
       SCULPT_surface_smooth_laplacian_step(ss,
-                                    disp,
-                                    vd.co,
-                                    ss->cache->surface_smooth_laplacian_disp,
-                                    vd.index,
-                                    orig_data.co,
-                                    alpha);
+                                           disp,
+                                           vd.co,
+                                           ss->cache->surface_smooth_laplacian_disp,
+                                           vd.index,
+                                           orig_data.co,
+                                           alpha);
       madd_v3_v3fl(vd.co, disp, clamp_f(fade, 0.0f, 1.0f));
     }
     BKE_pbvh_vertex_iter_end;
   }
 }
 
-static void SCULPT_do_surface_smooth_brush_displace_task_cb_ex(void *__restrict userdata,
-                                                        const int n,
-                                                        const TaskParallelTLS *__restrict tls)
+static void SCULPT_do_surface_smooth_brush_displace_task_cb_ex(
+    void *__restrict userdata, const int n, const TaskParallelTLS *__restrict tls)
 {
   SculptThreadedTaskData *data = userdata;
   SculptSession *ss = data->ob->sculpt;
@@ -599,5 +596,3 @@ void SCULPT_do_surface_smooth_brush(Sculpt *sd, Object *ob, PBVHNode **nodes, in
         0, totnode, &data, SCULPT_do_surface_smooth_brush_displace_task_cb_ex, &settings);
   }
 }
-
-