Sculpt: Smooth deform type for Boundary Brush

This adds a smooth deformation type to the boundary brush, which smooths
the boundary and has a regular falloff towards the inside of the mesh.
For smoothing, only vertices parallel to the boundary are taken into
account, creating this effect.

Reviewed By: sergey

Differential Revision: https://developer.blender.org/D9204

1 files changed, 63 insertions, 0 deletions

diff --git a/source/blender/editors/sculpt_paint/sculpt_boundary.c b/source/blender/editors/sculpt_paint/sculpt_boundary.c
index ce8b63ce4f8..84f2721c31a 100644
--- a/source/blender/editors/sculpt_paint/sculpt_boundary.c
+++ b/source/blender/editors/sculpt_paint/sculpt_boundary.c
@@ -868,6 +868,66 @@ static void do_boundary_brush_twist_task_cb_ex(void *__restrict userdata,
   BKE_pbvh_vertex_iter_end;
 }
 
+static void do_boundary_brush_smooth_task_cb_ex(void *__restrict userdata,
+                                                const int n,
+                                                const TaskParallelTLS *__restrict UNUSED(tls))
+{
+  SculptThreadedTaskData *data = userdata;
+  SculptSession *ss = data->ob->sculpt;
+  const int symmetry_pass = ss->cache->mirror_symmetry_pass;
+  const SculptBoundary *boundary = ss->cache->boundaries[symmetry_pass];
+  const ePaintSymmetryFlags symm = SCULPT_mesh_symmetry_xyz_get(data->ob);
+  const Brush *brush = data->brush;
+
+  const float strength = ss->cache->bstrength;
+
+  PBVHVertexIter vd;
+  SculptOrigVertData orig_data;
+  SCULPT_orig_vert_data_init(&orig_data, data->ob, data->nodes[n]);
+
+  BKE_pbvh_vertex_iter_begin(ss->pbvh, data->nodes[n], vd, PBVH_ITER_UNIQUE)
+  {
+    if (boundary->edit_info[vd.index].num_propagation_steps == -1) {
+      continue;
+    }
+
+    SCULPT_orig_vert_data_update(&orig_data, &vd);
+    if (!SCULPT_check_vertex_pivot_symmetry(
+            orig_data.co, boundary->initial_vertex_position, symm)) {
+      continue;
+    }
+
+    float coord_accum[3] = {0.0f, 0.0f, 0.0f};
+    int total_neighbors = 0;
+    const int current_propagation_steps = boundary->edit_info[vd.index].num_propagation_steps;
+    SculptVertexNeighborIter ni;
+    SCULPT_VERTEX_NEIGHBORS_ITER_BEGIN (ss, vd.index, ni) {
+      if (current_propagation_steps == boundary->edit_info[ni.index].num_propagation_steps) {
+        add_v3_v3(coord_accum, SCULPT_vertex_co_get(ss, ni.index));
+        total_neighbors++;
+      }
+    }
+    SCULPT_VERTEX_NEIGHBORS_ITER_END(ni);
+
+    if (total_neighbors == 0) {
+      continue;
+    }
+    float disp[3];
+    float avg[3];
+    const float mask = vd.mask ? 1.0f - *vd.mask : 1.0f;
+    mul_v3_v3fl(avg, coord_accum, 1.0f / total_neighbors);
+    sub_v3_v3v3(disp, avg, vd.co);
+    float *target_co = SCULPT_brush_deform_target_vertex_co_get(ss, brush->deform_target, &vd);
+    madd_v3_v3v3fl(
+        target_co, vd.co, disp, boundary->edit_info[vd.index].strength_factor * mask * strength);
+
+    if (vd.mvert) {
+      vd.mvert->flag |= ME_VERT_PBVH_UPDATE;
+    }
+  }
+  BKE_pbvh_vertex_iter_end;
+}
+
 /* Main Brush Function. */
 void SCULPT_do_boundary_brush(Sculpt *sd, Object *ob, PBVHNode **nodes, int totnode)
 {
@@ -945,6 +1005,9 @@ void SCULPT_do_boundary_brush(Sculpt *sd, Object *ob, PBVHNode **nodes, int totn
     case BRUSH_BOUNDARY_DEFORM_TWIST:
       BLI_task_parallel_range(0, totnode, &data, do_boundary_brush_twist_task_cb_ex, &settings);
       break;
+    case BRUSH_BOUNDARY_DEFORM_SMOOTH:
+      BLI_task_parallel_range(0, totnode, &data, do_boundary_brush_smooth_task_cb_ex, &settings);
+      break;
   }
 }