Cleanup: Move Multiplane Scrape brush to its own file

5 files changed, 504 insertions, 428 deletions

diff --git a/source/blender/editors/sculpt_paint/CMakeLists.txt b/source/blender/editors/sculpt_paint/CMakeLists.txt
index 1f568250f3f..f497b80e0f4 100644
--- a/source/blender/editors/sculpt_paint/CMakeLists.txt
+++ b/source/blender/editors/sculpt_paint/CMakeLists.txt
@@ -59,6 +59,7 @@ set(SRC
   paint_vertex_weight_ops.c
   paint_vertex_weight_utils.c
   sculpt.c
+  sculpt_multiplane_scrape.c
   sculpt_cloth.c
   sculpt_pose.c
   sculpt_undo.c
diff --git a/source/blender/editors/sculpt_paint/paint_cursor.c b/source/blender/editors/sculpt_paint/paint_cursor.c
index 963fc556827..07dfa970404 100644
--- a/source/blender/editors/sculpt_paint/paint_cursor.c
+++ b/source/blender/editors/sculpt_paint/paint_cursor.c
@@ -1223,70 +1223,6 @@ static void sculpt_geometry_preview_lines_draw(const uint gpuattr, SculptSession
   }
 }
 
-static void sculpt_multiplane_scrape_preview_draw(const uint gpuattr,
-                                                  SculptSession *ss,
-                                                  const float outline_col[3],
-                                                  const float outline_alpha)
-{
-  float local_mat_inv[4][4];
-  invert_m4_m4(local_mat_inv, ss->cache->stroke_local_mat);
-  GPU_matrix_mul(local_mat_inv);
-  float angle = ss->cache->multiplane_scrape_angle;
-  if (ss->cache->pen_flip || ss->cache->invert) {
-    angle = -angle;
-  }
-
-  float offset = ss->cache->radius * 0.25f;
-
-  float p[3] = {0.0f, 0.0f, ss->cache->radius};
-  float y_axis[3] = {0.0f, 1.0f, 0.0f};
-  float p_l[3];
-  float p_r[3];
-  float area_center[3] = {0.0f, 0.0f, 0.0f};
-  rotate_v3_v3v3fl(p_r, p, y_axis, DEG2RADF((angle + 180) * 0.5f));
-  rotate_v3_v3v3fl(p_l, p, y_axis, DEG2RADF(-(angle + 180) * 0.5f));
-
-  immBegin(GPU_PRIM_LINES, 14);
-  immVertex3f(gpuattr, area_center[0], area_center[1] + offset, area_center[2]);
-  immVertex3f(gpuattr, p_r[0], p_r[1] + offset, p_r[2]);
-  immVertex3f(gpuattr, area_center[0], area_center[1] + offset, area_center[2]);
-  immVertex3f(gpuattr, p_l[0], p_l[1] + offset, p_l[2]);
-
-  immVertex3f(gpuattr, area_center[0], area_center[1] - offset, area_center[2]);
-  immVertex3f(gpuattr, p_r[0], p_r[1] - offset, p_r[2]);
-  immVertex3f(gpuattr, area_center[0], area_center[1] - offset, area_center[2]);
-  immVertex3f(gpuattr, p_l[0], p_l[1] - offset, p_l[2]);
-
-  immVertex3f(gpuattr, area_center[0], area_center[1] - offset, area_center[2]);
-  immVertex3f(gpuattr, area_center[0], area_center[1] + offset, area_center[2]);
-
-  immVertex3f(gpuattr, p_r[0], p_r[1] - offset, p_r[2]);
-  immVertex3f(gpuattr, p_r[0], p_r[1] + offset, p_r[2]);
-
-  immVertex3f(gpuattr, p_l[0], p_l[1] - offset, p_l[2]);
-  immVertex3f(gpuattr, p_l[0], p_l[1] + offset, p_l[2]);
-
-  immEnd();
-
-  immUniformColor3fvAlpha(outline_col, outline_alpha * 0.1f);
-  immBegin(GPU_PRIM_TRIS, 12);
-  immVertex3f(gpuattr, area_center[0], area_center[1] + offset, area_center[2]);
-  immVertex3f(gpuattr, p_r[0], p_r[1] + offset, p_r[2]);
-  immVertex3f(gpuattr, p_r[0], p_r[1] - offset, p_r[2]);
-  immVertex3f(gpuattr, area_center[0], area_center[1] + offset, area_center[2]);
-  immVertex3f(gpuattr, area_center[0], area_center[1] - offset, area_center[2]);
-  immVertex3f(gpuattr, p_r[0], p_r[1] - offset, p_r[2]);
-
-  immVertex3f(gpuattr, area_center[0], area_center[1] + offset, area_center[2]);
-  immVertex3f(gpuattr, p_l[0], p_l[1] + offset, p_l[2]);
-  immVertex3f(gpuattr, p_l[0], p_l[1] - offset, p_l[2]);
-  immVertex3f(gpuattr, area_center[0], area_center[1] + offset, area_center[2]);
-  immVertex3f(gpuattr, area_center[0], area_center[1] - offset, area_center[2]);
-  immVertex3f(gpuattr, p_l[0], p_l[1] - offset, p_l[2]);
-
-  immEnd();
-}
-
 static bool paint_use_2d_cursor(ePaintMode mode)
 {
   if (mode >= PAINT_MODE_TEXTURE_3D) {
@@ -1629,7 +1565,7 @@ static void paint_draw_cursor(bContext *C, int x, int y, void *UNUSED(unused))
                                       NULL);
             GPU_matrix_push();
             GPU_matrix_mul(vc.obact->obmat);
-            sculpt_multiplane_scrape_preview_draw(pos, ss, outline_col, outline_alpha);
+            SCULPT_multiplane_scrape_preview_draw(pos, ss, outline_col, outline_alpha);
             GPU_matrix_pop();
             GPU_matrix_pop_projection();
           }
diff --git a/source/blender/editors/sculpt_paint/sculpt.c b/source/blender/editors/sculpt_paint/sculpt.c
index dcbcdc98ddf..3f60d96b7ce 100644
--- a/source/blender/editors/sculpt_paint/sculpt.c
+++ b/source/blender/editors/sculpt_paint/sculpt.c
@@ -1897,7 +1897,7 @@ static void calc_area_center(
   }
 }
 
-static void calc_area_normal(
+void SCULPT_calc_area_normal(
     Sculpt *sd, Object *ob, PBVHNode **nodes, int totnode, float r_area_no[3])
 {
   const Brush *brush = BKE_paint_brush(&sd->paint);
@@ -2413,7 +2413,7 @@ static void calc_sculpt_normal(
       break;
 
     case SCULPT_DISP_DIR_AREA:
-      calc_area_normal(sd, ob, nodes, totnode, r_area_no);
+      SCULPT_calc_area_normal(sd, ob, nodes, totnode, r_area_no);
       break;
 
     default:
@@ -4690,7 +4690,7 @@ static void do_inflate_brush(Sculpt *sd, Object *ob, PBVHNode **nodes, int totno
   BKE_pbvh_parallel_range(0, totnode, &data, do_inflate_brush_task_cb_ex, &settings);
 }
 
-static int plane_trim(const StrokeCache *cache, const Brush *brush, const float val[3])
+int SCULPT_plane_trim(const StrokeCache *cache, const Brush *brush, const float val[3])
 {
   return (!(brush->flag & BRUSH_PLANE_TRIM) ||
           ((dot_v3v3(val, val) <= cache->radius_squared * cache->plane_trim_squared)));
@@ -4705,13 +4705,13 @@ static bool plane_point_side_flip(const float co[3], const float plane[4], const
   return d <= 0.0f;
 }
 
-static int plane_point_side(const float co[3], const float plane[4])
+int SCULPT_plane_point_side(const float co[3], const float plane[4])
 {
   float d = plane_point_side_v3(plane, co);
   return d <= 0.0f;
 }
 
-static float get_offset(Sculpt *sd, SculptSession *ss)
+float SCULPT_brush_plane_offset_get(Sculpt *sd, SculptSession *ss)
 {
   Brush *brush = BKE_paint_brush(&sd->paint);
 
@@ -4756,7 +4756,7 @@ static void do_flatten_brush_task_cb_ex(void *__restrict userdata,
 
       sub_v3_v3v3(val, intr, vd.co);
 
-      if (plane_trim(ss->cache, brush, val)) {
+      if (SCULPT_plane_trim(ss->cache, brush, val)) {
         const float fade = bstrength * SCULPT_brush_strength_factor(ss,
                                                                     brush,
                                                                     vd.co,
@@ -4788,7 +4788,7 @@ static void do_flatten_brush(Sculpt *sd, Object *ob, PBVHNode **nodes, int totno
   float area_no[3];
   float area_co[3];
 
-  float offset = get_offset(sd, ss);
+  float offset = SCULPT_brush_plane_offset_get(sd, ss);
   float displace;
   float temp[3];
 
@@ -4944,7 +4944,7 @@ static void do_clay_brush(Sculpt *sd, Object *ob, PBVHNode **nodes, int totnode)
   const float initial_radius = fabsf(ss->cache->initial_radius);
   bool flip = ss->cache->bstrength < 0.0f;
 
-  float offset = get_offset(sd, ss);
+  float offset = SCULPT_brush_plane_offset_get(sd, ss);
   float displace;
 
   float area_no[3];
@@ -5001,349 +5001,6 @@ static void do_clay_brush(Sculpt *sd, Object *ob, PBVHNode **nodes, int totnode)
   BKE_pbvh_parallel_range(0, totnode, &data, do_clay_brush_task_cb_ex, &settings);
 }
 
-/* -------------------------------------------------------------------- */
-
-/** \name Sculpt Multiplane Scrape Brush
- * \{ */
-
-typedef struct MultiplaneScrapeSampleData {
-  float area_cos[2][3];
-  float area_nos[2][3];
-  int area_count[2];
-} MultiplaneScrapeSampleData;
-
-static void calc_multiplane_scrape_surface_task_cb(void *__restrict userdata,
-                                                   const int n,
-                                                   const TaskParallelTLS *__restrict tls)
-{
-  SculptThreadedTaskData *data = userdata;
-  SculptSession *ss = data->ob->sculpt;
-  const Brush *brush = data->brush;
-  MultiplaneScrapeSampleData *mssd = tls->userdata_chunk;
-  float(*mat)[4] = data->mat;
-
-  PBVHVertexIter vd;
-
-  SculptBrushTest test;
-  SculptBrushTestFn sculpt_brush_test_sq_fn = SCULPT_brush_test_init_with_falloff_shape(
-      ss, &test, brush->falloff_shape);
-
-  /* Apply the brush normal radius to the test before sampling. */
-  float test_radius = sqrtf(test.radius_squared);
-  test_radius *= brush->normal_radius_factor;
-  test.radius_squared = test_radius * test_radius;
-
-  BKE_pbvh_vertex_iter_begin(ss->pbvh, data->nodes[n], vd, PBVH_ITER_UNIQUE)
-  {
-
-    if (sculpt_brush_test_sq_fn(&test, vd.co)) {
-      float local_co[3];
-      float normal[3];
-      if (vd.no) {
-        normal_short_to_float_v3(normal, vd.no);
-      }
-      else {
-        copy_v3_v3(normal, vd.fno);
-      }
-      mul_v3_m4v3(local_co, mat, vd.co);
-      /* Use the brush falloff to weight the sampled normals. */
-      const float fade = SCULPT_brush_strength_factor(ss,
-                                                      brush,
-                                                      vd.co,
-                                                      sqrtf(test.dist),
-                                                      vd.no,
-                                                      vd.fno,
-                                                      vd.mask ? *vd.mask : 0.0f,
-                                                      vd.index,
-                                                      tls->thread_id);
-
-      /* Sample the normal and area of the +X and -X axis individually. */
-      if (local_co[0] > 0.0f) {
-        madd_v3_v3fl(mssd->area_nos[0], normal, fade);
-        add_v3_v3(mssd->area_cos[0], vd.co);
-        mssd->area_count[0]++;
-      }
-      else {
-        madd_v3_v3fl(mssd->area_nos[1], normal, fade);
-        add_v3_v3(mssd->area_cos[1], vd.co);
-        mssd->area_count[1]++;
-      }
-    }
-    BKE_pbvh_vertex_iter_end;
-  }
-}
-
-static void calc_multiplane_scrape_surface_reduce(const void *__restrict UNUSED(userdata),
-                                                  void *__restrict chunk_join,
-                                                  void *__restrict chunk)
-{
-  MultiplaneScrapeSampleData *join = chunk_join;
-  MultiplaneScrapeSampleData *mssd = chunk;
-
-  add_v3_v3(join->area_cos[0], mssd->area_cos[0]);
-  add_v3_v3(join->area_cos[1], mssd->area_cos[1]);
-
-  add_v3_v3(join->area_nos[0], mssd->area_nos[0]);
-  add_v3_v3(join->area_nos[1], mssd->area_nos[1]);
-
-  join->area_count[0] += mssd->area_count[0];
-  join->area_count[1] += mssd->area_count[1];
-}
-
-static void do_multiplane_scrape_brush_task_cb_ex(void *__restrict userdata,
-                                                  const int n,
-                                                  const TaskParallelTLS *__restrict tls)
-{
-  SculptThreadedTaskData *data = userdata;
-  SculptSession *ss = data->ob->sculpt;
-  const Brush *brush = data->brush;
-  float(*mat)[4] = data->mat;
-  float(*scrape_planes)[4] = data->multiplane_scrape_planes;
-
-  float angle = data->multiplane_scrape_angle;
-
-  PBVHVertexIter vd;
-  float(*proxy)[3];
-  const float bstrength = fabsf(ss->cache->bstrength);
-
-  proxy = BKE_pbvh_node_add_proxy(ss->pbvh, data->nodes[n])->co;
-
-  SculptBrushTest test;
-  SculptBrushTestFn sculpt_brush_test_sq_fn = SCULPT_brush_test_init_with_falloff_shape(
-      ss, &test, data->brush->falloff_shape);
-
-  BKE_pbvh_vertex_iter_begin(ss->pbvh, data->nodes[n], vd, PBVH_ITER_UNIQUE)
-  {
-
-    if (sculpt_brush_test_sq_fn(&test, vd.co)) {
-      float local_co[3];
-      bool deform = false;
-
-      mul_v3_m4v3(local_co, mat, vd.co);
-
-      if (local_co[0] > 0.0f) {
-        deform = !plane_point_side(vd.co, scrape_planes[0]);
-      }
-      else {
-        deform = !plane_point_side(vd.co, scrape_planes[1]);
-      }
-
-      if (angle < 0.0f) {
-        deform = true;
-      }
-
-      if (deform) {
-        float intr[3];
-        float val[3];
-
-        if (local_co[0] > 0.0f) {
-          closest_to_plane_normalized_v3(intr, scrape_planes[0], vd.co);
-        }
-        else {
-          closest_to_plane_normalized_v3(intr, scrape_planes[1], vd.co);
-        }
-
-        sub_v3_v3v3(val, intr, vd.co);
-        if (plane_trim(ss->cache, brush, val)) {
-          /* Deform the local space along the Y axis to avoid artifacts on curved strokes. */
-          /* This produces a not round brush tip. */
-          local_co[1] *= 2.0f;
-          const float fade = bstrength * SCULPT_brush_strength_factor(ss,
-                                                                      brush,
-                                                                      vd.co,
-                                                                      len_v3(local_co),
-                                                                      vd.no,
-                                                                      vd.fno,
-                                                                      vd.mask ? *vd.mask : 0.0f,
-                                                                      vd.index,
-                                                                      tls->thread_id);
-
-          mul_v3_v3fl(proxy[vd.i], val, fade);
-
-          if (vd.mvert) {
-            vd.mvert->flag |= ME_VERT_PBVH_UPDATE;
-          }
-        }
-      }
-    }
-  }
-  BKE_pbvh_vertex_iter_end;
-}
-
-static void do_multiplane_scrape_brush(Sculpt *sd, Object *ob, PBVHNode **nodes, int totnode)
-{
-  SculptSession *ss = ob->sculpt;
-  Brush *brush = BKE_paint_brush(&sd->paint);
-
-  const bool flip = (ss->cache->bstrength < 0.0f);
-  const float radius = flip ? -ss->cache->radius : ss->cache->radius;
-  const float offset = get_offset(sd, ss);
-  const float displace = -radius * offset;
-
-  /* The sculpt-plane normal (whatever its set to) */
-  float area_no_sp[3];
-
-  /* Geometry normal. */
-  float area_no[3];
-  float area_co[3];
-
-  float temp[3];
-  float mat[4][4];
-
-  SCULPT_calc_brush_plane(sd, ob, nodes, totnode, area_no_sp, area_co);
-
-  if (brush->sculpt_plane != SCULPT_DISP_DIR_AREA || (brush->flag & BRUSH_ORIGINAL_NORMAL)) {
-    calc_area_normal(sd, ob, nodes, totnode, area_no);
-  }
-  else {
-    copy_v3_v3(area_no, area_no_sp);
-  }
-
-  /* Delay the first daub because grab delta is not setup. */
-  if (ss->cache->first_time) {
-    ss->cache->multiplane_scrape_angle = 0.0f;
-    return;
-  }
-
-  if (is_zero_v3(ss->cache->grab_delta_symmetry)) {
-    return;
-  }
-
-  mul_v3_v3v3(temp, area_no_sp, ss->cache->scale);
-  mul_v3_fl(temp, displace);
-  add_v3_v3(area_co, temp);
-
-  /* Init brush local space matrix. */
-  cross_v3_v3v3(mat[0], area_no, ss->cache->grab_delta_symmetry);
-  mat[0][3] = 0.0f;
-  cross_v3_v3v3(mat[1], area_no, mat[0]);
-  mat[1][3] = 0.0f;
-  copy_v3_v3(mat[2], area_no);
-  mat[2][3] = 0.0f;
-  copy_v3_v3(mat[3], ss->cache->location);
-  mat[3][3] = 1.0f;
-  normalize_m4(mat);
-  invert_m4(mat);
-
-  /* Update matrix for the cursor preview. */
-  if (ss->cache->mirror_symmetry_pass == 0 && ss->cache->radial_symmetry_pass == 0) {
-    copy_m4_m4(ss->cache->stroke_local_mat, mat);
-  }
-
-  /* Dynamic mode. */
-
-  if (brush->flag2 & BRUSH_MULTIPLANE_SCRAPE_DYNAMIC) {
-    /* Sample the individual normal and area center of the two areas at both sides of the cursor.
-     */
-    SculptThreadedTaskData sample_data = {
-        .sd = NULL,
-        .ob = ob,
-        .brush = brush,
-        .nodes = nodes,
-        .totnode = totnode,
-        .mat = mat,
-    };
-
-    MultiplaneScrapeSampleData mssd = {{{0}}};
-
-    PBVHParallelSettings sample_settings;
-    BKE_pbvh_parallel_range_settings(&sample_settings, (sd->flags & SCULPT_USE_OPENMP), totnode);
-    sample_settings.func_reduce = calc_multiplane_scrape_surface_reduce;
-    sample_settings.userdata_chunk = &mssd;
-    sample_settings.userdata_chunk_size = sizeof(MultiplaneScrapeSampleData);
-
-    BKE_pbvh_parallel_range(
-        0, totnode, &sample_data, calc_multiplane_scrape_surface_task_cb, &sample_settings);
-
-    float sampled_plane_normals[2][3];
-    float sampled_plane_co[2][3];
-    float sampled_cv[2][3];
-    float mid_co[3];
-
-    /* Use the area center of both planes to detect if we are sculpting along a concave or convex
-     * edge. */
-    mul_v3_v3fl(sampled_plane_co[0], mssd.area_cos[0], 1.0f / (float)mssd.area_count[0]);
-    mul_v3_v3fl(sampled_plane_co[1], mssd.area_cos[1], 1.0f / (float)mssd.area_count[1]);
-    mid_v3_v3v3(mid_co, sampled_plane_co[0], sampled_plane_co[1]);
-
-    /* Calculate the scrape planes angle based on the sampled normals. */
-    mul_v3_v3fl(sampled_plane_normals[0], mssd.area_nos[0], 1.0f / (float)mssd.area_count[0]);
-    mul_v3_v3fl(sampled_plane_normals[1], mssd.area_nos[1], 1.0f / (float)mssd.area_count[1]);
-    normalize_v3(sampled_plane_normals[0]);
-    normalize_v3(sampled_plane_normals[1]);
-
-    float sampled_angle = angle_v3v3(sampled_plane_normals[0], sampled_plane_normals[1]);
-    copy_v3_v3(sampled_cv[0], area_no);
-    sub_v3_v3v3(sampled_cv[1], ss->cache->location, mid_co);
-
-    sampled_angle += DEG2RADF(brush->multiplane_scrape_angle) * ss->cache->pressure;
-
-    /* Invert the angle if we are sculpting along a concave edge. */
-    if (dot_v3v3(sampled_cv[0], sampled_cv[1]) < 0.0f) {
-      sampled_angle = -sampled_angle;
-    }
-
-    /* In dynamic mode, set the angle to 0 when inverting the brush, so you can trim plane
-     * surfaces without changing the brush. */
-    if (flip) {
-      sampled_angle = 0.0f;
-    }
-    else {
-      copy_v3_v3(area_co, ss->cache->location);
-    }
-
-    /* Interpolate between the previous and new sampled angles to avoid artifacts when if angle
-     * difference between two samples is too big. */
-    ss->cache->multiplane_scrape_angle = interpf(
-        RAD2DEGF(sampled_angle), ss->cache->multiplane_scrape_angle, 0.2f);
-  }
-  else {
-
-    /* Standard mode: Scrape with the brush property fixed angle. */
-    copy_v3_v3(area_co, ss->cache->location);
-    ss->cache->multiplane_scrape_angle = brush->multiplane_scrape_angle;
-    if (flip) {
-      ss->cache->multiplane_scrape_angle *= -1.0f;
-    }
-  }
-
-  SculptThreadedTaskData data = {
-      .sd = sd,
-      .ob = ob,
-      .brush = brush,
-      .nodes = nodes,
-      .mat = mat,
-      .multiplane_scrape_angle = ss->cache->multiplane_scrape_angle,
-  };
-
-  /* Calculate the final left and right scrape planes. */
-  float plane_no[3];
-  float plane_no_rot[3];
-  float y_axis[3] = {0.0f, 1.0f, 0.0f};
-  float mat_inv[4][4];
-  invert_m4_m4(mat_inv, mat);
-
-  mul_v3_mat3_m4v3(plane_no, mat, area_no);
-  rotate_v3_v3v3fl(
-      plane_no_rot, plane_no, y_axis, DEG2RADF(-ss->cache->multiplane_scrape_angle * 0.5f));
-  mul_v3_mat3_m4v3(plane_no, mat_inv, plane_no_rot);
-  normalize_v3(plane_no);
-  plane_from_point_normal_v3(data.multiplane_scrape_planes[1], area_co, plane_no);
-
-  mul_v3_mat3_m4v3(plane_no, mat, area_no);
-  rotate_v3_v3v3fl(
-      plane_no_rot, plane_no, y_axis, DEG2RADF(ss->cache->multiplane_scrape_angle * 0.5f));
-  mul_v3_mat3_m4v3(plane_no, mat_inv, plane_no_rot);
-  normalize_v3(plane_no);
-  plane_from_point_normal_v3(data.multiplane_scrape_planes[0], area_co, plane_no);
-
-  PBVHParallelSettings settings;
-  BKE_pbvh_parallel_range_settings(&settings, (sd->flags & SCULPT_USE_OPENMP), totnode);
-  BKE_pbvh_parallel_range(0, totnode, &data, do_multiplane_scrape_brush_task_cb_ex, &settings);
-}
-
-/** \} */
-
 static void do_clay_strips_brush_task_cb_ex(void *__restrict userdata,
                                             const int n,
                                             const TaskParallelTLS *__restrict tls)
@@ -5377,7 +5034,7 @@ static void do_clay_strips_brush_task_cb_ex(void *__restrict userdata,
 
         sub_v3_v3v3(val, intr, vd.co);
 
-        if (plane_trim(ss->cache, brush, val)) {
+        if (SCULPT_plane_trim(ss->cache, brush, val)) {
           /* The normal from the vertices is ignored, it causes glitch with planes, see: T44390. */
           const float fade = bstrength *
                              SCULPT_brush_strength_factor(ss,
@@ -5409,7 +5066,7 @@ static void do_clay_strips_brush(Sculpt *sd, Object *ob, PBVHNode **nodes, int t
 
   const bool flip = (ss->cache->bstrength < 0.0f);
   const float radius = flip ? -ss->cache->radius : ss->cache->radius;
-  const float offset = get_offset(sd, ss);
+  const float offset = SCULPT_brush_plane_offset_get(sd, ss);
   const float displace = radius * (0.25f + offset);
 
   /* The sculpt-plane normal (whatever its set to). */
@@ -5427,7 +5084,7 @@ static void do_clay_strips_brush(Sculpt *sd, Object *ob, PBVHNode **nodes, int t
   SCULPT_calc_brush_plane(sd, ob, nodes, totnode, area_no_sp, area_co);
 
   if (brush->sculpt_plane != SCULPT_DISP_DIR_AREA || (brush->flag & BRUSH_ORIGINAL_NORMAL)) {
-    calc_area_normal(sd, ob, nodes, totnode, area_no);
+    SCULPT_calc_area_normal(sd, ob, nodes, totnode, area_no);
   }
   else {
     copy_v3_v3(area_no, area_no_sp);
@@ -5502,7 +5159,7 @@ static void do_fill_brush_task_cb_ex(void *__restrict userdata,
   BKE_pbvh_vertex_iter_begin(ss->pbvh, data->nodes[n], vd, PBVH_ITER_UNIQUE)
   {
     if (sculpt_brush_test_sq_fn(&test, vd.co)) {
-      if (plane_point_side(vd.co, test.plane_tool)) {
+      if (SCULPT_plane_point_side(vd.co, test.plane_tool)) {
         float intr[3];
         float val[3];
 
@@ -5510,7 +5167,7 @@ static void do_fill_brush_task_cb_ex(void *__restrict userdata,
 
         sub_v3_v3v3(val, intr, vd.co);
 
-        if (plane_trim(ss->cache, brush, val)) {
+        if (SCULPT_plane_trim(ss->cache, brush, val)) {
           const float fade = bstrength * SCULPT_brush_strength_factor(ss,
                                                                       brush,
                                                                       vd.co,
@@ -5542,7 +5199,7 @@ static void do_fill_brush(Sculpt *sd, Object *ob, PBVHNode **nodes, int totnode)
 
   float area_no[3];
   float area_co[3];
-  float offset = get_offset(sd, ss);
+  float offset = SCULPT_brush_plane_offset_get(sd, ss);
 
   float displace;
 
@@ -5594,7 +5251,7 @@ static void do_scrape_brush_task_cb_ex(void *__restrict userdata,
   BKE_pbvh_vertex_iter_begin(ss->pbvh, data->nodes[n], vd, PBVH_ITER_UNIQUE)
   {
     if (sculpt_brush_test_sq_fn(&test, vd.co)) {
-      if (!plane_point_side(vd.co, test.plane_tool)) {
+      if (!SCULPT_plane_point_side(vd.co, test.plane_tool)) {
         float intr[3];
         float val[3];
 
@@ -5602,7 +5259,7 @@ static void do_scrape_brush_task_cb_ex(void *__restrict userdata,
 
         sub_v3_v3v3(val, intr, vd.co);
 
-        if (plane_trim(ss->cache, brush, val)) {
+        if (SCULPT_plane_trim(ss->cache, brush, val)) {
           const float fade = bstrength * SCULPT_brush_strength_factor(ss,
                                                                       brush,
                                                                       vd.co,
@@ -5634,7 +5291,7 @@ static void do_scrape_brush(Sculpt *sd, Object *ob, PBVHNode **nodes, int totnod
 
   float area_no[3];
   float area_co[3];
-  float offset = get_offset(sd, ss);
+  float offset = SCULPT_brush_plane_offset_get(sd, ss);
 
   float displace;
 
@@ -5754,7 +5411,7 @@ static void do_clay_thumb_brush(Sculpt *sd, Object *ob, PBVHNode **nodes, int to
   Brush *brush = BKE_paint_brush(&sd->paint);
 
   const float radius = ss->cache->radius;
-  const float offset = get_offset(sd, ss);
+  const float offset = SCULPT_brush_plane_offset_get(sd, ss);
   const float displace = radius * (0.25f + offset);
 
   /* Sampled geometry normal and area center. */
@@ -5770,7 +5427,7 @@ static void do_clay_thumb_brush(Sculpt *sd, Object *ob, PBVHNode **nodes, int to
   SCULPT_calc_brush_plane(sd, ob, nodes, totnode, area_no_sp, area_co);
 
   if (brush->sculpt_plane != SCULPT_DISP_DIR_AREA || (brush->flag & BRUSH_ORIGINAL_NORMAL)) {
-    calc_area_normal(sd, ob, nodes, totnode, area_no);
+    SCULPT_calc_area_normal(sd, ob, nodes, totnode, area_no);
   }
   else {
     copy_v3_v3(area_no, area_no_sp);
@@ -6161,7 +5818,7 @@ static void do_brush_action(Sculpt *sd, Object *ob, Brush *brush, UnifiedPaintSe
         do_clay_strips_brush(sd, ob, nodes, totnode);
         break;
       case SCULPT_TOOL_MULTIPLANE_SCRAPE:
-        do_multiplane_scrape_brush(sd, ob, nodes, totnode);
+        SCULPT_do_multiplane_scrape_brush(sd, ob, nodes, totnode);
         break;
       case SCULPT_TOOL_CLAY_THUMB:
         do_clay_thumb_brush(sd, ob, nodes, totnode);
diff --git a/source/blender/editors/sculpt_paint/sculpt_intern.h b/source/blender/editors/sculpt_paint/sculpt_intern.h
index e65b7404558..612908edfa1 100644
--- a/source/blender/editors/sculpt_paint/sculpt_intern.h
+++ b/source/blender/editors/sculpt_paint/sculpt_intern.h
@@ -155,12 +155,23 @@ void SCULPT_calc_brush_plane(struct Sculpt *sd,
                              int totnode,
                              float r_area_no[3],
                              float r_area_co[3]);
+
+void SCULPT_calc_area_normal(
+    Sculpt *sd, Object *ob, PBVHNode **nodes, int totnode, float r_area_no[3]);
+
 int SCULPT_nearest_vertex_get(struct Sculpt *sd,
                               struct Object *ob,
                               const float co[3],
                               float max_distance,
                               bool use_original);
 
+int SCULPT_plane_point_side(const float co[3], const float plane[4]);
+int SCULPT_plane_trim(const struct StrokeCache *cache,
+                      const struct Brush *brush,
+                      const float val[3]);
+
+float SCULPT_brush_plane_offset_get(Sculpt *sd, SculptSession *ss);
+
 ePaintSymmetryAreas SCULPT_get_vertex_symm_area(const float co[3]);
 bool SCULPT_check_vertex_pivot_symmetry(const float vco[3], const float pco[3], const char symm);
 bool SCULPT_is_symmetry_iteration_valid(char i, char symm);
@@ -239,6 +250,13 @@ struct SculptPoseIKChain *SCULPT_pose_ik_chain_init(struct Sculpt *sd,
                                                     const float radius);
 void SCULPT_pose_ik_chain_free(struct SculptPoseIKChain *ik_chain);
 
+/* Multiplane Scrape Brush. */
+void SCULPT_do_multiplane_scrape_brush(Sculpt *sd, Object *ob, PBVHNode **nodes, int totnode);
+void SCULPT_multiplane_scrape_preview_draw(const uint gpuattr,
+                                           SculptSession *ss,
+                                           const float outline_col[3],
+                                           const float outline_alpha);
+
 /* Sculpt Visibility API */
 void SCULPT_visibility_sync_all_face_sets_to_vertices(struct SculptSession *ss);
 void SCULPT_visibility_sync_all_vertex_to_face_sets(struct SculptSession *ss);
diff --git a/source/blender/editors/sculpt_paint/sculpt_multiplane_scrape.c b/source/blender/editors/sculpt_paint/sculpt_multiplane_scrape.c
new file mode 100644
index 00000000000..038d0e5a08c
--- /dev/null
+++ b/source/blender/editors/sculpt_paint/sculpt_multiplane_scrape.c
@@ -0,0 +1,464 @@
+/*
+ * 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_math.h"
+#include "BLI_blenlib.h"
+#include "BLI_task.h"
+
+#include "DNA_mesh_types.h"
+#include "DNA_meshdata_types.h"
+#include "DNA_object_types.h"
+#include "DNA_brush_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 "paint_intern.h"
+#include "sculpt_intern.h"
+
+#include "GPU_draw.h"
+#include "GPU_immediate.h"
+#include "GPU_immediate_util.h"
+#include "GPU_matrix.h"
+#include "GPU_state.h"
+
+#include "bmesh.h"
+
+#include <math.h>
+#include <stdlib.h>
+
+
+typedef struct MultiplaneScrapeSampleData {
+  float area_cos[2][3];
+  float area_nos[2][3];
+  int area_count[2];
+} MultiplaneScrapeSampleData;
+
+static void calc_multiplane_scrape_surface_task_cb(void *__restrict userdata,
+                                                   const int n,
+                                                   const TaskParallelTLS *__restrict tls)
+{
+  SculptThreadedTaskData *data = userdata;
+  SculptSession *ss = data->ob->sculpt;
+  const Brush *brush = data->brush;
+  MultiplaneScrapeSampleData *mssd = tls->userdata_chunk;
+  float(*mat)[4] = data->mat;
+
+  PBVHVertexIter vd;
+
+  SculptBrushTest test;
+  SculptBrushTestFn sculpt_brush_test_sq_fn = SCULPT_brush_test_init_with_falloff_shape(
+      ss, &test, brush->falloff_shape);
+
+  /* Apply the brush normal radius to the test before sampling. */
+  float test_radius = sqrtf(test.radius_squared);
+  test_radius *= brush->normal_radius_factor;
+  test.radius_squared = test_radius * test_radius;
+
+  BKE_pbvh_vertex_iter_begin(ss->pbvh, data->nodes[n], vd, PBVH_ITER_UNIQUE)
+  {
+
+    if (sculpt_brush_test_sq_fn(&test, vd.co)) {
+      float local_co[3];
+      float normal[3];
+      if (vd.no) {
+        normal_short_to_float_v3(normal, vd.no);
+      }
+      else {
+        copy_v3_v3(normal, vd.fno);
+      }
+      mul_v3_m4v3(local_co, mat, vd.co);
+      /* Use the brush falloff to weight the sampled normals. */
+      const float fade = SCULPT_brush_strength_factor(ss,
+                                                      brush,
+                                                      vd.co,
+                                                      sqrtf(test.dist),
+                                                      vd.no,
+                                                      vd.fno,
+                                                      vd.mask ? *vd.mask : 0.0f,
+                                                      vd.index,
+                                                      tls->thread_id);
+
+      /* Sample the normal and area of the +X and -X axis individually. */
+      if (local_co[0] > 0.0f) {
+        madd_v3_v3fl(mssd->area_nos[0], normal, fade);
+        add_v3_v3(mssd->area_cos[0], vd.co);
+        mssd->area_count[0]++;
+      }
+      else {
+        madd_v3_v3fl(mssd->area_nos[1], normal, fade);
+        add_v3_v3(mssd->area_cos[1], vd.co);
+        mssd->area_count[1]++;
+      }
+    }
+    BKE_pbvh_vertex_iter_end;
+  }
+}
+
+static void calc_multiplane_scrape_surface_reduce(const void *__restrict UNUSED(userdata),
+                                                  void *__restrict chunk_join,
+                                                  void *__restrict chunk)
+{
+  MultiplaneScrapeSampleData *join = chunk_join;
+  MultiplaneScrapeSampleData *mssd = chunk;
+
+  add_v3_v3(join->area_cos[0], mssd->area_cos[0]);
+  add_v3_v3(join->area_cos[1], mssd->area_cos[1]);
+
+  add_v3_v3(join->area_nos[0], mssd->area_nos[0]);
+  add_v3_v3(join->area_nos[1], mssd->area_nos[1]);
+
+  join->area_count[0] += mssd->area_count[0];
+  join->area_count[1] += mssd->area_count[1];
+}
+
+static void do_multiplane_scrape_brush_task_cb_ex(void *__restrict userdata,
+                                                  const int n,
+                                                  const TaskParallelTLS *__restrict tls)
+{
+  SculptThreadedTaskData *data = userdata;
+  SculptSession *ss = data->ob->sculpt;
+  const Brush *brush = data->brush;
+  float(*mat)[4] = data->mat;
+  float(*scrape_planes)[4] = data->multiplane_scrape_planes;
+
+  float angle = data->multiplane_scrape_angle;
+
+  PBVHVertexIter vd;
+  float(*proxy)[3];
+  const float bstrength = fabsf(ss->cache->bstrength);
+
+  proxy = BKE_pbvh_node_add_proxy(ss->pbvh, data->nodes[n])->co;
+
+  SculptBrushTest test;
+  SculptBrushTestFn sculpt_brush_test_sq_fn = SCULPT_brush_test_init_with_falloff_shape(
+      ss, &test, data->brush->falloff_shape);
+
+  BKE_pbvh_vertex_iter_begin(ss->pbvh, data->nodes[n], vd, PBVH_ITER_UNIQUE)
+  {
+
+    if (sculpt_brush_test_sq_fn(&test, vd.co)) {
+      float local_co[3];
+      bool deform = false;
+
+      mul_v3_m4v3(local_co, mat, vd.co);
+
+      if (local_co[0] > 0.0f) {
+        deform = !SCULPT_plane_point_side(vd.co, scrape_planes[0]);
+      }
+      else {
+        deform = !SCULPT_plane_point_side(vd.co, scrape_planes[1]);
+      }
+
+      if (angle < 0.0f) {
+        deform = true;
+      }
+
+      if (deform) {
+        float intr[3];
+        float val[3];
+
+        if (local_co[0] > 0.0f) {
+          closest_to_plane_normalized_v3(intr, scrape_planes[0], vd.co);
+        }
+        else {
+          closest_to_plane_normalized_v3(intr, scrape_planes[1], vd.co);
+        }
+
+        sub_v3_v3v3(val, intr, vd.co);
+        if (SCULPT_plane_trim(ss->cache, brush, val)) {
+          /* Deform the local space along the Y axis to avoid artifacts on curved strokes. */
+          /* This produces a not round brush tip. */
+          local_co[1] *= 2.0f;
+          const float fade = bstrength * SCULPT_brush_strength_factor(ss,
+                                                                      brush,
+                                                                      vd.co,
+                                                                      len_v3(local_co),
+                                                                      vd.no,
+                                                                      vd.fno,
+                                                                      vd.mask ? *vd.mask : 0.0f,
+                                                                      vd.index,
+                                                                      tls->thread_id);
+
+          mul_v3_v3fl(proxy[vd.i], val, fade);
+
+          if (vd.mvert) {
+            vd.mvert->flag |= ME_VERT_PBVH_UPDATE;
+          }
+        }
+      }
+    }
+  }
+  BKE_pbvh_vertex_iter_end;
+}
+
+
+/* Public functions. */
+
+/* Main Brush Function. */
+void SCULPT_do_multiplane_scrape_brush(Sculpt *sd, Object *ob, PBVHNode **nodes, int totnode)
+{
+  SculptSession *ss = ob->sculpt;
+  Brush *brush = BKE_paint_brush(&sd->paint);
+
+  const bool flip = (ss->cache->bstrength < 0.0f);
+  const float radius = flip ? -ss->cache->radius : ss->cache->radius;
+  const float offset = SCULPT_brush_plane_offset_get(sd, ss);
+  const float displace = -radius * offset;
+
+  /* The sculpt-plane normal (whatever its set to) */
+  float area_no_sp[3];
+
+  /* Geometry normal. */
+  float area_no[3];
+  float area_co[3];
+
+  float temp[3];
+  float mat[4][4];
+
+  SCULPT_calc_brush_plane(sd, ob, nodes, totnode, area_no_sp, area_co);
+
+  if (brush->sculpt_plane != SCULPT_DISP_DIR_AREA || (brush->flag & BRUSH_ORIGINAL_NORMAL)) {
+    SCULPT_calc_area_normal(sd, ob, nodes, totnode, area_no);
+  }
+  else {
+    copy_v3_v3(area_no, area_no_sp);
+  }
+
+  /* Delay the first daub because grab delta is not setup. */
+  if (ss->cache->first_time) {
+    ss->cache->multiplane_scrape_angle = 0.0f;
+    return;
+  }
+
+  if (is_zero_v3(ss->cache->grab_delta_symmetry)) {
+    return;
+  }
+
+  mul_v3_v3v3(temp, area_no_sp, ss->cache->scale);
+  mul_v3_fl(temp, displace);
+  add_v3_v3(area_co, temp);
+
+  /* Init brush local space matrix. */
+  cross_v3_v3v3(mat[0], area_no, ss->cache->grab_delta_symmetry);
+  mat[0][3] = 0.0f;
+  cross_v3_v3v3(mat[1], area_no, mat[0]);
+  mat[1][3] = 0.0f;
+  copy_v3_v3(mat[2], area_no);
+  mat[2][3] = 0.0f;
+  copy_v3_v3(mat[3], ss->cache->location);
+  mat[3][3] = 1.0f;
+  normalize_m4(mat);
+  invert_m4(mat);
+
+  /* Update matrix for the cursor preview. */
+  if (ss->cache->mirror_symmetry_pass == 0 && ss->cache->radial_symmetry_pass == 0) {
+    copy_m4_m4(ss->cache->stroke_local_mat, mat);
+  }
+
+  /* Dynamic mode. */
+
+  if (brush->flag2 & BRUSH_MULTIPLANE_SCRAPE_DYNAMIC) {
+    /* Sample the individual normal and area center of the two areas at both sides of the cursor.
+     */
+    SculptThreadedTaskData sample_data = {
+        .sd = NULL,
+        .ob = ob,
+        .brush = brush,
+        .nodes = nodes,
+        .totnode = totnode,
+        .mat = mat,
+    };
+
+    MultiplaneScrapeSampleData mssd = {{{0}}};
+
+    PBVHParallelSettings sample_settings;
+    BKE_pbvh_parallel_range_settings(&sample_settings, (sd->flags & SCULPT_USE_OPENMP), totnode);
+    sample_settings.func_reduce = calc_multiplane_scrape_surface_reduce;
+    sample_settings.userdata_chunk = &mssd;
+    sample_settings.userdata_chunk_size = sizeof(MultiplaneScrapeSampleData);
+
+    BKE_pbvh_parallel_range(
+        0, totnode, &sample_data, calc_multiplane_scrape_surface_task_cb, &sample_settings);
+
+    float sampled_plane_normals[2][3];
+    float sampled_plane_co[2][3];
+    float sampled_cv[2][3];
+    float mid_co[3];
+
+    /* Use the area center of both planes to detect if we are sculpting along a concave or convex
+     * edge. */
+    mul_v3_v3fl(sampled_plane_co[0], mssd.area_cos[0], 1.0f / (float)mssd.area_count[0]);
+    mul_v3_v3fl(sampled_plane_co[1], mssd.area_cos[1], 1.0f / (float)mssd.area_count[1]);
+    mid_v3_v3v3(mid_co, sampled_plane_co[0], sampled_plane_co[1]);
+
+    /* Calculate the scrape planes angle based on the sampled normals. */
+    mul_v3_v3fl(sampled_plane_normals[0], mssd.area_nos[0], 1.0f / (float)mssd.area_count[0]);
+    mul_v3_v3fl(sampled_plane_normals[1], mssd.area_nos[1], 1.0f / (float)mssd.area_count[1]);
+    normalize_v3(sampled_plane_normals[0]);
+    normalize_v3(sampled_plane_normals[1]);
+
+    float sampled_angle = angle_v3v3(sampled_plane_normals[0], sampled_plane_normals[1]);
+    copy_v3_v3(sampled_cv[0], area_no);
+    sub_v3_v3v3(sampled_cv[1], ss->cache->location, mid_co);
+
+    sampled_angle += DEG2RADF(brush->multiplane_scrape_angle) * ss->cache->pressure;
+
+    /* Invert the angle if we are sculpting along a concave edge. */
+    if (dot_v3v3(sampled_cv[0], sampled_cv[1]) < 0.0f) {
+      sampled_angle = -sampled_angle;
+    }
+
+    /* In dynamic mode, set the angle to 0 when inverting the brush, so you can trim plane
+     * surfaces without changing the brush. */
+    if (flip) {
+      sampled_angle = 0.0f;
+    }
+    else {
+      copy_v3_v3(area_co, ss->cache->location);
+    }
+
+    /* Interpolate between the previous and new sampled angles to avoid artifacts when if angle
+     * difference between two samples is too big. */
+    ss->cache->multiplane_scrape_angle = interpf(
+        RAD2DEGF(sampled_angle), ss->cache->multiplane_scrape_angle, 0.2f);
+  }
+  else {
+
+    /* Standard mode: Scrape with the brush property fixed angle. */
+    copy_v3_v3(area_co, ss->cache->location);
+    ss->cache->multiplane_scrape_angle = brush->multiplane_scrape_angle;
+    if (flip) {
+      ss->cache->multiplane_scrape_angle *= -1.0f;
+    }
+  }
+
+  SculptThreadedTaskData data = {
+      .sd = sd,
+      .ob = ob,
+      .brush = brush,
+      .nodes = nodes,
+      .mat = mat,
+      .multiplane_scrape_angle = ss->cache->multiplane_scrape_angle,
+  };
+
+  /* Calculate the final left and right scrape planes. */
+  float plane_no[3];
+  float plane_no_rot[3];
+  float y_axis[3] = {0.0f, 1.0f, 0.0f};
+  float mat_inv[4][4];
+  invert_m4_m4(mat_inv, mat);
+
+  mul_v3_mat3_m4v3(plane_no, mat, area_no);
+  rotate_v3_v3v3fl(
+      plane_no_rot, plane_no, y_axis, DEG2RADF(-ss->cache->multiplane_scrape_angle * 0.5f));
+  mul_v3_mat3_m4v3(plane_no, mat_inv, plane_no_rot);
+  normalize_v3(plane_no);
+  plane_from_point_normal_v3(data.multiplane_scrape_planes[1], area_co, plane_no);
+
+  mul_v3_mat3_m4v3(plane_no, mat, area_no);
+  rotate_v3_v3v3fl(
+      plane_no_rot, plane_no, y_axis, DEG2RADF(ss->cache->multiplane_scrape_angle * 0.5f));
+  mul_v3_mat3_m4v3(plane_no, mat_inv, plane_no_rot);
+  normalize_v3(plane_no);
+  plane_from_point_normal_v3(data.multiplane_scrape_planes[0], area_co, plane_no);
+
+  PBVHParallelSettings settings;
+  BKE_pbvh_parallel_range_settings(&settings, (sd->flags & SCULPT_USE_OPENMP), totnode);
+  BKE_pbvh_parallel_range(0, totnode, &data, do_multiplane_scrape_brush_task_cb_ex, &settings);
+}
+
+void SCULPT_multiplane_scrape_preview_draw(const uint gpuattr,
+                                                  SculptSession *ss,
+                                                  const float outline_col[3],
+                                                  const float outline_alpha)
+{
+  float local_mat_inv[4][4];
+  invert_m4_m4(local_mat_inv, ss->cache->stroke_local_mat);
+  GPU_matrix_mul(local_mat_inv);
+  float angle = ss->cache->multiplane_scrape_angle;
+  if (ss->cache->pen_flip || ss->cache->invert) {
+    angle = -angle;
+  }
+
+  float offset = ss->cache->radius * 0.25f;
+
+  float p[3] = {0.0f, 0.0f, ss->cache->radius};
+  float y_axis[3] = {0.0f, 1.0f, 0.0f};
+  float p_l[3];
+  float p_r[3];
+  float area_center[3] = {0.0f, 0.0f, 0.0f};
+  rotate_v3_v3v3fl(p_r, p, y_axis, DEG2RADF((angle + 180) * 0.5f));
+  rotate_v3_v3v3fl(p_l, p, y_axis, DEG2RADF(-(angle + 180) * 0.5f));
+
+  immBegin(GPU_PRIM_LINES, 14);
+  immVertex3f(gpuattr, area_center[0], area_center[1] + offset, area_center[2]);
+  immVertex3f(gpuattr, p_r[0], p_r[1] + offset, p_r[2]);
+  immVertex3f(gpuattr, area_center[0], area_center[1] + offset, area_center[2]);
+  immVertex3f(gpuattr, p_l[0], p_l[1] + offset, p_l[2]);
+
+  immVertex3f(gpuattr, area_center[0], area_center[1] - offset, area_center[2]);
+  immVertex3f(gpuattr, p_r[0], p_r[1] - offset, p_r[2]);
+  immVertex3f(gpuattr, area_center[0], area_center[1] - offset, area_center[2]);
+  immVertex3f(gpuattr, p_l[0], p_l[1] - offset, p_l[2]);
+
+  immVertex3f(gpuattr, area_center[0], area_center[1] - offset, area_center[2]);
+  immVertex3f(gpuattr, area_center[0], area_center[1] + offset, area_center[2]);
+
+  immVertex3f(gpuattr, p_r[0], p_r[1] - offset, p_r[2]);
+  immVertex3f(gpuattr, p_r[0], p_r[1] + offset, p_r[2]);
+
+  immVertex3f(gpuattr, p_l[0], p_l[1] - offset, p_l[2]);
+  immVertex3f(gpuattr, p_l[0], p_l[1] + offset, p_l[2]);
+
+  immEnd();
+
+  immUniformColor3fvAlpha(outline_col, outline_alpha * 0.1f);
+  immBegin(GPU_PRIM_TRIS, 12);
+  immVertex3f(gpuattr, area_center[0], area_center[1] + offset, area_center[2]);
+  immVertex3f(gpuattr, p_r[0], p_r[1] + offset, p_r[2]);
+  immVertex3f(gpuattr, p_r[0], p_r[1] - offset, p_r[2]);
+  immVertex3f(gpuattr, area_center[0], area_center[1] + offset, area_center[2]);
+  immVertex3f(gpuattr, area_center[0], area_center[1] - offset, area_center[2]);
+  immVertex3f(gpuattr, p_r[0], p_r[1] - offset, p_r[2]);
+
+  immVertex3f(gpuattr, area_center[0], area_center[1] + offset, area_center[2]);
+  immVertex3f(gpuattr, p_l[0], p_l[1] + offset, p_l[2]);
+  immVertex3f(gpuattr, p_l[0], p_l[1] - offset, p_l[2]);
+  immVertex3f(gpuattr, area_center[0], area_center[1] + offset, area_center[2]);
+  immVertex3f(gpuattr, area_center[0], area_center[1] - offset, area_center[2]);
+  immVertex3f(gpuattr, p_l[0], p_l[1] - offset, p_l[2]);
+
+  immEnd();
+}