Sculpt: Location option for lasso trim and depth info

This adds a location option to the trim lasso tool to position the shape
in the middle of the volume of the object instead of in the surface
under the cursor.

{F9349724}

In order to make this work, the SCULPT_cursor_geometry_info_update can
now also get the depth of the geometry from the raycast. The depth is
calculated as the second further intersecting triangle in the raycast
over the entire mesh. This information will also be used to improve and
create new tools.

Differential Revision: https://developer.blender.org/D9622

1 files changed, 43 insertions, 4 deletions

diff --git a/source/blender/editors/sculpt_paint/paint_mask.c b/source/blender/editors/sculpt_paint/paint_mask.c
index 17d13041f28..b3e5687a6e5 100644
--- a/source/blender/editors/sculpt_paint/paint_mask.c
+++ b/source/blender/editors/sculpt_paint/paint_mask.c
@@ -949,6 +949,24 @@ static EnumPropertyItem prop_trim_orientation_types[] = {
     {0, NULL, 0, NULL, NULL},
 };
 
+typedef enum eSculptTrimLocationType {
+  SCULPT_GESTURE_TRIM_LOCATION_DEPTH_SURFACE,
+  SCULPT_GESTURE_TRIM_LOCATION_DEPTH_VOLUME,
+} eSculptTrimLocationType;
+static EnumPropertyItem prop_trim_location_types[] = {
+    {SCULPT_GESTURE_TRIM_LOCATION_DEPTH_SURFACE,
+     "DEPTH_SURFACE",
+     0,
+     "Surface",
+     "Use the surface under the cursor to locate the trimming shape"},
+    {SCULPT_GESTURE_TRIM_LOCATION_DEPTH_VOLUME,
+     "DEPTH_VOLUME",
+     0,
+     "Volume",
+     "Use the volume of the mesh to locate the trimming shape in the center of the volume"},
+    {0, NULL, 0, NULL, NULL},
+};
+
 typedef struct SculptGestureTrimOperation {
   SculptGestureOperation op;
 
@@ -962,6 +980,7 @@ typedef struct SculptGestureTrimOperation {
 
   eSculptTrimOperationType mode;
   eSculptTrimOrientationType orientation;
+  eSculptTrimLocationType location;
 } SculptGestureTrimOperation;
 
 static void sculpt_gesture_trim_normals_update(SculptGestureContext *sgcontext)
@@ -1053,8 +1072,19 @@ static void sculpt_gesture_trim_calculate_depth(bContext *C, SculptGestureContex
 
   if (trim_operation->use_cursor_depth) {
     float world_space_gesture_initial_location[3];
-    mul_v3_m4v3(
-        world_space_gesture_initial_location, vc->obact->obmat, ss->gesture_initial_location);
+
+    switch (trim_operation->location) {
+      case SCULPT_GESTURE_TRIM_LOCATION_DEPTH_SURFACE: {
+        mul_v3_m4v3(
+            world_space_gesture_initial_location, vc->obact->obmat, ss->gesture_initial_location);
+
+      } break;
+      case SCULPT_GESTURE_TRIM_LOCATION_DEPTH_VOLUME: {
+        float center_co[3];
+        mid_v3_v3v3(center_co, ss->gesture_initial_location, ss->gesture_initial_back_location);
+        mul_v3_m4v3(world_space_gesture_initial_location, vc->obact->obmat, center_co);
+      } break;
+    }
 
     float mid_point_depth;
     if (trim_operation->orientation == SCULPT_GESTURE_TRIM_ORIENTATION_VIEW) {
@@ -1362,6 +1392,7 @@ static void sculpt_gesture_init_trim_properties(SculptGestureContext *sgcontext,
   trim_operation->mode = RNA_enum_get(op->ptr, "trim_mode");
   trim_operation->use_cursor_depth = RNA_boolean_get(op->ptr, "use_cursor_depth");
   trim_operation->orientation = RNA_enum_get(op->ptr, "trim_orientation");
+  trim_operation->location = RNA_enum_get(op->ptr, "trim_location");
 
   /* If the cursor was not over the mesh, force the orientation to view. */
   if (!sgcontext->ss->gesture_initial_hit) {
@@ -1389,6 +1420,13 @@ static void sculpt_trim_gesture_operator_properties(wmOperatorType *ot)
                SCULPT_GESTURE_TRIM_ORIENTATION_VIEW,
                "Shape Orientation",
                NULL);
+
+  RNA_def_enum(ot->srna,
+               "trim_location",
+               prop_trim_location_types,
+               SCULPT_GESTURE_TRIM_LOCATION_DEPTH_SURFACE,
+               "Shape Location",
+               NULL);
 }
 
 /* Project Gesture Operation. */
@@ -1582,7 +1620,7 @@ static int sculpt_trim_gesture_box_invoke(bContext *C, wmOperator *op, const wmE
   SculptCursorGeometryInfo sgi;
   float mouse[2] = {event->mval[0], event->mval[1]};
   SCULPT_vertex_random_access_ensure(ss);
-  ss->gesture_initial_hit = SCULPT_cursor_geometry_info_update(C, &sgi, mouse, false);
+  ss->gesture_initial_hit = SCULPT_cursor_geometry_info_update(C, &sgi, mouse, false, false);
   if (ss->gesture_initial_hit) {
     copy_v3_v3(ss->gesture_initial_location, sgi.location);
     copy_v3_v3(ss->gesture_initial_normal, sgi.normal);
@@ -1623,9 +1661,10 @@ static int sculpt_trim_gesture_lasso_invoke(bContext *C, wmOperator *op, const w
   SculptCursorGeometryInfo sgi;
   float mouse[2] = {event->mval[0], event->mval[1]};
   SCULPT_vertex_random_access_ensure(ss);
-  ss->gesture_initial_hit = SCULPT_cursor_geometry_info_update(C, &sgi, mouse, false);
+  ss->gesture_initial_hit = SCULPT_cursor_geometry_info_update(C, &sgi, mouse, false, true);
   if (ss->gesture_initial_hit) {
     copy_v3_v3(ss->gesture_initial_location, sgi.location);
+    copy_v3_v3(ss->gesture_initial_back_location, sgi.back_location);
     copy_v3_v3(ss->gesture_initial_normal, sgi.normal);
   }