Curves: Use only current brush location for delete brush

Currently the delete brush and some other brushes use the line
segment from the current brush position to the previous position
to find curves to interact with. However, this doesn't work well
with more advanced stroke settings that purposefully use
non-contiguous brush sample locations. This commit makes
the delete brush only use the current sample location.

Differential Revision: https://developer.blender.org/D14992

1 files changed, 12 insertions, 30 deletions

diff --git a/source/blender/editors/sculpt_paint/curves_sculpt_delete.cc b/source/blender/editors/sculpt_paint/curves_sculpt_delete.cc
index e610e4eeb61..8287dd49bd1 100644
--- a/source/blender/editors/sculpt_paint/curves_sculpt_delete.cc
+++ b/source/blender/editors/sculpt_paint/curves_sculpt_delete.cc
@@ -77,14 +77,12 @@ struct DeleteOperationExecutor {
   float brush_radius_re_;
 
   float2 brush_pos_re_;
-  float2 brush_pos_prev_re_;
 
   float4x4 curves_to_world_mat_;
   float4x4 world_to_curves_mat_;
 
   void execute(DeleteOperation &self, const bContext &C, const StrokeExtension &stroke_extension)
   {
-    BLI_SCOPED_DEFER([&]() { self.brush_pos_prev_re_ = stroke_extension.mouse_position; });
 
     self_ = &self;
     depsgraph_ = CTX_data_depsgraph_pointer(&C);
@@ -102,8 +100,6 @@ struct DeleteOperationExecutor {
     brush_radius_re_ = brush_radius_get(*scene_, *brush_, stroke_extension);
 
     brush_pos_re_ = stroke_extension.mouse_position;
-    brush_pos_prev_re_ = stroke_extension.is_first ? stroke_extension.mouse_position :
-                                                     self.brush_pos_prev_re_;
 
     curves_to_world_mat_ = object_->obmat;
     world_to_curves_mat_ = curves_to_world_mat_.inverted();
@@ -159,6 +155,8 @@ struct DeleteOperationExecutor {
 
     Span<float3> positions_cu = curves_->positions();
 
+    const float brush_radius_sq_re = pow2f(brush_radius_re_);
+
     threading::parallel_for(curves_->curves_range(), 512, [&](IndexRange curve_range) {
       for (const int curve_i : curve_range) {
         const IndexRange points = curves_->points_for_curve(curve_i);
@@ -170,8 +168,9 @@ struct DeleteOperationExecutor {
           ED_view3d_project_float_v2_m4(region_, pos1_cu, pos1_re, projection.values);
           ED_view3d_project_float_v2_m4(region_, pos2_cu, pos2_re, projection.values);
 
-          const float dist = dist_seg_seg_v2(pos1_re, pos2_re, brush_pos_prev_re_, brush_pos_re_);
-          if (dist <= brush_radius_re_) {
+          const float dist_sq_re = dist_squared_to_line_segment_v2(
+              brush_pos_re_, pos1_re, pos2_re);
+          if (dist_sq_re <= brush_radius_sq_re) {
             curves_to_delete[curve_i] = true;
             break;
           }
@@ -185,32 +184,23 @@ struct DeleteOperationExecutor {
     float4x4 projection;
     ED_view3d_ob_project_mat_get(rv3d_, object_, projection.values);
 
-    float3 brush_start_wo, brush_end_wo;
-    ED_view3d_win_to_3d(v3d_,
-                        region_,
-                        curves_to_world_mat_ * self_->brush_3d_.position_cu,
-                        brush_pos_prev_re_,
-                        brush_start_wo);
+    float3 brush_wo;
     ED_view3d_win_to_3d(v3d_,
                         region_,
                         curves_to_world_mat_ * self_->brush_3d_.position_cu,
                         brush_pos_re_,
-                        brush_end_wo);
-    const float3 brush_start_cu = world_to_curves_mat_ * brush_start_wo;
-    const float3 brush_end_cu = world_to_curves_mat_ * brush_end_wo;
+                        brush_wo);
+    const float3 brush_cu = world_to_curves_mat_ * brush_wo;
 
     const Vector<float4x4> symmetry_brush_transforms = get_symmetry_brush_transforms(
         eCurvesSymmetryType(curves_id_->symmetry));
 
     for (const float4x4 &brush_transform : symmetry_brush_transforms) {
-      this->delete_spherical(
-          brush_transform * brush_start_cu, brush_transform * brush_end_cu, curves_to_delete);
+      this->delete_spherical(brush_transform * brush_cu, curves_to_delete);
     }
   }
 
-  void delete_spherical(const float3 &brush_start_cu,
-                        const float3 &brush_end_cu,
-                        MutableSpan<bool> curves_to_delete)
+  void delete_spherical(const float3 &brush_cu, MutableSpan<bool> curves_to_delete)
   {
     Span<float3> positions_cu = curves_->positions();
 
@@ -224,16 +214,8 @@ struct DeleteOperationExecutor {
           const float3 &pos1_cu = positions_cu[segment_i];
           const float3 &pos2_cu = positions_cu[segment_i + 1];
 
-          float3 closest_segment_cu, closest_brush_cu;
-          isect_seg_seg_v3(pos1_cu,
-                           pos2_cu,
-                           brush_start_cu,
-                           brush_end_cu,
-                           closest_segment_cu,
-                           closest_brush_cu);
-          const float distance_to_brush_sq_cu = math::distance_squared(closest_segment_cu,
-                                                                       closest_brush_cu);
-          if (distance_to_brush_sq_cu > brush_radius_sq_cu) {
+          const float distance_sq_cu = dist_squared_to_line_segment_v3(brush_cu, pos1_cu, pos2_cu);
+          if (distance_sq_cu > brush_radius_sq_cu) {
             continue;
           }
           curves_to_delete[curve_i] = true;