[Bf-blender-cvs] [148b39caec6] temp_bmesh_multires: Added some code to calculate principle curvature direction for uniform triangle tesselations (dyntopo). This will be used for a version of topological rake that aligns edge flows to lines of curvature automatically.

[Joseph Eagar]

Commit: 148b39caec6e5182179b2b6eee64f9c2c2fb92d9
Author: Joseph Eagar
Date:   Mon Mar 1 01:09:27 2021 -0800
Branches: temp_bmesh_multires
https://developer.blender.org/rB148b39caec6e5182179b2b6eee64f9c2c2fb92d9

Added some code to calculate principle curvature direction for
uniform triangle tesselations (dyntopo).  This will be used for
a version of topological rake that aligns edge flows to lines of curvature
automatically.

===================================================================

M	source/blender/blenkernel/intern/pbvh_bmesh.c
M	source/blender/editors/sculpt_paint/CMakeLists.txt
M	source/blender/editors/sculpt_paint/sculpt.c
M	source/blender/editors/sculpt_paint/sculpt_intern.h

===================================================================

diff --git a/source/blender/blenkernel/intern/pbvh_bmesh.c b/source/blender/blenkernel/intern/pbvh_bmesh.c
index 746463dfc42..2be64d19fd1 100644
--- a/source/blender/blenkernel/intern/pbvh_bmesh.c
+++ b/source/blender/blenkernel/intern/pbvh_bmesh.c
@@ -893,9 +893,9 @@ BLI_INLINE float calc_weighted_edge_collapse(EdgeQueueContext *eq_ctx, BMVert *v
   return l * (n*n*4.0f);
 #elif 1  // penalize 4-valence verts
   float l = len_squared_v3v3(v1->co, v2->co);
-  if (BM_vert_edge_count(v1) == 4 || BM_vert_edge_count(v2) == 4) {
-    l *= 0.25f;
-  }
+  //if (BM_vert_edge_count(v1) == 4 || BM_vert_edge_count(v2) == 4) {
+  //  l *= 0.25f;
+  //}
 
   return l;
 #else
@@ -3042,6 +3042,7 @@ bool BKE_pbvh_bmesh_update_topology(PBVH *pbvh,
                                     int sym_axis,
                                     bool updatePBVH)
 {
+  /*
   if (sym_axis >= 0 &&
       PIL_check_seconds_timer() - last_update_time[sym_axis] < DYNTOPO_RUN_INTERVAL) {
     return false;
@@ -3049,7 +3050,7 @@ bool BKE_pbvh_bmesh_update_topology(PBVH *pbvh,
 
   if (sym_axis >= 0) {
     last_update_time[sym_axis] = PIL_check_seconds_timer();
-  }
+  }*/
 
   /* 2 is enough for edge faces - manifold edge */
   BLI_buffer_declare_static(BMLoop *, edge_loops, BLI_BUFFER_NOP, 2);
diff --git a/source/blender/editors/sculpt_paint/CMakeLists.txt b/source/blender/editors/sculpt_paint/CMakeLists.txt
index fff8d27ef5b..5b426e827e7 100644
--- a/source/blender/editors/sculpt_paint/CMakeLists.txt
+++ b/source/blender/editors/sculpt_paint/CMakeLists.txt
@@ -56,6 +56,7 @@ set(SRC
   paint_vertex_weight_ops.c
   paint_vertex_weight_utils.c
   sculpt.c
+  sculpt_curvature.c
   sculpt_automasking.c
   sculpt_boundary.c
   sculpt_cloth.c
diff --git a/source/blender/editors/sculpt_paint/sculpt.c b/source/blender/editors/sculpt_paint/sculpt.c
index 2d9df99210f..b593b51c1e5 100644
--- a/source/blender/editors/sculpt_paint/sculpt.c
+++ b/source/blender/editors/sculpt_paint/sculpt.c
@@ -3237,7 +3237,8 @@ typedef struct {
   bool original;
 } SculptFindNearestToRayData;
 
-static void do_topology_rake_bmesh_task_cb_ex(void *__restrict userdata,
+__attribute__((optnone))  static void do_topology_rake_bmesh_task_cb_ex(
+    void *__restrict userdata,
                                               const int n,
                                               const TaskParallelTLS *__restrict tls)
 {
@@ -3273,6 +3274,8 @@ static void do_topology_rake_bmesh_task_cb_ex(void *__restrict userdata,
     if (!sculpt_brush_test_sq_fn(&test, vd.co)) {
       continue;
     }
+
+    float direction2[3];
     const float fade =
         bstrength *
         SCULPT_brush_strength_factor(
@@ -3281,7 +3284,12 @@ static void do_topology_rake_bmesh_task_cb_ex(void *__restrict userdata,
 
     float avg[3], val[3];
 
-    SCULPT_bmesh_four_neighbor_average(avg, direction, vd.bm_vert);
+    //SculptCurvatureData cdata;
+    //SCULPT_calc_principle_curvatures(ss, vd.vertex, &cdata);
+    //copy_v3_v3(direction2, cdata.principle[0]);
+    copy_v3_v3(direction2, direction);
+
+    SCULPT_bmesh_four_neighbor_average(avg, direction2, vd.bm_vert);
 
     sub_v3_v3v3(val, avg, vd.co);
 
diff --git a/source/blender/editors/sculpt_paint/sculpt_intern.h b/source/blender/editors/sculpt_paint/sculpt_intern.h
index 2c493876751..10433b90e16 100644
--- a/source/blender/editors/sculpt_paint/sculpt_intern.h
+++ b/source/blender/editors/sculpt_paint/sculpt_intern.h
@@ -1233,3 +1233,14 @@ bool SCULPT_ensure_dyntopo_node_undo(struct Object *ob,
 
 void SCULPT_update_flat_vcol_shading(struct Object *ob, struct Scene *scene);
 float SCULPT_calc_concavity(SculptSession *ss, SculptVertRef vref);
+
+
+typedef struct SculptCurvatureData {
+  float ks[3];
+  float principle[3][3];  // normalized
+} SculptCurvatureData;
+
+bool SCULPT_calc_principle_curvatures(SculptSession *ss,
+                                      SculptVertRef vertex,
+                                      SculptCurvatureData *out);
+