[Bf-blender-cvs] [ec4b9dff19c] temp_bmesh_multires: Add 'projection' option for volume-preserving smoothing to smooth corrective modifier

[Joseph Eagar]

Commit: ec4b9dff19c3105a9c7069d6544fca6e0323f1f7
Author: Joseph Eagar
Date:   Fri Jul 23 15:46:01 2021 -0700
Branches: temp_bmesh_multires
https://developer.blender.org/rBec4b9dff19c3105a9c7069d6544fca6e0323f1f7

Add 'projection' option for volume-preserving smoothing to
smooth corrective modifier

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

M	source/blender/makesdna/DNA_modifier_types.h
M	source/blender/makesrna/intern/rna_modifier.c
M	source/blender/modifiers/intern/MOD_correctivesmooth.c

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

diff --git a/source/blender/makesdna/DNA_modifier_types.h b/source/blender/makesdna/DNA_modifier_types.h
index 0dc5ec86187..781e3acbe4a 100644
--- a/source/blender/makesdna/DNA_modifier_types.h
+++ b/source/blender/makesdna/DNA_modifier_types.h
@@ -1843,10 +1843,10 @@ typedef struct CorrectiveSmoothModifierData {
   /* NOTE: -1 is used to bind. */
   unsigned int bind_coords_num;
 
-  float lambda, scale;
+  float lambda, scale, projection;
   short repeat, flag;
   char smooth_type, rest_source;
-  char _pad[6];
+  char _pad[2];
 
   /** MAX_VGROUP_NAME. */
   char defgrp_name[64];
@@ -1900,10 +1900,7 @@ typedef struct UVWarpModifierData {
 } UVWarpModifierData;
 
 /* UVWarp modifier flags */
-enum {
-  MOD_UVWARP_INVERT_VGROUP = 1 << 0,
-  MOD_UVWARP_RESTRICT_ISLANDS = 1<<1
-};
+enum { MOD_UVWARP_INVERT_VGROUP = 1 << 0, MOD_UVWARP_RESTRICT_ISLANDS = 1 << 1 };
 
 /* cache modifier */
 typedef struct MeshCacheModifierData {
diff --git a/source/blender/makesrna/intern/rna_modifier.c b/source/blender/makesrna/intern/rna_modifier.c
index a35755473f9..1e7e940448e 100644
--- a/source/blender/makesrna/intern/rna_modifier.c
+++ b/source/blender/makesrna/intern/rna_modifier.c
@@ -3296,6 +3296,13 @@ static void rna_def_modifier_correctivesmooth(BlenderRNA *brna)
   RNA_def_property_ui_text(prop, "Lambda Factor", "Smooth factor effect");
   RNA_def_property_update(prop, 0, "rna_CorrectiveSmoothModifier_update");
 
+  prop = RNA_def_property(srna, "projection", PROP_FLOAT, PROP_FACTOR);
+  RNA_def_property_float_sdna(prop, NULL, "projection");
+  RNA_def_property_range(prop, -FLT_MAX, FLT_MAX);
+  RNA_def_property_ui_range(prop, 0.0, 1.0, 5, 3);
+  RNA_def_property_ui_text(prop, "Projection", "Volume preserving projection");
+  RNA_def_property_update(prop, 0, "rna_CorrectiveSmoothModifier_update");
+
   prop = RNA_def_property(srna, "iterations", PROP_INT, PROP_NONE);
   RNA_def_property_int_sdna(prop, NULL, "repeat");
   RNA_def_property_ui_range(prop, 0, 200, 1, -1);
diff --git a/source/blender/modifiers/intern/MOD_correctivesmooth.c b/source/blender/modifiers/intern/MOD_correctivesmooth.c
index 9e8f5bee396..ede301889a0 100644
--- a/source/blender/modifiers/intern/MOD_correctivesmooth.c
+++ b/source/blender/modifiers/intern/MOD_correctivesmooth.c
@@ -193,7 +193,10 @@ static void smooth_iter__simple(CorrectiveSmoothModifierData *csmd,
   uint i;
 
   const uint numEdges = (uint)mesh->totedge;
+  const float projection = csmd->projection;
+
   const MEdge *edges = mesh->medge;
+  const MVert *verts = mesh->mvert;
   float *vertex_edge_count_div;
 
   struct SmoothingData_Simple {
@@ -239,8 +242,24 @@ static void smooth_iter__simple(CorrectiveSmoothModifierData *csmd,
       sd_v1 = &smooth_data[edges[i].v1];
       sd_v2 = &smooth_data[edges[i].v2];
 
-      add_v3_v3(sd_v1->delta, edge_dir);
-      sub_v3_v3(sd_v2->delta, edge_dir);
+      if (projection > 0.0f) {
+        float edge_dir2[3];
+        float no[3];
+
+        normal_short_to_float_v3(no, verts[edges[i].v1].no);
+        madd_v3_v3v3fl(edge_dir2, edge_dir, no, -dot_v3v3(edge_dir, no) * projection);
+        add_v3_v3(sd_v1->delta, edge_dir2);
+
+        negate_v3(edge_dir);
+
+        normal_short_to_float_v3(no, verts[edges[i].v2].no);
+        madd_v3_v3v3fl(edge_dir2, edge_dir, no, -dot_v3v3(edge_dir, no) * projection);
+        add_v3_v3(sd_v2->delta, edge_dir2);
+      }
+      else {
+        add_v3_v3(sd_v1->delta, edge_dir);
+        sub_v3_v3(sd_v2->delta, edge_dir);
+      }
     }
 
     for (i = 0; i < numVerts; i++) {
@@ -270,7 +289,9 @@ static void smooth_iter__length_weight(CorrectiveSmoothModifierData *csmd,
   /* NOTE: the way this smoothing method works, its approx half as strong as the simple-smooth,
    * and 2.0 rarely spikes, double the value for consistent behavior. */
   const float lambda = csmd->lambda * 2.0f;
+  const float projection = csmd->projection;
   const MEdge *edges = mesh->medge;
+  const MVert *verts = mesh->mvert;
   float *vertex_edge_count;
   uint i;
 
@@ -305,8 +326,24 @@ static void smooth_iter__length_weight(CorrectiveSmoothModifierData *csmd,
       sd_v1 = &smooth_data[edges[i].v1];
       sd_v2 = &smooth_data[edges[i].v2];
 
-      add_v3_v3(sd_v1->delta, edge_dir);
-      sub_v3_v3(sd_v2->delta, edge_dir);
+      if (projection > 0.0f) {
+        float edge_dir2[3];
+        float no[3];
+
+        normal_short_to_float_v3(no, verts[edges[i].v1].no);
+        madd_v3_v3v3fl(edge_dir2, edge_dir, no, -dot_v3v3(edge_dir, no) * projection);
+        add_v3_v3(sd_v1->delta, edge_dir2);
+
+        negate_v3(edge_dir);
+
+        normal_short_to_float_v3(no, verts[edges[i].v2].no);
+        madd_v3_v3v3fl(edge_dir2, edge_dir, no, -dot_v3v3(edge_dir, no) * projection);
+        add_v3_v3(sd_v2->delta, edge_dir2);
+      }
+      else {
+        add_v3_v3(sd_v1->delta, edge_dir);
+        sub_v3_v3(sd_v2->delta, edge_dir);
+      }
 
       sd_v1->edge_length_sum += edge_dist;
       sd_v2->edge_length_sum += edge_dist;
@@ -787,6 +824,7 @@ static void panel_draw(const bContext *UNUSED(C), Panel *panel)
   uiLayoutSetPropSep(layout, true);
 
   uiItemR(layout, ptr, "factor", 0, IFACE_("Factor"), ICON_NONE);
+  uiItemR(layout, ptr, "projection", 0, IFACE_("Projection"), ICON_NONE);
   uiItemR(layout, ptr, "iterations", 0, NULL, ICON_NONE);
   uiItemR(layout, ptr, "scale", 0, NULL, ICON_NONE);
   uiItemR(layout, ptr, "smooth_type", 0, NULL, ICON_NONE);
@@ -821,6 +859,13 @@ static void blendWrite(BlendWriter *writer, const ModifierData *md)
   }
 }
 
+bool dependsOnNormals(ModifierData *md)
+{
+  CorrectiveSmoothModifierData *csmd = (CorrectiveSmoothModifierData *)md;
+
+  return csmd->projection > 0.0f;
+}
+
 static void blendRead(BlendDataReader *reader, ModifierData *md)
 {
   CorrectiveSmoothModifierData *csmd = (CorrectiveSmoothModifierData *)md;
@@ -859,7 +904,7 @@ ModifierTypeInfo modifierType_CorrectiveSmooth = {
     /* isDisabled */ NULL,
     /* updateDepsgraph */ NULL,
     /* dependsOnTime */ NULL,
-    /* dependsOnNormals */ NULL,
+    /* dependsOnNormals */ dependsOnNormals,
     /* foreachIDLink */ NULL,
     /* foreachTexLink */ NULL,
     /* freeRuntimeData */ NULL,