Sculpt dyntopo: Added a 'hard edge mode' option

to forcibly set autosmooth_fset_slide to zero
(i.e. treat face set boundaries as hard edges
and not project them on the surface).

release/scripts/startup/bl_ui/properties_paint_common.py

@@ -549,7 +549,17 @@ def brush_settings(layout, context, brush, popover=False):
         if context.preferences.experimental.use_sculpt_tools_tilt and capabilities.has_tilt:
             layout.prop(brush, "tilt_strength_factor", slider=True)
 
+        UnifiedPaintPanel.prop_unified(
+                layout,
+                context,
+                brush,
+                "hard_edge_mode",
+                slider=True,
+                unified_name="use_unified_hard_edge_mode",
+         )
+
         row = layout.row(align=True)
+
         row.prop(brush, "hardness", slider=True)
         row.prop(brush, "invert_hardness_pressure", text="")
         row.prop(brush, "use_hardness_pressure", text="")

source/blender/blenkernel/BKE_blender_version.h

@@ -39,7 +39,7 @@ extern "C" {
 
 /* Blender file format version. */
 #define BLENDER_FILE_VERSION BLENDER_VERSION
-#define BLENDER_FILE_SUBVERSION 21
+#define BLENDER_FILE_SUBVERSION 22
 
 /* Minimum Blender version that supports reading file written with the current
  * version. Older Blender versions will test this and show a warning if the file

source/blender/blenkernel/BKE_brush.h

@@ -155,6 +155,11 @@ void BKE_brush_debug_print_state(struct Brush *br);
 
 void BKE_brush_get_dyntopo(struct Brush *brush, struct Sculpt *sd, struct DynTopoSettings *out);
 
+bool BKE_brush_hard_edge_mode_get(const struct Scene *scene, const struct Brush *brush);
+void BKE_brush_hard_edge_mode_set(struct Scene *scene, struct Brush *brush, bool val);
+
+float BKE_brush_fset_slide_get(const struct Scene *scene, const struct Brush *brush);
+
 #ifdef __cplusplus
 }
 #endif

source/blender/blenkernel/intern/brush.c

@@ -2755,3 +2755,36 @@ void BKE_brush_get_dyntopo(Brush *brush, Sculpt *sd, DynTopoSettings *out)
     }
   }
 };
+
+bool BKE_brush_hard_edge_mode_get(const Scene *scene, const Brush *brush)
+{
+  UnifiedPaintSettings *ups = &scene->toolsettings->unified_paint_settings;
+  bool ret = (ups->flag & UNIFIED_PAINT_FLAG_HARD_EDGE_MODE) ? ups->hard_edge_mode :
+                                                               brush->flag2 & BRUSH_HARD_EDGE_MODE;
+
+  return ret;
+}
+
+void BKE_brush_hard_edge_mode_set(Scene *scene, Brush *brush, bool val)
+{
+  UnifiedPaintSettings *ups = &scene->toolsettings->unified_paint_settings;
+
+  if (ups->flag & UNIFIED_PAINT_FLAG_HARD_EDGE_MODE) {
+    ups->hard_edge_mode = val;
+  }
+  else {
+    if (val) {
+      brush->flag2 |= BRUSH_HARD_EDGE_MODE;
+    }
+    else {
+      brush->flag2 &= ~BRUSH_HARD_EDGE_MODE;
+    }
+  }
+}
+
+float BKE_brush_fset_slide_get(const Scene *scene, const Brush *brush)
+{
+  UnifiedPaintSettings *ups = &scene->toolsettings->unified_paint_settings;
+
+  return BKE_brush_hard_edge_mode_get(scene, brush) ? 0.0f : brush->autosmooth_fset_slide;
+}

source/blender/blenloader/intern/versioning_280.c

@@ -4424,7 +4424,7 @@ void blo_do_versions_280(FileData *fd, Library *UNUSED(lib), Main *bmain)
     for (Scene *scene = bmain->scenes.first; scene; scene = scene->id.next) {
       ToolSettings *ts = scene->toolsettings;
       UnifiedPaintSettings *ups = &ts->unified_paint_settings;
-      ups->flag &= ~(UNIFIED_PAINT_FLAG_UNUSED_0 | UNIFIED_PAINT_FLAG_UNUSED_1);
+      ups->flag &= ~(UNIFIED_PAINT_FLAG_UNUSED_1);
     }
 
     /* Set the default render pass in the viewport to Combined. */

source/blender/blenloader/intern/versioning_300.c

@@ -1169,6 +1169,15 @@ void blo_do_versions_300(FileData *fd, Library *UNUSED(lib), Main *bmain)
     }
   }
 
+  if (!MAIN_VERSION_ATLEAST(bmain, 300, 22)) {
+    LISTBASE_FOREACH (Scene *, scene, &bmain->scenes) {
+      ToolSettings *ts = scene->toolsettings;
+
+      if (ts) {
+        ts->unified_paint_settings.flag |= UNIFIED_PAINT_FLAG_HARD_EDGE_MODE;
+      }
+    }
+  }
   /**
    * Versioning code until next subversion bump goes here.
    *

source/blender/editors/sculpt_paint/sculpt_smooth.c

@@ -87,7 +87,7 @@ void SCULPT_neighbor_coords_average_interior(SculptSession *ss,
 
   int bflag = SCULPT_BOUNDARY_MESH | SCULPT_BOUNDARY_SHARP;
   float bound_smooth = powf(ss->cache->brush->boundary_smooth_factor, BOUNDARY_SMOOTH_EXP);
-  float slide_fset = ss->cache->brush->autosmooth_fset_slide;
+  float slide_fset = BKE_brush_fset_slide_get(ss->scene, ss->cache->brush);
 
   slide_fset = MAX2(slide_fset, bound_smooth);
 
@@ -1046,7 +1046,7 @@ static void do_smooth_brush_task_cb_ex(void *__restrict userdata,
 
   bool modified = false;
   const float bound_smooth = powf(ss->cache->brush->boundary_smooth_factor, BOUNDARY_SMOOTH_EXP);
-  const float slide_fset = ss->cache->brush->autosmooth_fset_slide;
+  const float slide_fset = BKE_brush_fset_slide_get(ss->scene, ss->cache->brush);
 
   SculptCustomLayer *bound_scl = data->scl2;
 

source/blender/makesdna/DNA_brush_enums.h

@@ -420,6 +420,9 @@ typedef enum eBrushFlags2 {
 
   /*topology rake in dynamic mode*/
   BRUSH_DYNAMIC_RAKE = (1 << 15),
+
+  /* sets face set slide to 0.0 */
+  BRUSH_HARD_EDGE_MODE = (1 << 16),
 } eBrushFlags2;
 
 typedef enum {

source/blender/makesdna/DNA_scene_defaults.h

@@ -290,7 +290,7 @@
     .unprojected_radius = 0.29, \
     .alpha = 0.5f, \
     .weight = 0.5f, \
-    .flag = UNIFIED_PAINT_SIZE | UNIFIED_PAINT_ALPHA, \
+    .flag = UNIFIED_PAINT_SIZE | UNIFIED_PAINT_ALPHA | UNIFIED_PAINT_FLAG_HARD_EDGE_MODE, \
   }
 
 #define _DNA_DEFAULTS_ParticleEditSettings \

source/blender/makesdna/DNA_scene_types.h

@@ -1244,7 +1244,8 @@ typedef struct UnifiedPaintSettings {
   float pixel_radius;
   float initial_pixel_radius;
 
-  char _pad[4];
+  char _pad[3];
+  char hard_edge_mode;
 
   /* drawing pressure */
   float size_pressure_value;
@@ -1268,7 +1269,7 @@ typedef enum {
 
   /* only used if unified size is enabled, mirrors the brush flag BRUSH_LOCK_SIZE */
   UNIFIED_PAINT_BRUSH_LOCK_SIZE = (1 << 2),
-  UNIFIED_PAINT_FLAG_UNUSED_0 = (1 << 3),
+  UNIFIED_PAINT_FLAG_HARD_EDGE_MODE = (1 << 3),
 
   UNIFIED_PAINT_FLAG_UNUSED_1 = (1 << 4),
 } eUnifiedPaintSettingsFlags;

source/blender/makesrna/intern/rna_brush.c

@@ -3349,6 +3349,12 @@ static void rna_def_brush(BlenderRNA *brna)
       prop, "Preserve Face Sets", "Preserve face set boundaries when smoothing");
   RNA_def_property_update(prop, 0, "rna_Brush_update");
 
+  prop = RNA_def_property(srna, "hard_edge_mode", PROP_BOOLEAN, PROP_NONE);
+  RNA_def_property_boolean_sdna(prop, NULL, "flag2", BRUSH_HARD_EDGE_MODE);
+  RNA_def_property_ui_text(
+      prop, "Hard Edge Mode", "Hard edge mode; treat all face set boundaries as hard edges");
+  RNA_def_property_update(prop, 0, "rna_Brush_update");
+
   prop = RNA_def_property(srna, "use_grab_silhouette", PROP_BOOLEAN, PROP_NONE);
   RNA_def_property_boolean_sdna(prop, NULL, "flag2", BRUSH_GRAB_SILHOUETTE);
   RNA_def_property_ui_text(

source/blender/makesrna/intern/rna_scene.c

@@ -3597,6 +3597,12 @@ static void rna_def_unified_paint_settings(BlenderRNA *brna)
                            "Use Unified Radius",
                            "Instead of per-brush radius, the radius is shared across brushes");
 
+  /* high-level flags to enable or disable unified paint settings */
+  prop = RNA_def_property(srna, "use_unified_hard_edge_mode", PROP_BOOLEAN, PROP_NONE);
+  RNA_def_property_boolean_sdna(prop, NULL, "flag", UNIFIED_PAINT_FLAG_HARD_EDGE_MODE);
+  RNA_def_property_ui_text(
+      prop, "Use Unified Hard Edge Mode", "Use global setting for hard edge mode");
+
   prop = RNA_def_property(srna, "use_unified_strength", PROP_BOOLEAN, PROP_NONE);
   RNA_def_property_boolean_sdna(prop, NULL, "flag", UNIFIED_PAINT_ALPHA);
   RNA_def_property_ui_text(prop,
@@ -3669,6 +3675,13 @@ static void rna_def_unified_paint_settings(BlenderRNA *brna)
   RNA_def_property_enum_items(prop, brush_size_unit_items);
   RNA_def_property_ui_text(
       prop, "Radius Unit", "Measure brush size relative to the view or the scene");
+
+  prop = RNA_def_property(srna, "hard_edge_mode", PROP_BOOLEAN, PROP_NONE);
+  RNA_def_property_boolean_sdna(prop, NULL, "hard_edge_mode", 1);
+  RNA_def_property_flag(prop, PROP_CONTEXT_UPDATE);
+  RNA_def_property_ui_text(
+      prop, "Hard Edge Mode", "Hard edge mode; treat all face set boundaries as hard edges");
+  RNA_def_property_update(prop, 0, "rna_UnifiedPaintSettings_update");
 }
 
 static void rna_def_curve_paint_settings(BlenderRNA *brna)