1 files changed, 55 insertions, 24 deletions

diff --git a/source/blender/blenkernel/intern/brush.c b/source/blender/blenkernel/intern/brush.c
index a816e4354b8..1b77989c2b8 100644
--- a/source/blender/blenkernel/intern/brush.c
+++ b/source/blender/blenkernel/intern/brush.c
@@ -50,7 +50,7 @@
 #include "IMB_imbuf.h"
 #include "IMB_imbuf_types.h"
 
-#include "RE_render_ext.h" /* RE_texture_evaluate */
+#include "RE_texture.h" /* RE_texture_evaluate */
 
 #include "BLO_read_write.h"
 
@@ -170,7 +170,7 @@ static void brush_make_local(Main *bmain, ID *id, const int flags)
       id_fake_user_set(&brush->id);
     }
     else {
-      Brush *brush_new = BKE_brush_copy(bmain, brush); /* Ensures FAKE_USER is set */
+      Brush *brush_new = (Brush *)BKE_id_copy(bmain, &brush->id); /* Ensures FAKE_USER is set */
 
       brush_new->id.us = 0;
 
@@ -250,7 +250,7 @@ static void brush_blend_read_data(BlendDataReader *reader, ID *id)
 {
   Brush *brush = (Brush *)id;
 
-  /* fallof curve */
+  /* Falloff curve. */
   BLO_read_data_address(reader, &brush->curve);
 
   BLO_read_data_address(reader, &brush->gradient);
@@ -355,6 +355,37 @@ static void brush_blend_read_expand(BlendExpander *expander, ID *id)
   }
 }
 
+static int brush_undo_preserve_cb(LibraryIDLinkCallbackData *cb_data)
+{
+  BlendLibReader *reader = cb_data->user_data;
+  ID *id_old = *cb_data->id_pointer;
+  /* Old data has not been remapped to new values of the pointers, if we want to keep the old
+   * pointer here we need its new address. */
+  ID *id_old_new = id_old != NULL ? BLO_read_get_new_id_address(reader, id_old->lib, id_old) :
+                                    NULL;
+  BLI_assert(id_old_new == NULL || ELEM(id_old, id_old_new, id_old_new->orig_id));
+  if (cb_data->cb_flag & IDWALK_CB_USER) {
+    id_us_plus_no_lib(id_old_new);
+    id_us_min(id_old);
+  }
+  *cb_data->id_pointer = id_old_new;
+  return IDWALK_RET_NOP;
+}
+
+static void brush_undo_preserve(BlendLibReader *reader, ID *id_new, ID *id_old)
+{
+  /* Whole Brush is preserved accross undo's. */
+  BKE_lib_id_swap(NULL, id_new, id_old);
+
+  /* `id_new` now has content from `id_old`, we need to ensure those old ID pointers are valid.
+   * Note: Since we want to re-use all old pointers here, code is much simpler than for Scene. */
+  BKE_library_foreach_ID_link(NULL, id_new, brush_undo_preserve_cb, reader, IDWALK_NOP);
+
+  /* Note: We do not swap IDProperties, as dealing with potential ID pointers in those would be
+   *       fairly delicate. */
+  SWAP(IDProperty *, id_new->properties, id_old->properties);
+}
+
 IDTypeInfo IDType_ID_BR = {
     .id_code = ID_BR,
     .id_filter = FILTER_ID_BR,
@@ -363,7 +394,7 @@ IDTypeInfo IDType_ID_BR = {
     .name = "Brush",
     .name_plural = "brushes",
     .translation_context = BLT_I18NCONTEXT_ID_BRUSH,
-    .flags = 0,
+    .flags = IDTYPE_FLAGS_NO_ANIMDATA,
 
     .init_data = brush_init_data,
     .copy_data = brush_copy_data,
@@ -376,6 +407,8 @@ IDTypeInfo IDType_ID_BR = {
     .blend_read_data = brush_blend_read_data,
     .blend_read_lib = brush_blend_read_lib,
     .blend_read_expand = brush_blend_read_expand,
+
+    .blend_read_undo_preserve = brush_undo_preserve,
 };
 
 static RNG *brush_rng;
@@ -455,9 +488,7 @@ Brush *BKE_brush_add(Main *bmain, const char *name, const eObjectMode ob_mode)
 {
   Brush *brush;
 
-  brush = BKE_libblock_alloc(bmain, ID_BR, name, 0);
-
-  brush_init_data(&brush->id);
+  brush = BKE_id_new(bmain, ID_BR, name);
 
   brush->ob_mode = ob_mode;
 
@@ -1531,13 +1562,6 @@ struct Brush *BKE_brush_first_search(struct Main *bmain, const eObjectMode ob_mo
   return NULL;
 }
 
-Brush *BKE_brush_copy(Main *bmain, const Brush *brush)
-{
-  Brush *brush_copy;
-  BKE_id_copy(bmain, &brush->id, (ID **)&brush_copy);
-  return brush_copy;
-}
-
 void BKE_brush_debug_print_state(Brush *br)
 {
   /* create a fake brush and set it to the defaults */
@@ -1545,20 +1569,28 @@ void BKE_brush_debug_print_state(Brush *br)
   brush_defaults(&def);
 
 #define BR_TEST(field, t) \
-  if (br->field != def.field) \
-  printf("br->" #field " = %" #t ";\n", br->field)
+  if (br->field != def.field) { \
+    printf("br->" #field " = %" #t ";\n", br->field); \
+  } \
+  ((void)0)
 
 #define BR_TEST_FLAG(_f) \
-  if ((br->flag & _f) && !(def.flag & _f)) \
+  if ((br->flag & _f) && !(def.flag & _f)) { \
     printf("br->flag |= " #_f ";\n"); \
-  else if (!(br->flag & _f) && (def.flag & _f)) \
-  printf("br->flag &= ~" #_f ";\n")
+  } \
+  else if (!(br->flag & _f) && (def.flag & _f)) { \
+    printf("br->flag &= ~" #_f ";\n"); \
+  } \
+  ((void)0)
 
 #define BR_TEST_FLAG_OVERLAY(_f) \
-  if ((br->overlay_flags & _f) && !(def.overlay_flags & _f)) \
+  if ((br->overlay_flags & _f) && !(def.overlay_flags & _f)) { \
     printf("br->overlay_flags |= " #_f ";\n"); \
-  else if (!(br->overlay_flags & _f) && (def.overlay_flags & _f)) \
-  printf("br->overlay_flags &= ~" #_f ";\n")
+  } \
+  else if (!(br->overlay_flags & _f) && (def.overlay_flags & _f)) { \
+    printf("br->overlay_flags &= ~" #_f ";\n"); \
+  } \
+  ((void)0)
 
   /* print out any non-default brush state */
   BR_TEST(normal_weight, f);
@@ -1708,11 +1740,10 @@ void BKE_brush_sculpt_reset(Brush *br)
     case SCULPT_TOOL_SCRAPE:
     case SCULPT_TOOL_FILL:
       br->alpha = 0.7f;
-      br->area_radius_factor = 1.0f;
+      br->area_radius_factor = 0.5f;
       br->spacing = 7;
       br->flag |= BRUSH_ACCUMULATE;
       br->flag |= BRUSH_INVERT_TO_SCRAPE_FILL;
-      br->flag2 |= BRUSH_AREA_RADIUS_PRESSURE;
       break;
     case SCULPT_TOOL_ROTATE:
       br->alpha = 1.0;