Fix issue discovered while investigating T39950:

Sculpt mode drawing fails after deleting a subsurf modifier
in sculpt mode and undoing.

This was quite difficult to spot. Main cause was that mesh data was not
synchronized properly between undo and sculpt code because we generated
a pbvh on derivedmesh invalidation without really refreshing the rest of
the data. This could result in undo and drawing operating on different
data.

To solve this and avoid bad level calls I had to move quite some code
around. Crazyspace is now moved to blenkernel, as did some sculpt calls
that make sure sculpt data are properly refreshed.

13 files changed, 317 insertions, 259 deletions

diff --git a/source/blender/blenkernel/BKE_crazyspace.h b/source/blender/blenkernel/BKE_crazyspace.h
new file mode 100644
index 00000000000..89cbd9ec119
--- /dev/null
+++ b/source/blender/blenkernel/BKE_crazyspace.h
@@ -0,0 +1,54 @@
+/*
+ * ***** BEGIN GPL LICENSE BLOCK *****
+ *
+ * This program is free software; you can redistribute it and/or
+ * modify it under the terms of the GNU General Public License
+ * as published by the Free Software Foundation; either version 2
+ * of the License, or (at your option) any later version.
+ *
+ * This program is distributed in the hope that it will be useful,
+ * but WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+ * GNU General Public License for more details.
+ *
+ * You should have received a copy of the GNU General Public License
+ * along with this program; if not, write to the Free Software Foundation,
+ * Inc., 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301, USA.
+ *
+ * The Original Code is Copyright (C) 2008 Blender Foundation.
+ * All rights reserved.
+ *
+ *
+ * Contributor(s): Blender Foundation
+ *
+ * ***** END GPL LICENSE BLOCK *****
+ */
+
+/** \file BKE_crazyspace.h
+ *  \ingroup bke
+ */
+
+#ifndef __BKE_CRAZYSPACE_H__
+#define __BKE_CRAZYSPACE_H__
+
+#ifdef __cplusplus
+extern "C" {
+#endif
+struct Scene;
+struct Object;
+struct BMEditMesh;
+struct Mesh;
+
+/* crazyspace.c */
+float (*crazyspace_get_mapped_editverts(struct Scene *scene, struct Object *obedit))[3];
+void crazyspace_set_quats_editmesh(struct BMEditMesh *em, float (*origcos)[3], float (*mappedcos)[3], float (*quats)[4],
+								   const bool use_select);
+void crazyspace_set_quats_mesh(struct Mesh *me, float (*origcos)[3], float (*mappedcos)[3], float (*quats)[4]);
+int sculpt_get_first_deform_matrices(struct Scene *scene, struct Object *ob, float (**deformmats)[3][3], float (**deformcos)[3]);
+void crazyspace_build_sculpt(struct Scene *scene, struct Object *ob, float (**deformmats)[3][3], float (**deformcos)[3]);
+
+#ifdef __cplusplus
+}
+#endif
+
+#endif
diff --git a/source/blender/blenkernel/BKE_paint.h b/source/blender/blenkernel/BKE_paint.h
index df72cb988b1..cb521382bd3 100644
--- a/source/blender/blenkernel/BKE_paint.h
+++ b/source/blender/blenkernel/BKE_paint.h
@@ -47,6 +47,7 @@ struct Object;
 struct Paint;
 struct PBVH;
 struct Scene;
+struct Sculpt;
 struct StrokeCache;
 struct Tex;
 struct ImagePool;
@@ -176,4 +177,14 @@ void free_sculptsession(struct Object *ob);
 void free_sculptsession_deformMats(struct SculptSession *ss);
 void sculptsession_bm_to_me(struct Object *ob, bool reorder);
 void sculptsession_bm_to_me_for_render(struct Object *object);
+void sculpt_update_mesh_elements(struct Scene *scene, struct Sculpt *sd, struct Object *ob,
+								 bool need_pmap, bool need_mask);
+struct MultiresModifierData *sculpt_multires_active(struct Scene *scene, struct Object *ob);
+int ED_sculpt_mask_layers_ensure(struct Object *ob,
+								  struct MultiresModifierData *mmd);
+
+enum {
+	ED_SCULPT_MASK_LAYER_CALC_VERT = (1 << 0),
+	ED_SCULPT_MASK_LAYER_CALC_LOOP = (1 << 1)
+};
 #endif
diff --git a/source/blender/blenkernel/CMakeLists.txt b/source/blender/blenkernel/CMakeLists.txt
index 749a5eb408d..0caf7d11c55 100644
--- a/source/blender/blenkernel/CMakeLists.txt
+++ b/source/blender/blenkernel/CMakeLists.txt
@@ -78,7 +78,8 @@ set(SRC
 	intern/colortools.c
 	intern/constraint.c
 	intern/context.c
-	intern/curve.c
+        intern/crazyspace.c
+        intern/curve.c
 	intern/customdata.c
 	intern/customdata_file.c
 	intern/deform.c
@@ -191,6 +192,7 @@ set(SRC
 	BKE_colortools.h
 	BKE_constraint.h
 	BKE_context.h
+        BKE_crazyspace.h
 	BKE_curve.h
 	BKE_customdata.h
 	BKE_customdata_file.h
diff --git a/source/blender/blenkernel/intern/DerivedMesh.c b/source/blender/blenkernel/intern/DerivedMesh.c
index 26cc70e1089..228f4ce7730 100644
--- a/source/blender/blenkernel/intern/DerivedMesh.c
+++ b/source/blender/blenkernel/intern/DerivedMesh.c
@@ -2251,7 +2251,8 @@ static void mesh_build_data(Scene *scene, Object *ob, CustomDataMask dataMask,
 	if ((ob->mode & OB_MODE_SCULPT) && ob->sculpt) {
 		/* create PBVH immediately (would be created on the fly too,
 		 * but this avoids waiting on first stroke) */
-		ob->sculpt->pbvh = ob->derivedFinal->getPBVH(ob, ob->derivedFinal);
+
+		sculpt_update_mesh_elements(scene, scene->toolsettings->sculpt, ob, false, false);
 	}
 
 	BLI_assert(!(ob->derivedFinal->dirty & DM_DIRTY_NORMALS));
diff --git a/source/blender/editors/util/crazyspace.c b/source/blender/blenkernel/intern/crazyspace.c
index b90cfad28a5..610a0fe0fbc 100644
--- a/source/blender/editors/util/crazyspace.c
+++ b/source/blender/blenkernel/intern/crazyspace.c
@@ -25,8 +25,8 @@
  * ***** END GPL LICENSE BLOCK *****
  */
 
-/** \file blender/editors/util/crazyspace.c
- *  \ingroup edutil
+/** \file blender/blenkernel/intern/crazyspace.c
+ *  \ingroup bke
  */
 
 
@@ -42,14 +42,13 @@
 #include "BLI_math.h"
 #include "BLI_bitmap.h"
 
+#include "BKE_crazyspace.h"
 #include "BKE_DerivedMesh.h"
 #include "BKE_modifier.h"
 #include "BKE_multires.h"
 #include "BKE_mesh.h"
 #include "BKE_editmesh.h"
 
-#include "ED_util.h"
-
 typedef struct {
 	float (*vertexcos)[3];
 	BLI_bitmap *vertex_visit;
diff --git a/source/blender/blenkernel/intern/paint.c b/source/blender/blenkernel/intern/paint.c
index 1189b5715bb..d5059566dab 100644
--- a/source/blender/blenkernel/intern/paint.c
+++ b/source/blender/blenkernel/intern/paint.c
@@ -37,6 +37,7 @@
 #include "DNA_object_types.h"
 #include "DNA_mesh_types.h"
 #include "DNA_meshdata_types.h"
+#include "DNA_modifier_types.h"
 #include "DNA_scene_types.h"
 #include "DNA_brush_types.h"
 #include "DNA_space_types.h"
@@ -47,10 +48,14 @@
 
 #include "BKE_brush.h"
 #include "BKE_context.h"
+#include "BKE_crazyspace.h"
 #include "BKE_depsgraph.h"
 #include "BKE_global.h"
 #include "BKE_image.h"
+#include "BKE_key.h"
 #include "BKE_library.h"
+#include "BKE_mesh.h"
+#include "BKE_modifier.h"
 #include "BKE_object.h"
 #include "BKE_paint.h"
 #include "BKE_pbvh.h"
@@ -499,3 +504,239 @@ void free_sculptsession(Object *ob)
 		ob->sculpt = NULL;
 	}
 }
+
+/* Sculpt mode handles multires differently from regular meshes, but only if
+ * it's the last modifier on the stack and it is not on the first level */
+MultiresModifierData *sculpt_multires_active(Scene *scene, Object *ob)
+{
+	Mesh *me = (Mesh *)ob->data;
+	ModifierData *md;
+	VirtualModifierData virtualModifierData;
+
+	if (ob->sculpt && ob->sculpt->bm) {
+		/* can't combine multires and dynamic topology */
+		return NULL;
+	}
+
+	if (!CustomData_get_layer(&me->ldata, CD_MDISPS)) {
+		/* multires can't work without displacement layer */
+		return NULL;
+	}
+
+	for (md = modifiers_getVirtualModifierList(ob, &virtualModifierData); md; md = md->next) {
+		if (md->type == eModifierType_Multires) {
+			MultiresModifierData *mmd = (MultiresModifierData *)md;
+
+			if (!modifier_isEnabled(scene, md, eModifierMode_Realtime))
+				continue;
+
+			if (mmd->sculptlvl > 0) return mmd;
+			else return NULL;
+		}
+	}
+
+	return NULL;
+}
+
+
+/* Checks if there are any supported deformation modifiers active */
+static bool sculpt_modifiers_active(Scene *scene, Sculpt *sd, Object *ob)
+{
+	ModifierData *md;
+	Mesh *me = (Mesh *)ob->data;
+	MultiresModifierData *mmd = sculpt_multires_active(scene, ob);
+	VirtualModifierData virtualModifierData;
+
+	if (mmd || ob->sculpt->bm)
+		return 0;
+
+	/* non-locked shape keys could be handled in the same way as deformed mesh */
+	if ((ob->shapeflag & OB_SHAPE_LOCK) == 0 && me->key && ob->shapenr)
+		return 1;
+
+	md = modifiers_getVirtualModifierList(ob, &virtualModifierData);
+
+	/* exception for shape keys because we can edit those */
+	for (; md; md = md->next) {
+		ModifierTypeInfo *mti = modifierType_getInfo(md->type);
+		if (!modifier_isEnabled(scene, md, eModifierMode_Realtime)) continue;
+		if (md->type == eModifierType_ShapeKey) continue;
+
+		if (mti->type == eModifierTypeType_OnlyDeform) return 1;
+		else if ((sd->flags & SCULPT_ONLY_DEFORM) == 0) return 1;
+	}
+
+	return 0;
+}
+
+/**
+ * \param need_mask So the DerivedMesh thats returned has mask data
+ */
+void sculpt_update_mesh_elements(Scene *scene, Sculpt *sd, Object *ob,
+								 bool need_pmap, bool need_mask)
+{
+	DerivedMesh *dm;
+	SculptSession *ss = ob->sculpt;
+	Mesh *me = ob->data;
+	MultiresModifierData *mmd = sculpt_multires_active(scene, ob);
+
+	ss->modifiers_active = sculpt_modifiers_active(scene, sd, ob);
+	ss->show_diffuse_color = (sd->flags & SCULPT_SHOW_DIFFUSE) != 0;
+
+	if (need_mask) {
+		if (mmd == NULL) {
+			if (!CustomData_has_layer(&me->vdata, CD_PAINT_MASK)) {
+				ED_sculpt_mask_layers_ensure(ob, NULL);
+			}
+		}
+		else {
+			if (!CustomData_has_layer(&me->ldata, CD_GRID_PAINT_MASK)) {
+#if 1
+				ED_sculpt_mask_layers_ensure(ob, mmd);
+#else				/* if we wanted to support adding mask data while multi-res painting, we would need to do this */
+				if ((ED_sculpt_mask_layers_ensure(ob, mmd) & ED_SCULPT_MASK_LAYER_CALC_LOOP)) {
+					/* remake the derived mesh */
+					ob->recalc |= OB_RECALC_DATA;
+					BKE_object_handle_update(scene, ob);
+				}
+#endif
+			}
+		}
+	}
+
+	/* BMESH ONLY --- at some point we should move sculpt code to use polygons only - but for now it needs tessfaces */
+	BKE_mesh_tessface_ensure(me);
+
+	if (!mmd) ss->kb = BKE_keyblock_from_object(ob);
+	else ss->kb = NULL;
+
+	/* needs to be called after we ensure tessface */
+	dm = mesh_get_derived_final(scene, ob, CD_MASK_BAREMESH);
+
+	if (mmd) {
+		ss->multires = mmd;
+		ss->totvert = dm->getNumVerts(dm);
+		ss->totpoly = dm->getNumPolys(dm);
+		ss->mvert = NULL;
+		ss->mpoly = NULL;
+		ss->mloop = NULL;
+		ss->face_normals = NULL;
+	}
+	else {
+		ss->totvert = me->totvert;
+		ss->totpoly = me->totpoly;
+		ss->mvert = me->mvert;
+		ss->mpoly = me->mpoly;
+		ss->mloop = me->mloop;
+		ss->face_normals = NULL;
+		ss->multires = NULL;
+		ss->vmask = CustomData_get_layer(&me->vdata, CD_PAINT_MASK);
+	}
+
+	ss->pbvh = dm->getPBVH(ob, dm);
+	ss->pmap = (need_pmap && dm->getPolyMap) ? dm->getPolyMap(ob, dm) : NULL;
+
+	pbvh_show_diffuse_color_set(ss->pbvh, ss->show_diffuse_color);
+
+	if (ss->modifiers_active) {
+		if (!ss->orig_cos) {
+			int a;
+
+			free_sculptsession_deformMats(ss);
+
+			ss->orig_cos = (ss->kb) ? BKE_key_convert_to_vertcos(ob, ss->kb) : BKE_mesh_vertexCos_get(me, NULL);
+
+			crazyspace_build_sculpt(scene, ob, &ss->deform_imats, &ss->deform_cos);
+			BKE_pbvh_apply_vertCos(ss->pbvh, ss->deform_cos);
+
+			for (a = 0; a < me->totvert; ++a) {
+				invert_m3(ss->deform_imats[a]);
+			}
+		}
+	}
+	else {
+		free_sculptsession_deformMats(ss);
+	}
+
+	/* if pbvh is deformed, key block is already applied to it */
+	if (ss->kb && !BKE_pbvh_isDeformed(ss->pbvh)) {
+		float (*vertCos)[3] = BKE_key_convert_to_vertcos(ob, ss->kb);
+
+		if (vertCos) {
+			/* apply shape keys coordinates to PBVH */
+			BKE_pbvh_apply_vertCos(ss->pbvh, vertCos);
+			MEM_freeN(vertCos);
+		}
+	}
+}
+
+int ED_sculpt_mask_layers_ensure(Object *ob, MultiresModifierData *mmd)
+{
+	const float *paint_mask;
+	Mesh *me = ob->data;
+	int ret = 0;
+
+	paint_mask = CustomData_get_layer(&me->vdata, CD_PAINT_MASK);
+
+	/* if multires is active, create a grid paint mask layer if there
+	 * isn't one already */
+	if (mmd && !CustomData_has_layer(&me->ldata, CD_GRID_PAINT_MASK)) {
+		GridPaintMask *gmask;
+		int level = max_ii(1, mmd->sculptlvl);
+		int gridsize = BKE_ccg_gridsize(level);
+		int gridarea = gridsize * gridsize;
+		int i, j;
+
+		gmask = CustomData_add_layer(&me->ldata, CD_GRID_PAINT_MASK,
+									 CD_CALLOC, NULL, me->totloop);
+
+		for (i = 0; i < me->totloop; i++) {
+			GridPaintMask *gpm = &gmask[i];
+
+			gpm->level = level;
+			gpm->data = MEM_callocN(sizeof(float) * gridarea,
+									"GridPaintMask.data");
+		}
+
+		/* if vertices already have mask, copy into multires data */
+		if (paint_mask) {
+			for (i = 0; i < me->totpoly; i++) {
+				const MPoly *p = &me->mpoly[i];
+				float avg = 0;
+
+				/* mask center */
+				for (j = 0; j < p->totloop; j++) {
+					const MLoop *l = &me->mloop[p->loopstart + j];
+					avg += paint_mask[l->v];
+				}
+				avg /= (float)p->totloop;
+
+				/* fill in multires mask corner */
+				for (j = 0; j < p->totloop; j++) {
+					GridPaintMask *gpm = &gmask[p->loopstart + j];
+					const MLoop *l = &me->mloop[p->loopstart + j];
+					const MLoop *prev = ME_POLY_LOOP_PREV(me->mloop, p, j);
+					const MLoop *next = ME_POLY_LOOP_NEXT(me->mloop, p, j);
+
+					gpm->data[0] = avg;
+					gpm->data[1] = (paint_mask[l->v] +
+									paint_mask[next->v]) * 0.5f;
+					gpm->data[2] = (paint_mask[l->v] +
+									paint_mask[prev->v]) * 0.5f;
+					gpm->data[3] = paint_mask[l->v];
+				}
+			}
+		}
+
+		ret |= ED_SCULPT_MASK_LAYER_CALC_LOOP;
+	}
+
+	/* create vertex paint mask layer if there isn't one already */
+	if (!paint_mask) {
+		CustomData_add_layer(&me->vdata, CD_PAINT_MASK,
+							 CD_CALLOC, NULL, me->totvert);
+		ret |= ED_SCULPT_MASK_LAYER_CALC_VERT;
+	}
+
+	return ret;
+}
diff --git a/source/blender/editors/include/ED_sculpt.h b/source/blender/editors/include/ED_sculpt.h
index ab8a65e9ef9..8fcb228803b 100644
--- a/source/blender/editors/include/ED_sculpt.h
+++ b/source/blender/editors/include/ED_sculpt.h
@@ -46,15 +46,8 @@ void sculpt_get_redraw_planes(float planes[4][4], struct ARegion *ar,
                               struct RegionView3D *rv3d, struct Object *ob);
 void ED_sculpt_get_average_stroke(struct Object *ob, float stroke[3]);
 bool ED_sculpt_minmax(struct bContext *C, float min[3], float max[3]);
-int ED_sculpt_mask_layers_ensure(struct Object *ob,
-                                  struct MultiresModifierData *mmd);
 int do_sculpt_mask_box_select(struct ViewContext *vc, struct rcti *rect, bool select, bool extend);
 
-enum {
-	ED_SCULPT_MASK_LAYER_CALC_VERT = (1 << 0),
-	ED_SCULPT_MASK_LAYER_CALC_LOOP = (1 << 1)
-};
-
 /* paint_ops.c */
 void ED_operatortypes_paint(void);
 void ED_keymap_paint(struct wmKeyConfig *keyconf);
diff --git a/source/blender/editors/include/ED_util.h b/source/blender/editors/include/ED_util.h
index f268595ff52..6d9f1c4eda0 100644
--- a/source/blender/editors/include/ED_util.h
+++ b/source/blender/editors/include/ED_util.h
@@ -79,14 +79,6 @@ void undo_editmode_push(struct bContext *C, const char *name,
 
 void    undo_editmode_clear(void);
 
-/* crazyspace.c */
-float (*crazyspace_get_mapped_editverts(struct Scene *scene, struct Object *obedit))[3];
-void crazyspace_set_quats_editmesh(struct BMEditMesh *em, float (*origcos)[3], float (*mappedcos)[3], float (*quats)[4],
-                                   const bool use_select);
-void crazyspace_set_quats_mesh(struct Mesh *me, float (*origcos)[3], float (*mappedcos)[3], float (*quats)[4]);
-int sculpt_get_first_deform_matrices(struct Scene *scene, struct Object *ob, float (**deformmats)[3][3], float (**deformcos)[3]);
-void crazyspace_build_sculpt(struct Scene *scene, struct Object *ob, float (**deformmats)[3][3], float (**deformcos)[3]);
-
 /* cut-paste buffer free */
 void ED_clipboard_posebuf_free(void);
 
diff --git a/source/blender/editors/object/object_modifier.c b/source/blender/editors/object/object_modifier.c
index 5dfcbc69640..c24e7746abb 100644
--- a/source/blender/editors/object/object_modifier.c
+++ b/source/blender/editors/object/object_modifier.c
@@ -69,6 +69,7 @@
 #include "BKE_report.h"
 #include "BKE_object.h"
 #include "BKE_ocean.h"
+#include "BKE_paint.h"
 #include "BKE_particle.h"
 #include "BKE_softbody.h"
 #include "BKE_editmesh.h"
@@ -80,7 +81,6 @@
 #include "ED_armature.h"
 #include "ED_object.h"
 #include "ED_screen.h"
-#include "ED_sculpt.h"
 #include "ED_mesh.h"
 
 #include "WM_api.h"
diff --git a/source/blender/editors/sculpt_paint/sculpt.c b/source/blender/editors/sculpt_paint/sculpt.c
index 4a1a65832e6..3cd8cbab783 100644
--- a/source/blender/editors/sculpt_paint/sculpt.c
+++ b/source/blender/editors/sculpt_paint/sculpt.c
@@ -55,6 +55,7 @@
 #include "BKE_brush.h"
 #include "BKE_ccg.h"
 #include "BKE_context.h"
+#include "BKE_crazyspace.h"
 #include "BKE_depsgraph.h"
 #include "BKE_image.h"
 #include "BKE_key.h"
@@ -76,7 +77,6 @@
 #include "ED_object.h"
 #include "ED_screen.h"
 #include "ED_view3d.h"
-#include "ED_util.h" /* for crazyspace correction */
 #include "paint_intern.h"
 #include "sculpt_intern.h"
 
@@ -137,38 +137,6 @@ bool ED_sculpt_minmax(bContext *C, float min[3], float max[3])
 	}
 }
 
-/* Sculpt mode handles multires differently from regular meshes, but only if
- * it's the last modifier on the stack and it is not on the first level */
-MultiresModifierData *sculpt_multires_active(Scene *scene, Object *ob)
-{
-	Mesh *me = (Mesh *)ob->data;
-	ModifierData *md;
-	VirtualModifierData virtualModifierData;
-
-	if (ob->sculpt && ob->sculpt->bm) {
-		/* can't combine multires and dynamic topology */
-		return NULL;
-	}
-
-	if (!CustomData_get_layer(&me->ldata, CD_MDISPS)) {
-		/* multires can't work without displacement layer */
-		return NULL;
-	}
-
-	for (md = modifiers_getVirtualModifierList(ob, &virtualModifierData); md; md = md->next) {
-		if (md->type == eModifierType_Multires) {
-			MultiresModifierData *mmd = (MultiresModifierData *)md;
-
-			if (!modifier_isEnabled(scene, md, eModifierMode_Realtime))
-				continue;
-
-			if (mmd->sculptlvl > 0) return mmd;
-			else return NULL;
-		}
-	}
-
-	return NULL;
-}
 
 /* Check if there are any active modifiers in stack (used for flushing updates at enter/exit sculpt mode) */
 static bool sculpt_has_active_modifiers(Scene *scene, Object *ob)
@@ -187,35 +155,7 @@ static bool sculpt_has_active_modifiers(Scene *scene, Object *ob)
 	return 0;
 }
 
-/* Checks if there are any supported deformation modifiers active */
-static bool sculpt_modifiers_active(Scene *scene, Sculpt *sd, Object *ob)
-{
-	ModifierData *md;
-	Mesh *me = (Mesh *)ob->data;
-	MultiresModifierData *mmd = sculpt_multires_active(scene, ob);
-	VirtualModifierData virtualModifierData;
-
-	if (mmd || ob->sculpt->bm)
-		return 0;
-
-	/* non-locked shape keys could be handled in the same way as deformed mesh */
-	if ((ob->shapeflag & OB_SHAPE_LOCK) == 0 && me->key && ob->shapenr)
-		return 1;
-
-	md = modifiers_getVirtualModifierList(ob, &virtualModifierData);
-
-	/* exception for shape keys because we can edit those */
-	for (; md; md = md->next) {
-		ModifierTypeInfo *mti = modifierType_getInfo(md->type);
-		if (!modifier_isEnabled(scene, md, eModifierMode_Realtime)) continue;
-		if (md->type == eModifierType_ShapeKey) continue;
-
-		if (mti->type == eModifierTypeType_OnlyDeform) return 1;
-		else if ((sd->flags & SCULPT_ONLY_DEFORM) == 0) return 1;
-	}
 
-	return 0;
-}
 
 typedef enum StrokeFlags {
 	CLIP_X = 1,
@@ -3561,106 +3501,7 @@ static void sculpt_update_tex(const Scene *scene, Sculpt *sd, SculptSession *ss)
 	}
 }
 
-/**
- * \param need_mask So the DerivedMesh thats returned has mask data
- */
-void sculpt_update_mesh_elements(Scene *scene, Sculpt *sd, Object *ob,
-                                 bool need_pmap, bool need_mask)
-{
-	DerivedMesh *dm;
-	SculptSession *ss = ob->sculpt;
-	Mesh *me = ob->data;
-	MultiresModifierData *mmd = sculpt_multires_active(scene, ob);
-
-	ss->modifiers_active = sculpt_modifiers_active(scene, sd, ob);
-	ss->show_diffuse_color = (sd->flags & SCULPT_SHOW_DIFFUSE) != 0;
 
-	if (need_mask) {
-		if (mmd == NULL) {
-			if (!CustomData_has_layer(&me->vdata, CD_PAINT_MASK)) {
-				ED_sculpt_mask_layers_ensure(ob, NULL);
-			}
-		}
-		else {
-			if (!CustomData_has_layer(&me->ldata, CD_GRID_PAINT_MASK)) {
-#if 1
-				ED_sculpt_mask_layers_ensure(ob, mmd);
-#else				/* if we wanted to support adding mask data while multi-res painting, we would need to do this */
-				if ((ED_sculpt_mask_layers_ensure(ob, mmd) & ED_SCULPT_MASK_LAYER_CALC_LOOP)) {
-					/* remake the derived mesh */
-					ob->recalc |= OB_RECALC_DATA;
-					BKE_object_handle_update(scene, ob);
-				}
-#endif
-			}
-		}
-	}
-
-	/* BMESH ONLY --- at some point we should move sculpt code to use polygons only - but for now it needs tessfaces */
-	BKE_mesh_tessface_ensure(me);
-
-	if (!mmd) ss->kb = BKE_keyblock_from_object(ob);
-	else ss->kb = NULL;
-
-	/* needs to be called after we ensure tessface */
-	dm = mesh_get_derived_final(scene, ob, CD_MASK_BAREMESH);
-
-	if (mmd) {
-		ss->multires = mmd;
-		ss->totvert = dm->getNumVerts(dm);
-		ss->totpoly = dm->getNumPolys(dm);
-		ss->mvert = NULL;
-		ss->mpoly = NULL;
-		ss->mloop = NULL;
-		ss->face_normals = NULL;
-	}
-	else {
-		ss->totvert = me->totvert;
-		ss->totpoly = me->totpoly;
-		ss->mvert = me->mvert;
-		ss->mpoly = me->mpoly;
-		ss->mloop = me->mloop;
-		ss->face_normals = NULL;
-		ss->multires = NULL;
-		ss->vmask = CustomData_get_layer(&me->vdata, CD_PAINT_MASK);
-	}
-
-	ss->pbvh = dm->getPBVH(ob, dm);
-	ss->pmap = (need_pmap && dm->getPolyMap) ? dm->getPolyMap(ob, dm) : NULL;
-
-	pbvh_show_diffuse_color_set(ss->pbvh, ss->show_diffuse_color);
-
-	if (ss->modifiers_active) {
-		if (!ss->orig_cos) {
-			int a;
-
-			free_sculptsession_deformMats(ss);
-
-			ss->orig_cos = (ss->kb) ? BKE_key_convert_to_vertcos(ob, ss->kb) : BKE_mesh_vertexCos_get(me, NULL);
-
-			crazyspace_build_sculpt(scene, ob, &ss->deform_imats, &ss->deform_cos);
-			BKE_pbvh_apply_vertCos(ss->pbvh, ss->deform_cos);
-
-			for (a = 0; a < me->totvert; ++a) {
-				invert_m3(ss->deform_imats[a]);
-			}
-		}
-	}
-	else {
-		free_sculptsession_deformMats(ss);
-	}
-
-	/* if pbvh is deformed, key block is already applied to it */
-	if (ss->kb && !BKE_pbvh_isDeformed(ss->pbvh)) {
-		float (*vertCos)[3] = BKE_key_convert_to_vertcos(ob, ss->kb);
-
-		if (vertCos) {
-			/* apply shape keys coordinates to PBVH */
-			BKE_pbvh_apply_vertCos(ss->pbvh, vertCos);
-			MEM_freeN(vertCos);
-		}
-	}
-}
 
 int sculpt_mode_poll(bContext *C)
 {
@@ -5109,76 +4950,6 @@ static void sculpt_init_session(Scene *scene, Object *ob)
 	sculpt_update_mesh_elements(scene, scene->toolsettings->sculpt, ob, 0, false);
 }
 
-int ED_sculpt_mask_layers_ensure(Object *ob, MultiresModifierData *mmd)
-{
-	const float *paint_mask;
-	Mesh *me = ob->data;
-	int ret = 0;
-
-	paint_mask = CustomData_get_layer(&me->vdata, CD_PAINT_MASK);
-
-	/* if multires is active, create a grid paint mask layer if there
-	 * isn't one already */
-	if (mmd && !CustomData_has_layer(&me->ldata, CD_GRID_PAINT_MASK)) {
-		GridPaintMask *gmask;
-		int level = max_ii(1, mmd->sculptlvl);
-		int gridsize = BKE_ccg_gridsize(level);
-		int gridarea = gridsize * gridsize;
-		int i, j;
-
-		gmask = CustomData_add_layer(&me->ldata, CD_GRID_PAINT_MASK,
-		                             CD_CALLOC, NULL, me->totloop);
-
-		for (i = 0; i < me->totloop; i++) {
-			GridPaintMask *gpm = &gmask[i];
-
-			gpm->level = level;
-			gpm->data = MEM_callocN(sizeof(float) * gridarea,
-			                        "GridPaintMask.data");
-		}
-
-		/* if vertices already have mask, copy into multires data */
-		if (paint_mask) {
-			for (i = 0; i < me->totpoly; i++) {
-				const MPoly *p = &me->mpoly[i];
-				float avg = 0;
-
-				/* mask center */
-				for (j = 0; j < p->totloop; j++) {
-					const MLoop *l = &me->mloop[p->loopstart + j];
-					avg += paint_mask[l->v];
-				}
-				avg /= (float)p->totloop;
-
-				/* fill in multires mask corner */
-				for (j = 0; j < p->totloop; j++) {
-					GridPaintMask *gpm = &gmask[p->loopstart + j];
-					const MLoop *l = &me->mloop[p->loopstart + j];
-					const MLoop *prev = ME_POLY_LOOP_PREV(me->mloop, p, j);
-					const MLoop *next = ME_POLY_LOOP_NEXT(me->mloop, p, j);
-
-					gpm->data[0] = avg;
-					gpm->data[1] = (paint_mask[l->v] +
-					                paint_mask[next->v]) * 0.5f;
-					gpm->data[2] = (paint_mask[l->v] +
-					                paint_mask[prev->v]) * 0.5f;
-					gpm->data[3] = paint_mask[l->v];
-				}
-			}
-		}
-
-		ret |= ED_SCULPT_MASK_LAYER_CALC_LOOP;
-	}
-
-	/* create vertex paint mask layer if there isn't one already */
-	if (!paint_mask) {
-		CustomData_add_layer(&me->vdata, CD_PAINT_MASK,
-		                     CD_CALLOC, NULL, me->totvert);
-		ret |= ED_SCULPT_MASK_LAYER_CALC_VERT;
-	}
-
-	return ret;
-}
 
 static int sculpt_mode_toggle_exec(bContext *C, wmOperator *op)
 {
diff --git a/source/blender/editors/sculpt_paint/sculpt_intern.h b/source/blender/editors/sculpt_paint/sculpt_intern.h
index a4d2f0dc057..cd79f525d82 100644
--- a/source/blender/editors/sculpt_paint/sculpt_intern.h
+++ b/source/blender/editors/sculpt_paint/sculpt_intern.h
@@ -51,16 +51,11 @@ struct Sculpt;
 struct SculptStroke;
 struct SculptUndoNode;
 
-/* Interface */
-struct MultiresModifierData *sculpt_multires_active(struct Scene *scene, struct Object *ob);
-
 int sculpt_mode_poll(struct bContext *C);
 int sculpt_mode_poll_view3d(struct bContext *C);
 /* checks for a brush, not just sculpt mode */
 int sculpt_poll(struct bContext *C);
 int sculpt_poll_view3d(struct bContext *C);
-void sculpt_update_mesh_elements(struct Scene *scene, struct Sculpt *sd, struct Object *ob,
-                                 bool need_pmap, bool need_mask);
 
 /* Stroke */
 bool sculpt_stroke_get_location(bContext *C, float out[3], const float mouse[2]);
diff --git a/source/blender/editors/transform/transform_conversions.c b/source/blender/editors/transform/transform_conversions.c
index c3a8784b6d3..0685561fab9 100644
--- a/source/blender/editors/transform/transform_conversions.c
+++ b/source/blender/editors/transform/transform_conversions.c
@@ -64,6 +64,7 @@
 #include "BKE_armature.h"
 #include "BKE_constraint.h"
 #include "BKE_context.h"
+#include "BKE_crazyspace.h"
 #include "BKE_curve.h"
 #include "BKE_depsgraph.h"
 #include "BKE_fcurve.h"
@@ -104,7 +105,6 @@
 #include "ED_uvedit.h"
 #include "ED_clip.h"
 #include "ED_mask.h"
-#include "ED_util.h"  /* for crazyspace correction */
 
 #include "WM_api.h"  /* for WM_event_add_notifier to deal with stabilization nodes */
 #include "WM_types.h"
diff --git a/source/blender/editors/util/CMakeLists.txt b/source/blender/editors/util/CMakeLists.txt
index 95e01d8e454..3c051586282 100644
--- a/source/blender/editors/util/CMakeLists.txt
+++ b/source/blender/editors/util/CMakeLists.txt
@@ -40,7 +40,6 @@ set(SRC
 	editmode_undo.c
 	numinput.c
 	undo.c
-	crazyspace.c
 
 	util_intern.h
 	# general includes