/*
 * $Id$
 *
 * ***** 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) 2007 by Nicholas Bishop
 * All rights reserved.
 *
 * The Original Code is: all of this file.
 *
 * Contributor(s): none yet.
 *
 * ***** END GPL LICENSE BLOCK *****
 */

#include "MEM_guardedalloc.h"

#include "DNA_mesh_types.h"
#include "DNA_meshdata_types.h"
#include "DNA_object_types.h"
#include "DNA_scene_types.h"

#include "BLI_blenlib.h"
#include "BLI_math.h"
#include "BLI_pbvh.h"

#include "BKE_cdderivedmesh.h"
#include "BKE_mesh.h"
#include "BKE_modifier.h"
#include "BKE_multires.h"
#include "BKE_paint.h"
#include "BKE_scene.h"
#include "BKE_subsurf.h"
#include "BKE_utildefines.h"

#include "CCGSubSurf.h"

#include <math.h>
#include <string.h>

/* MULTIRES MODIFIER */
static const int multires_max_levels = 13;
static const int multires_grid_tot[] = {0, 4, 9, 25, 81, 289, 1089, 4225, 16641, 66049, 263169, 1050625, 4198401, 16785409};
static const int multires_side_tot[] = {0, 2, 3, 5,  9,  17,  33,   65,   129,   257,   513,    1025,    2049,    4097};

static void multires_mvert_to_ss(DerivedMesh *dm, MVert *mvert);
static void multiresModifier_disp_run(DerivedMesh *dm, Mesh *me, int invert, int add, DMGridData **oldGridData, int totlvl);

DerivedMesh *get_multires_dm(Scene *scene, MultiresModifierData *mmd, Object *ob)
{
	ModifierData *md= (ModifierData *)mmd;
	ModifierTypeInfo *mti = modifierType_getInfo(md->type);
	DerivedMesh *tdm = mesh_get_derived_deform(scene, ob, CD_MASK_BAREMESH);
	DerivedMesh *dm;

	dm = mti->applyModifier(md, ob, tdm, 0, 1);
	if (dm == tdm) {
		dm = CDDM_copy(tdm);
	}

	return dm;
}

MultiresModifierData *find_multires_modifier_before(Scene *scene, ModifierData *lastmd)
{
	ModifierData *md;

	for(md = lastmd; md; md = md->prev) {
		if(md->type == eModifierType_Multires) {
			if (modifier_isEnabled(scene, md, eModifierMode_Realtime))
				return (MultiresModifierData*)md;
		}
	}

	return NULL;
}

static int multires_get_level(Object *ob, MultiresModifierData *mmd, int render)
{
	if(render)
		return (mmd->modifier.scene)? get_render_subsurf_level(&mmd->modifier.scene->r, mmd->renderlvl): mmd->renderlvl;
	else if(ob->mode == OB_MODE_SCULPT)
		return mmd->sculptlvl;
	else
		return (mmd->modifier.scene)? get_render_subsurf_level(&mmd->modifier.scene->r, mmd->lvl): mmd->lvl;
}

static void multires_set_tot_level(Object *ob, MultiresModifierData *mmd, int lvl)
{
	mmd->totlvl = lvl;

	if(ob->mode != OB_MODE_SCULPT)
		mmd->lvl = CLAMPIS(MAX2(mmd->lvl, lvl), 0, mmd->totlvl);

	mmd->sculptlvl = CLAMPIS(MAX2(mmd->sculptlvl, lvl), 0, mmd->totlvl);
	mmd->renderlvl = CLAMPIS(MAX2(mmd->renderlvl, lvl), 0, mmd->totlvl);
}

static void multires_dm_mark_as_modified(DerivedMesh *dm)
{
	CCGDerivedMesh *ccgdm = (CCGDerivedMesh*)dm;
	ccgdm->multires.modified = 1;
}

void multires_mark_as_modified(Object *ob)
{
	if(ob && ob->derivedFinal)
		multires_dm_mark_as_modified(ob->derivedFinal);
}

void multires_force_update(Object *ob)
{
	if(ob) {
		if(ob->derivedFinal) {
			ob->derivedFinal->needsFree =1;
			ob->derivedFinal->release(ob->derivedFinal);
			ob->derivedFinal = NULL;
		}
		if(ob->sculpt && ob->sculpt->pbvh) {
			BLI_pbvh_free(ob->sculpt->pbvh);
			ob->sculpt->pbvh= NULL;
		}
	}
}

void multires_force_external_reload(Object *ob)
{
	Mesh *me = get_mesh(ob);

	CustomData_external_reload(&me->fdata, &me->id, CD_MASK_MDISPS, me->totface);
	multires_force_update(ob);
}

void multires_force_render_update(Object *ob)
{
	if(ob && (ob->mode & OB_MODE_SCULPT) && modifiers_findByType(ob, eModifierType_Multires))
		multires_force_update(ob);
}

/* XXX */
#if 0
void multiresModifier_join(Object *ob)
{
	Base *base = NULL;
	int highest_lvl = 0;

	/* First find the highest level of subdivision */
	base = FIRSTBASE;
	while(base) {
		if(TESTBASELIB_BGMODE(v3d, scene, base) && base->object->type==OB_MESH) {
			ModifierData *md;
			for(md = base->object->modifiers.first; md; md = md->next) {
				if(md->type == eModifierType_Multires) {
					int totlvl = ((MultiresModifierData*)md)->totlvl;
					if(totlvl > highest_lvl)
						highest_lvl = totlvl;

					/* Ensure that all updates are processed */
					multires_force_update(base->object);
				}
			}
		}
		base = base->next;
	}

	/* No multires meshes selected */
	if(highest_lvl == 0)
		return;

	/* Subdivide all the displacements to the highest level */
	base = FIRSTBASE;
	while(base) {
		if(TESTBASELIB_BGMODE(v3d, scene, base) && base->object->type==OB_MESH) {
			ModifierData *md = NULL;
			MultiresModifierData *mmd = NULL;

			for(md = base->object->modifiers.first; md; md = md->next) {
				if(md->type == eModifierType_Multires)
					mmd = (MultiresModifierData*)md;
			}

			/* If the object didn't have multires enabled, give it a new modifier */
			if(!mmd) {
				md = base->object->modifiers.first;
				
				while(md && modifierType_getInfo(md->type)->type == eModifierTypeType_OnlyDeform)
					md = md->next;
				
				mmd = (MultiresModifierData*)modifier_new(eModifierType_Multires);
				BLI_insertlinkbefore(&base->object->modifiers, md, mmd);
				modifier_unique_name(&base->object->modifiers, mmd);
			}

			if(mmd)
				multiresModifier_subdivide(mmd, base->object, highest_lvl - mmd->totlvl, 0, 0);
		}
		base = base->next;
	}
}
#endif

int multiresModifier_reshapeFromDM(Scene *scene, MultiresModifierData *mmd,
				Object *ob, DerivedMesh *srcdm)
{
	DerivedMesh *mrdm = get_multires_dm (scene, mmd, ob);

	if(mrdm && srcdm && mrdm->getNumVerts(mrdm) == srcdm->getNumVerts(srcdm)) {
		multires_mvert_to_ss(mrdm, srcdm->getVertArray(srcdm));

		multires_dm_mark_as_modified(mrdm);
		multires_force_update(ob);

		mrdm->release(mrdm);

		return 1;
	}

	mrdm->release(mrdm);

	return 0;
}

/* Returns 1 on success, 0 if the src's totvert doesn't match */
int multiresModifier_reshape(Scene *scene, MultiresModifierData *mmd, Object *dst, Object *src)
{
	DerivedMesh *srcdm = mesh_get_derived_final(scene, src, CD_MASK_BAREMESH);
	return multiresModifier_reshapeFromDM(scene, mmd, dst, srcdm);
}

int multiresModifier_reshapeFromDeformMod(Scene *scene, MultiresModifierData *mmd,
				Object *ob, ModifierData *md)
{
	ModifierTypeInfo *mti = modifierType_getInfo(md->type);
	DerivedMesh *dm, *ndm;
	int numVerts, result;
	float (*deformedVerts)[3];

	if(multires_get_level(ob, mmd, 0) == 0)
		return 0;

	/* Create DerivedMesh for deformation modifier */
	dm = get_multires_dm(scene, mmd, ob);
	numVerts= dm->getNumVerts(dm);
	deformedVerts= MEM_callocN(sizeof(float)*numVerts*3, "multiresReshape_deformVerts");

	dm->getVertCos(dm, deformedVerts);
	mti->deformVerts(md, ob, dm, deformedVerts, numVerts, 0, 0);

	ndm= CDDM_copy(dm);
	CDDM_apply_vert_coords(ndm, deformedVerts);

	MEM_freeN(deformedVerts);
	dm->release(dm);

	/* Reshaping */
	result= multiresModifier_reshapeFromDM(scene, mmd, ob, ndm);

	/* Cleanup */
	ndm->release(ndm);

	return result;
}

static void multires_set_tot_mdisps(Mesh *me, int lvl)
{
	MDisps *mdisps= CustomData_get_layer(&me->fdata, CD_MDISPS);
	int i;

	if(mdisps) {
		for(i = 0; i < me->totface; i++) {
			if(mdisps[i].totdisp == 0) {
				int nvert = (me->mface[i].v4)? 4: 3;
				mdisps[i].totdisp = multires_grid_tot[lvl]*nvert;
			}
		}
	}
}

static void multires_reallocate_mdisps(Mesh *me, MDisps *mdisps, int lvl)
{
	int i;

	/* reallocate displacements to be filled in */
	for(i = 0; i < me->totface; ++i) {
		int nvert = (me->mface[i].v4)? 4: 3;
		int totdisp = multires_grid_tot[lvl]*nvert;
		float (*disps)[3] = MEM_callocN(sizeof(float) * 3 * totdisp, "multires disps");

		if(mdisps[i].disps)
			MEM_freeN(mdisps[i].disps);

		mdisps[i].disps = disps;
		mdisps[i].totdisp = totdisp;
	}
}

static void column_vectors_to_mat3(float mat[][3], float v1[3], float v2[3], float v3[3])
{
	copy_v3_v3(mat[0], v1);
	copy_v3_v3(mat[1], v2);
	copy_v3_v3(mat[2], v3);
}

static void multires_copy_grid(float (*gridA)[3], float (*gridB)[3], int sizeA, int sizeB)
{
	int x, y, j, skip;

	if(sizeA > sizeB) {
		skip = (sizeA-1)/(sizeB-1);

		for(j = 0, y = 0; y < sizeB; y++)
			for(x = 0; x < sizeB; x++, j++)
				copy_v3_v3(gridA[y*skip*sizeA + x*skip], gridB[j]);
	}
	else {
		skip = (sizeB-1)/(sizeA-1);

		for(j = 0, y = 0; y < sizeA; y++)
			for(x = 0; x < sizeA; x++, j++)
				copy_v3_v3(gridA[j], gridB[y*skip*sizeB + x*skip]);
	}
}

static void multires_copy_dm_grid(DMGridData *gridA, DMGridData *gridB, int sizeA, int sizeB)
{
	int x, y, j, skip;

	if(sizeA > sizeB) {
		skip = (sizeA-1)/(sizeB-1);

		for(j = 0, y = 0; y < sizeB; y++)
			for(x = 0; x < sizeB; x++, j++)
				copy_v3_v3(gridA[y*skip*sizeA + x*skip].co, gridB[j].co);
	}
	else {
		skip = (sizeB-1)/(sizeA-1);

		for(j = 0, y = 0; y < sizeA; y++)
			for(x = 0; x < sizeA; x++, j++)
				copy_v3_v3(gridA[j].co, gridB[y*skip*sizeB + x*skip].co);
	}
}

/* direction=1 for delete higher, direction=0 for lower (not implemented yet) */
void multiresModifier_del_levels(MultiresModifierData *mmd, Object *ob, int direction)
{
	Mesh *me = get_mesh(ob);
	int lvl = multires_get_level(ob, mmd, 0);
	int levels = mmd->totlvl - lvl;
	MDisps *mdisps;

	multires_set_tot_mdisps(me, mmd->totlvl);
	CustomData_external_read(&me->fdata, &me->id, CD_MASK_MDISPS, me->totface);
	mdisps= CustomData_get_layer(&me->fdata, CD_MDISPS);

	multires_force_update(ob);

	if(mdisps && levels > 0 && direction == 1) {
		if(lvl > 0) {
			int nsize = multires_side_tot[lvl];
			int hsize = multires_side_tot[mmd->totlvl];
			int i;

			for(i = 0; i < me->totface; ++i) {
				MDisps *mdisp= &mdisps[i];
				float (*disps)[3], (*ndisps)[3], (*hdisps)[3];
				int nvert = (me->mface[i].v4)? 4: 3;
				int totdisp = multires_grid_tot[lvl]*nvert;
				int S;

				disps = MEM_callocN(sizeof(float) * 3 * totdisp, "multires disps");

				ndisps = disps;
				hdisps = mdisp->disps;

				for(S = 0; S < nvert; S++) {
					multires_copy_grid(ndisps, hdisps, nsize, hsize);

					ndisps += nsize*nsize;
					hdisps += hsize*hsize;
				}

				MEM_freeN(mdisp->disps);
				mdisp->disps = disps;
				mdisp->totdisp = totdisp;
			}
		}
		else {
			CustomData_external_remove(&me->fdata, &me->id, CD_MDISPS, me->totface);
			CustomData_free_layer_active(&me->fdata, CD_MDISPS, me->totface);
		}
	}

	multires_set_tot_level(ob, mmd, lvl);
}

static DerivedMesh *multires_dm_create_local(Object *ob, DerivedMesh *dm, int lvl, int totlvl, int simple)
{
	MultiresModifierData mmd;

	memset(&mmd, 0, sizeof(MultiresModifierData));
	mmd.lvl = lvl;
	mmd.sculptlvl = lvl;
	mmd.renderlvl = lvl;
	mmd.totlvl = totlvl;
	mmd.simple = simple;

	return multires_dm_create_from_derived(&mmd, 1, dm, ob, 0, 0);
}

static DerivedMesh *subsurf_dm_create_local(Object *ob, DerivedMesh *dm, int lvl, int simple, int optimal)
{
	SubsurfModifierData smd;

	memset(&smd, 0, sizeof(SubsurfModifierData));
	smd.levels = smd.renderLevels = lvl;
	smd.flags |= eSubsurfModifierFlag_SubsurfUv;
	if(simple)
		smd.subdivType = ME_SIMPLE_SUBSURF;
	if(optimal)
		smd.flags |= eSubsurfModifierFlag_ControlEdges;

	return subsurf_make_derived_from_derived(dm, &smd, 0, NULL, 0, 0);
}

void multiresModifier_subdivide(MultiresModifierData *mmd, Object *ob, int updateblock, int simple)
{
	Mesh *me = ob->data;
	MDisps *mdisps;
	int lvl= mmd->totlvl;
	int totlvl= mmd->totlvl+1;

	if(totlvl > multires_max_levels)
		return;

	multires_force_update(ob);

	mdisps = CustomData_get_layer(&me->fdata, CD_MDISPS);
	if(!mdisps)
		mdisps = CustomData_add_layer(&me->fdata, CD_MDISPS, CD_DEFAULT, NULL, me->totface);

	if(mdisps->disps && !updateblock && totlvl > 1) {
		/* upsample */
		DerivedMesh *lowdm, *cddm, *highdm;
		DMGridData **highGridData, **lowGridData, **subGridData;
		CCGSubSurf *ss;
		int i, numGrids, highGridSize, lowGridSize;

		/* create subsurf DM from original mesh at high level */
		cddm = CDDM_from_mesh(me, NULL);
		DM_set_only_copy(cddm, CD_MASK_BAREMESH);
		highdm = subsurf_dm_create_local(ob, cddm, totlvl, simple, 0);

		/* create multires DM from original mesh at low level */
		lowdm = multires_dm_create_local(ob, cddm, lvl, lvl, simple);
		cddm->release(cddm);

		/* copy subsurf grids and replace them with low displaced grids */
		numGrids = highdm->getNumGrids(highdm);
		highGridSize = highdm->getGridSize(highdm);
		highGridData = highdm->getGridData(highdm);
		lowGridSize = lowdm->getGridSize(lowdm);
		lowGridData = lowdm->getGridData(lowdm);

		subGridData = MEM_callocN(sizeof(float*)*numGrids, "subGridData*");

		for(i = 0; i < numGrids; ++i) {
			/* backup subsurf grids */
			subGridData[i] = MEM_callocN(sizeof(DMGridData)*highGridSize*highGridSize, "subGridData");
			memcpy(subGridData[i], highGridData[i], sizeof(DMGridData)*highGridSize*highGridSize);

			/* overwrite with current displaced grids */
			multires_copy_dm_grid(highGridData[i], lowGridData[i], highGridSize, lowGridSize);
		}

		/* low lower level dm no longer needed at this point */
		lowdm->release(lowdm);

		/* subsurf higher levels again with displaced data */
		ss= ((CCGDerivedMesh*)highdm)->ss;
		ccgSubSurf_updateFromFaces(ss, lvl, NULL, 0);
		ccgSubSurf_updateLevels(ss, lvl, NULL, 0);

		/* reallocate displacements */
		multires_reallocate_mdisps(me, mdisps, totlvl); 

		/* compute displacements */
		multiresModifier_disp_run(highdm, me, 1, 0, subGridData, totlvl);

		/* free */
		highdm->release(highdm);
		for(i = 0; i < numGrids; ++i)
			MEM_freeN(subGridData[i]);
		MEM_freeN(subGridData);
	}
	else {
		/* only reallocate, nothing to upsample */
		multires_reallocate_mdisps(me, mdisps, totlvl); 
	}

	multires_set_tot_level(ob, mmd, totlvl);
}

static void grid_tangent(int gridSize, int index, int x, int y, int axis, DMGridData **gridData, float t[3])
{
	if(axis == 0) {
		if(x == gridSize - 1) {
			if(y == gridSize - 1)
				sub_v3_v3v3(t, gridData[index][x + gridSize*(y - 1)].co, gridData[index][x - 1 + gridSize*(y - 1)].co);
			else
				sub_v3_v3v3(t, gridData[index][x + gridSize*y].co, gridData[index][x - 1 + gridSize*y].co);
		}
		else
			sub_v3_v3v3(t, gridData[index][x + 1 + gridSize*y].co, gridData[index][x + gridSize*y].co);
	}
	else if(axis == 1) {
		if(y == gridSize - 1) {
			if(x == gridSize - 1)
				sub_v3_v3v3(t, gridData[index][x - 1 + gridSize*y].co, gridData[index][x - 1 + gridSize*(y - 1)].co);
			else
				sub_v3_v3v3(t, gridData[index][x + gridSize*y].co, gridData[index][x + gridSize*(y - 1)].co);
		}
		else
			sub_v3_v3v3(t, gridData[index][x + gridSize*(y + 1)].co, gridData[index][x + gridSize*y].co);
	}
}

static void multiresModifier_disp_run(DerivedMesh *dm, Mesh *me, int invert, int add, DMGridData **oldGridData, int totlvl)
{
	CCGDerivedMesh *ccgdm = (CCGDerivedMesh*)dm;
	DMGridData **gridData, **subGridData;
	MFace *mface = me->mface;
	MDisps *mdisps = CustomData_get_layer(&me->fdata, CD_MDISPS);
	int *gridOffset;
	int i, numGrids, gridSize, dGridSize, dSkip;

	if(!mdisps) {
		if(invert)
			mdisps = CustomData_add_layer(&me->fdata, CD_MDISPS, CD_DEFAULT, NULL, me->totface);
		else
			return;
	}

	numGrids = dm->getNumGrids(dm);
	gridSize = dm->getGridSize(dm);
	gridData = dm->getGridData(dm);
	gridOffset = dm->getGridOffset(dm);
	subGridData = (oldGridData)? oldGridData: gridData;

	dGridSize = multires_side_tot[totlvl];
	dSkip = (dGridSize-1)/(gridSize-1);

	#pragma omp parallel for private(i) if(me->totface*gridSize*gridSize*4 >= CCG_OMP_LIMIT)
	for(i = 0; i < me->totface; ++i) {
		const int numVerts = mface[i].v4 ? 4 : 3;
		MDisps *mdisp = &mdisps[i];
		int S, x, y, gIndex = gridOffset[i];

		/* when adding new faces in edit mode, need to allocate disps */
		if(!mdisp->disps)
		#pragma omp critical
		{
			multires_reallocate_mdisps(me, mdisps, totlvl);
		}

		for(S = 0; S < numVerts; ++S, ++gIndex) {
			DMGridData *grid = gridData[gIndex];
			DMGridData *subgrid = subGridData[gIndex];
			float (*dispgrid)[3] = &mdisp->disps[S*dGridSize*dGridSize];

			for(y = 0; y < gridSize; y++) {
				for(x = 0; x < gridSize; x++) {
					float *co = grid[x + y*gridSize].co;
					float *sco = subgrid[x + y*gridSize].co;
					float *no = subgrid[x + y*gridSize].no;
					float *data = dispgrid[dGridSize*y*dSkip + x*dSkip];
					float mat[3][3], tx[3], ty[3], disp[3], d[3];

					/* construct tangent space matrix */
					grid_tangent(gridSize, gIndex, x, y, 0, subGridData, tx);
					normalize_v3(tx);

					grid_tangent(gridSize, gIndex, x, y, 1, subGridData, ty);
					normalize_v3(ty);

					//mul_v3_fl(tx, 1.0f/(gridSize-1));
					//mul_v3_fl(ty, 1.0f/(gridSize-1));
					//cross_v3_v3v3(no, tx, ty);

					column_vectors_to_mat3(mat, tx, ty, no);

					if(!invert) {
						/* convert to object space and add */
						mul_v3_m3v3(disp, mat, data);
						add_v3_v3v3(co, sco, disp);
					}
					else if(!add) {
						/* convert difference to tangent space */
						sub_v3_v3v3(disp, co, sco);
						invert_m3(mat);
						mul_v3_m3v3(data, mat, disp);
					}
					else {
						/* convert difference to tangent space */
						invert_m3(mat);
						mul_v3_m3v3(d, mat, co);
						add_v3_v3(data, d);
					}
				}
			}
		}
	}

	if(!invert) {
		ccgSubSurf_stitchFaces(ccgdm->ss, 0, NULL, 0);
		ccgSubSurf_updateNormals(ccgdm->ss, NULL, 0);
	}
}

static void multiresModifier_update(DerivedMesh *dm)
{
	CCGDerivedMesh *ccgdm= (CCGDerivedMesh*)dm;
	Object *ob;
	Mesh *me;
	MDisps *mdisps;
	MultiresModifierData *mmd;

	ob = ccgdm->multires.ob;
	me = ccgdm->multires.ob->data;
	mmd = ccgdm->multires.mmd;
	multires_set_tot_mdisps(me, mmd->totlvl);
	CustomData_external_read(&me->fdata, &me->id, CD_MASK_MDISPS, me->totface);
	mdisps = CustomData_get_layer(&me->fdata, CD_MDISPS);

	if(mdisps) {
		int lvl = ccgdm->multires.lvl;
		int totlvl = ccgdm->multires.totlvl;
		
		if(lvl < totlvl) {
			Mesh *me = ob->data;
			DerivedMesh *lowdm, *cddm, *highdm;
			DMGridData **highGridData, **lowGridData, **subGridData, **gridData, *diffGrid;
			CCGSubSurf *ss;
			int i, j, numGrids, highGridSize, lowGridSize;

			/* create subsurf DM from original mesh at high level */
			if (ob->derivedDeform) cddm = CDDM_copy(ob->derivedDeform);
			else cddm = CDDM_from_mesh(me, NULL);
			DM_set_only_copy(cddm, CD_MASK_BAREMESH);

			highdm = subsurf_dm_create_local(ob, cddm, totlvl, mmd->simple, 0);

			/* create multires DM from original mesh and displacements */
			lowdm = multires_dm_create_local(ob, cddm, lvl, totlvl, mmd->simple);
			cddm->release(cddm);

			/* gather grid data */
			numGrids = highdm->getNumGrids(highdm);
			highGridSize = highdm->getGridSize(highdm);
			highGridData = highdm->getGridData(highdm);
			lowGridSize = lowdm->getGridSize(lowdm);
			lowGridData = lowdm->getGridData(lowdm);
			gridData = dm->getGridData(dm);

			subGridData = MEM_callocN(sizeof(DMGridData*)*numGrids, "subGridData*");
			diffGrid = MEM_callocN(sizeof(DMGridData)*lowGridSize*lowGridSize, "diff");

			for(i = 0; i < numGrids; ++i) {
				/* backup subsurf grids */
				subGridData[i] = MEM_callocN(sizeof(DMGridData)*highGridSize*highGridSize, "subGridData");
				memcpy(subGridData[i], highGridData[i], sizeof(DMGridData)*highGridSize*highGridSize);

				/* write difference of subsurf and displaced low level into high subsurf */
				for(j = 0; j < lowGridSize*lowGridSize; ++j)
					sub_v3_v3v3(diffGrid[j].co, gridData[i][j].co, lowGridData[i][j].co);

				multires_copy_dm_grid(highGridData[i], diffGrid, highGridSize, lowGridSize);
			}

			/* lower level dm no longer needed at this point */
			MEM_freeN(diffGrid);
			lowdm->release(lowdm);

			/* subsurf higher levels again with difference of coordinates */
			ss= ((CCGDerivedMesh*)highdm)->ss;
			ccgSubSurf_updateFromFaces(ss, lvl, NULL, 0);
			ccgSubSurf_updateLevels(ss, lvl, NULL, 0);

			/* add to displacements */
			multiresModifier_disp_run(highdm, me, 1, 1, subGridData, mmd->totlvl);

			/* free */
			highdm->release(highdm);
			for(i = 0; i < numGrids; ++i)
				MEM_freeN(subGridData[i]);
			MEM_freeN(subGridData);
		}
		else {
			DerivedMesh *cddm, *subdm;

			if (ob->derivedDeform) cddm = CDDM_copy(ob->derivedDeform);
			else cddm = CDDM_from_mesh(me, NULL);
			DM_set_only_copy(cddm, CD_MASK_BAREMESH);

			subdm = subsurf_dm_create_local(ob, cddm, mmd->totlvl, mmd->simple, 0);
			cddm->release(cddm);

			multiresModifier_disp_run(dm, me, 1, 0, subdm->getGridData(subdm), mmd->totlvl);

			subdm->release(subdm);
		}
	}
}

void multires_stitch_grids(Object *ob)
{
	/* utility for smooth brush */
	if(ob && ob->derivedFinal) {
		CCGDerivedMesh *ccgdm = (CCGDerivedMesh*)ob->derivedFinal;
		CCGFace **faces;
		int totface;

		if(ccgdm->pbvh) {
			BLI_pbvh_get_grid_updates(ccgdm->pbvh, 0, (void***)&faces, &totface);

			if(totface) {
				ccgSubSurf_stitchFaces(ccgdm->ss, 0, faces, totface);
				MEM_freeN(faces);
			}
		}
	}
}

DerivedMesh *multires_dm_create_from_derived(MultiresModifierData *mmd, int local_mmd, DerivedMesh *dm, Object *ob,
							int useRenderParams, int isFinalCalc)
{
	Mesh *me= ob->data;
	DerivedMesh *result;
	CCGDerivedMesh *ccgdm;
	DMGridData **gridData, **subGridData;
	int lvl= multires_get_level(ob, mmd, useRenderParams);
	int i, gridSize, numGrids;

	if(lvl == 0)
		return dm;

	result = subsurf_dm_create_local(ob, dm, lvl,
		mmd->simple, mmd->flags & eMultiresModifierFlag_ControlEdges);

	if(!local_mmd) {
		ccgdm = (CCGDerivedMesh*)result;

		ccgdm->multires.ob = ob;
		ccgdm->multires.mmd = mmd;
		ccgdm->multires.local_mmd = local_mmd;
		ccgdm->multires.lvl = lvl;
		ccgdm->multires.totlvl = mmd->totlvl;
		ccgdm->multires.modified = 0;
		ccgdm->multires.update = multiresModifier_update;
	}

	numGrids = result->getNumGrids(result);
	gridSize = result->getGridSize(result);
	gridData = result->getGridData(result);

	subGridData = MEM_callocN(sizeof(DMGridData*)*numGrids, "subGridData*");

	for(i = 0; i < numGrids; i++) {
		subGridData[i] = MEM_callocN(sizeof(DMGridData)*gridSize*gridSize, "subGridData");
		memcpy(subGridData[i], gridData[i], sizeof(DMGridData)*gridSize*gridSize);
	}

	multires_set_tot_mdisps(me, mmd->totlvl);
	CustomData_external_read(&me->fdata, &me->id, CD_MASK_MDISPS, me->totface);
	multiresModifier_disp_run(result, ob->data, 0, 0, subGridData, mmd->totlvl);

	for(i = 0; i < numGrids; i++)
		MEM_freeN(subGridData[i]);
	MEM_freeN(subGridData);

	return result;
}

/**** Old Multires code ****
***************************/

/* Adapted from sculptmode.c */
static void old_mdisps_bilinear(float out[3], float (*disps)[3], int st, float u, float v)
{
	int x, y, x2, y2;
	const int st_max = st - 1;
	float urat, vrat, uopp;
	float d[4][3], d2[2][3];

	if(u < 0)
		u = 0;
	else if(u >= st)
		u = st_max;
	if(v < 0)
		v = 0;
	else if(v >= st)
		v = st_max;

	x = floor(u);
	y = floor(v);
	x2 = x + 1;
	y2 = y + 1;

	if(x2 >= st) x2 = st_max;
	if(y2 >= st) y2 = st_max;
	
	urat = u - x;
	vrat = v - y;
	uopp = 1 - urat;

	mul_v3_v3fl(d[0], disps[y * st + x], uopp);
	mul_v3_v3fl(d[1], disps[y * st + x2], urat);
	mul_v3_v3fl(d[2], disps[y2 * st + x], uopp);
	mul_v3_v3fl(d[3], disps[y2 * st + x2], urat);

	add_v3_v3v3(d2[0], d[0], d[1]);
	add_v3_v3v3(d2[1], d[2], d[3]);
	mul_v3_fl(d2[0], 1 - vrat);
	mul_v3_fl(d2[1], vrat);

	add_v3_v3v3(out, d2[0], d2[1]);
}

static void old_mdisps_rotate(int S, int newside, int oldside, int x, int y, float *u, float *v)
{
	float offset = oldside*0.5f - 0.5f;

	if(S == 1) { *u= offset + x; *v = offset - y; }
	if(S == 2) { *u= offset + y; *v = offset + x; }
	if(S == 3) { *u= offset - x; *v = offset + y; }
	if(S == 0) { *u= offset - y; *v = offset - x; }
}

static void old_mdisps_convert(MFace *mface, MDisps *mdisp)
{
	int newlvl = log(sqrt(mdisp->totdisp)-1)/log(2);
	int oldlvl = newlvl+1;
	int oldside = multires_side_tot[oldlvl];
	int newside = multires_side_tot[newlvl];
	int nvert = (mface->v4)? 4: 3;
	int newtotdisp = multires_grid_tot[newlvl]*nvert;
	int x, y, S;
	float (*disps)[3], (*out)[3], u, v;

	disps = MEM_callocN(sizeof(float) * 3 * newtotdisp, "multires disps");

	out = disps;
	for(S = 0; S < nvert; S++) {
		for(y = 0; y < newside; ++y) {
			for(x = 0; x < newside; ++x, ++out) {
				old_mdisps_rotate(S, newside, oldside, x, y, &u, &v);
				old_mdisps_bilinear(*out, mdisp->disps, oldside, u, v);

				if(S == 1) { (*out)[1]= -(*out)[1]; }
				else if(S == 2) { SWAP(float, (*out)[0], (*out)[1]); }
				else if(S == 3) { (*out)[0]= -(*out)[0]; }
				else if(S == 0) { SWAP(float, (*out)[0], (*out)[1]); (*out)[0]= -(*out)[0]; (*out)[1]= -(*out)[1]; };
			}
		}
	}

	MEM_freeN(mdisp->disps);

	mdisp->totdisp= newtotdisp;
	mdisp->disps= disps;
}

void multires_load_old_250(Mesh *me)
{
	MDisps *mdisps;
	int a;

	mdisps= CustomData_get_layer(&me->fdata, CD_MDISPS);

	if(mdisps) {
		for(a=0; a<me->totface; a++)
			if(mdisps[a].totdisp)
				old_mdisps_convert(&me->mface[a], &mdisps[a]);
	}
}

/* Does not actually free lvl itself */
static void multires_free_level(MultiresLevel *lvl)
{
	if(lvl) {
		if(lvl->faces) MEM_freeN(lvl->faces);
		if(lvl->edges) MEM_freeN(lvl->edges);
		if(lvl->colfaces) MEM_freeN(lvl->colfaces);
	}
}

void multires_free(Multires *mr)
{
	if(mr) {
		MultiresLevel* lvl= mr->levels.first;

		/* Free the first-level data */
		if(lvl) {
			CustomData_free(&mr->vdata, lvl->totvert);
			CustomData_free(&mr->fdata, lvl->totface);
			if(mr->edge_flags)
				MEM_freeN(mr->edge_flags);
			if(mr->edge_creases)
				MEM_freeN(mr->edge_creases);
		}

		while(lvl) {
			multires_free_level(lvl);			
			lvl= lvl->next;
		}

		MEM_freeN(mr->verts);

		BLI_freelistN(&mr->levels);

		MEM_freeN(mr);
	}
}

static void create_old_vert_face_map(ListBase **map, IndexNode **mem, const MultiresFace *mface,
					 const int totvert, const int totface)
{
	int i,j;
	IndexNode *node = NULL;
	
	(*map) = MEM_callocN(sizeof(ListBase) * totvert, "vert face map");
	(*mem) = MEM_callocN(sizeof(IndexNode) * totface*4, "vert face map mem");
	node = *mem;
	
	/* Find the users */
	for(i = 0; i < totface; ++i){
		for(j = 0; j < (mface[i].v[3]?4:3); ++j, ++node) {
			node->index = i;
			BLI_addtail(&(*map)[mface[i].v[j]], node);
		}
	}
}

static void create_old_vert_edge_map(ListBase **map, IndexNode **mem, const MultiresEdge *medge,
					 const int totvert, const int totedge)
{
	int i,j;
	IndexNode *node = NULL;
	
	(*map) = MEM_callocN(sizeof(ListBase) * totvert, "vert edge map");
	(*mem) = MEM_callocN(sizeof(IndexNode) * totedge*2, "vert edge map mem");
	node = *mem;
	
	/* Find the users */
	for(i = 0; i < totedge; ++i){
		for(j = 0; j < 2; ++j, ++node) {
			node->index = i;
			BLI_addtail(&(*map)[medge[i].v[j]], node);
		}
	}
}

static MultiresFace *find_old_face(ListBase *map, MultiresFace *faces, int v1, int v2, int v3, int v4)
{
	IndexNode *n1;
	int v[4] = {v1, v2, v3, v4}, i, j;

	for(n1 = map[v1].first; n1; n1 = n1->next) {
		int fnd[4] = {0, 0, 0, 0};

		for(i = 0; i < 4; ++i) {
			for(j = 0; j < 4; ++j) {
				if(v[i] == faces[n1->index].v[j])
					fnd[i] = 1;
			}
		}

		if(fnd[0] && fnd[1] && fnd[2] && fnd[3])
			return &faces[n1->index];
	}

	return NULL;
}

static MultiresEdge *find_old_edge(ListBase *map, MultiresEdge *edges, int v1, int v2)
{
	IndexNode *n1, *n2;

	for(n1 = map[v1].first; n1; n1 = n1->next) {
		for(n2 = map[v2].first; n2; n2 = n2->next) {
			if(n1->index == n2->index)
				return &edges[n1->index];
		}
	}

	return NULL;
}

static void multires_load_old_edges(ListBase **emap, MultiresLevel *lvl, int *vvmap, int dst, int v1, int v2, int mov)
{
	int emid = find_old_edge(emap[2], lvl->edges, v1, v2)->mid;
	vvmap[dst + mov] = emid;

	if(lvl->next->next) {
		multires_load_old_edges(emap + 1, lvl->next, vvmap, dst + mov, v1, emid, mov / 2);
		multires_load_old_edges(emap + 1, lvl->next, vvmap, dst + mov, v2, emid, -mov / 2);
	}
}

static void multires_load_old_faces(ListBase **fmap, ListBase **emap, MultiresLevel *lvl, int *vvmap, int dst,
					int v1, int v2, int v3, int v4, int st2, int st3)
{
	int fmid;
	int emid13, emid14, emid23, emid24;

	if(lvl && lvl->next) {
		fmid = find_old_face(fmap[1], lvl->faces, v1, v2, v3, v4)->mid;
		vvmap[dst] = fmid;

		emid13 = find_old_edge(emap[1], lvl->edges, v1, v3)->mid;
		emid14 = find_old_edge(emap[1], lvl->edges, v1, v4)->mid;
		emid23 = find_old_edge(emap[1], lvl->edges, v2, v3)->mid;
		emid24 = find_old_edge(emap[1], lvl->edges, v2, v4)->mid;


		multires_load_old_faces(fmap + 1, emap + 1, lvl->next, vvmap, dst + st2 * st3 + st3,
					fmid, v2, emid23, emid24, st2, st3 / 2);

		multires_load_old_faces(fmap + 1, emap + 1, lvl->next, vvmap, dst - st2 * st3 + st3,
					emid14, emid24, fmid, v4, st2, st3 / 2);

		multires_load_old_faces(fmap + 1, emap + 1, lvl->next, vvmap, dst + st2 * st3 - st3,
					emid13, emid23, v3, fmid, st2, st3 / 2);

		multires_load_old_faces(fmap + 1, emap + 1, lvl->next, vvmap, dst - st2 * st3 - st3,
					v1, fmid, emid13, emid14, st2, st3 / 2);

		if(lvl->next->next) {
			multires_load_old_edges(emap, lvl->next, vvmap, dst, emid24, fmid, st3);
			multires_load_old_edges(emap, lvl->next, vvmap, dst, emid13, fmid, -st3);
			multires_load_old_edges(emap, lvl->next, vvmap, dst, emid14, fmid, -st2 * st3);
			multires_load_old_edges(emap, lvl->next, vvmap, dst, emid23, fmid, st2 * st3);
		}
	}
}

static void multires_mvert_to_ss(DerivedMesh *dm, MVert *mvert)
{
	CCGDerivedMesh *ccgdm = (CCGDerivedMesh*) dm;
	CCGSubSurf *ss = ccgdm->ss;
	DMGridData *vd;
	int index;
	int totvert, totedge, totface;
	int gridSize = ccgSubSurf_getGridSize(ss);
	int edgeSize = ccgSubSurf_getEdgeSize(ss);
	int i = 0;

	totface = ccgSubSurf_getNumFaces(ss);
	for(index = 0; index < totface; index++) {
		CCGFace *f = ccgdm->faceMap[index].face;
		int x, y, S, numVerts = ccgSubSurf_getFaceNumVerts(f);

		vd= ccgSubSurf_getFaceCenterData(f);
		copy_v3_v3(vd->co, mvert[i].co);
		i++;
		
		for(S = 0; S < numVerts; S++) {
			for(x = 1; x < gridSize - 1; x++, i++) {
				vd= ccgSubSurf_getFaceGridEdgeData(ss, f, S, x);
				copy_v3_v3(vd->co, mvert[i].co);
			}
		}

		for(S = 0; S < numVerts; S++) {
			for(y = 1; y < gridSize - 1; y++) {
				for(x = 1; x < gridSize - 1; x++, i++) {
					vd= ccgSubSurf_getFaceGridData(ss, f, S, x, y);
					copy_v3_v3(vd->co, mvert[i].co);
				}
			}
		}
	}

	totedge = ccgSubSurf_getNumEdges(ss);
	for(index = 0; index < totedge; index++) {
		CCGEdge *e = ccgdm->edgeMap[index].edge;
		int x;

		for(x = 1; x < edgeSize - 1; x++, i++) {
			vd= ccgSubSurf_getEdgeData(ss, e, x);
			copy_v3_v3(vd->co, mvert[i].co);
		}
	}

	totvert = ccgSubSurf_getNumVerts(ss);
	for(index = 0; index < totvert; index++) {
		CCGVert *v = ccgdm->vertMap[index].vert;

		vd= ccgSubSurf_getVertData(ss, v);
		copy_v3_v3(vd->co, mvert[i].co);
		i++;
	}

	ccgSubSurf_updateToFaces(ss, 0, NULL, 0);
}

/* Loads a multires object stored in the old Multires struct into the new format */
static void multires_load_old_dm(DerivedMesh *dm, Mesh *me, int totlvl)
{
	MultiresLevel *lvl, *lvl1;
	Multires *mr= me->mr;
	MVert *vsrc, *vdst;
	int src, dst;
	int st = multires_side_tot[totlvl - 1] - 1;
	int extedgelen = multires_side_tot[totlvl] - 2;
	int *vvmap; // inorder for dst, map to src
	int crossedgelen;
	int i, j, s, x, totvert, tottri, totquad;

	src = 0;
	dst = 0;
	vsrc = mr->verts;
	vdst = dm->getVertArray(dm);
	totvert = dm->getNumVerts(dm);
	vvmap = MEM_callocN(sizeof(int) * totvert, "multires vvmap");

	lvl1 = mr->levels.first;
	/* Load base verts */
	for(i = 0; i < lvl1->totvert; ++i) {
		vvmap[totvert - lvl1->totvert + i] = src;
		++src;
	}

	/* Original edges */
	dst = totvert - lvl1->totvert - extedgelen * lvl1->totedge;
	for(i = 0; i < lvl1->totedge; ++i) {
		int ldst = dst + extedgelen * i;
		int lsrc = src;
		lvl = lvl1->next;

		for(j = 2; j <= mr->level_count; ++j) {
			int base = multires_side_tot[totlvl - j + 1] - 2;
			int skip = multires_side_tot[totlvl - j + 2] - 1;
			int st = multires_side_tot[j - 1] - 1;

			for(x = 0; x < st; ++x)
				vvmap[ldst + base + x * skip] = lsrc + st * i + x;

			lsrc += lvl->totvert - lvl->prev->totvert;
			lvl = lvl->next;
		}
	}

	/* Center points */
	dst = 0;
	for(i = 0; i < lvl1->totface; ++i) {
		int sides = lvl1->faces[i].v[3] ? 4 : 3;

		vvmap[dst] = src + lvl1->totedge + i;
		dst += 1 + sides * (st - 1) * st;
	}


	/* The rest is only for level 3 and up */
	if(lvl1->next && lvl1->next->next) {
		ListBase **fmap, **emap;
		IndexNode **fmem, **emem;

		/* Face edge cross */
		tottri = totquad = 0;
		crossedgelen = multires_side_tot[totlvl - 1] - 2;
		dst = 0;
		for(i = 0; i < lvl1->totface; ++i) {
			int sides = lvl1->faces[i].v[3] ? 4 : 3;

			lvl = lvl1->next->next;
			++dst;

			for(j = 3; j <= mr->level_count; ++j) {
				int base = multires_side_tot[totlvl - j + 1] - 2;
				int skip = multires_side_tot[totlvl - j + 2] - 1;
				int st = pow(2, j - 2);
				int st2 = pow(2, j - 3);
				int lsrc = lvl->prev->totvert;

				/* Skip exterior edge verts */
				lsrc += lvl1->totedge * st;

				/* Skip earlier face edge crosses */
				lsrc += st2 * (tottri * 3 + totquad * 4);

				for(s = 0; s < sides; ++s) {
					for(x = 0; x < st2; ++x) {
						vvmap[dst + crossedgelen * (s + 1) - base - x * skip - 1] = lsrc;
						++lsrc;
					}
				}

				lvl = lvl->next;
			}

			dst += sides * (st - 1) * st;

			if(sides == 4) ++totquad;
			else ++tottri;

		}

		/* calculate vert to edge/face maps for each level (except the last) */
		fmap = MEM_callocN(sizeof(ListBase*) * (mr->level_count-1), "multires fmap");
		emap = MEM_callocN(sizeof(ListBase*) * (mr->level_count-1), "multires emap");
		fmem = MEM_callocN(sizeof(IndexNode*) * (mr->level_count-1), "multires fmem");
		emem = MEM_callocN(sizeof(IndexNode*) * (mr->level_count-1), "multires emem");
		lvl = lvl1;
		for(i = 0; i < mr->level_count - 1; ++i) {
			create_old_vert_face_map(fmap + i, fmem + i, lvl->faces, lvl->totvert, lvl->totface);
			create_old_vert_edge_map(emap + i, emem + i, lvl->edges, lvl->totvert, lvl->totedge);
			lvl = lvl->next;
		}

		/* Interior face verts */
		lvl = lvl1->next->next;
		dst = 0;
		for(j = 0; j < lvl1->totface; ++j) {
			int sides = lvl1->faces[j].v[3] ? 4 : 3;
			int ldst = dst + 1 + sides * (st - 1);

			for(s = 0; s < sides; ++s) {
				int st2 = multires_side_tot[totlvl - 1] - 2;
				int st3 = multires_side_tot[totlvl - 2] - 2;
				int st4 = st3 == 0 ? 1 : (st3 + 1) / 2;
				int mid = ldst + st2 * st3 + st3;
				int cv = lvl1->faces[j].v[s];
				int nv = lvl1->faces[j].v[s == sides - 1 ? 0 : s + 1];
				int pv = lvl1->faces[j].v[s == 0 ? sides - 1 : s - 1];

				multires_load_old_faces(fmap, emap, lvl1->next, vvmap, mid,
							vvmap[dst], cv,
							find_old_edge(emap[0], lvl1->edges, pv, cv)->mid,
							find_old_edge(emap[0], lvl1->edges, cv, nv)->mid,
							st2, st4);

				ldst += (st - 1) * (st - 1);
			}


			dst = ldst;
		}

		lvl = lvl->next;

		for(i = 0; i < mr->level_count - 1; ++i) {
			MEM_freeN(fmap[i]);
			MEM_freeN(fmem[i]);
			MEM_freeN(emap[i]);
			MEM_freeN(emem[i]);
		}

		MEM_freeN(fmap);
		MEM_freeN(emap);
		MEM_freeN(fmem);
		MEM_freeN(emem);
	}

	/* Transfer verts */
	for(i = 0; i < totvert; ++i)
		copy_v3_v3(vdst[i].co, vsrc[vvmap[i]].co);

	MEM_freeN(vvmap);

	multires_mvert_to_ss(dm, vdst);
}


void multires_load_old(Object *ob, Mesh *me)
{
	MultiresLevel *lvl;
	ModifierData *md;
	MultiresModifierData *mmd;
	DerivedMesh *dm, *orig;
	CustomDataLayer *l;
	int i;

	/* Load original level into the mesh */
	lvl = me->mr->levels.first;
	CustomData_free_layers(&me->vdata, CD_MVERT, lvl->totvert);
	CustomData_free_layers(&me->edata, CD_MEDGE, lvl->totedge);
	CustomData_free_layers(&me->fdata, CD_MFACE, lvl->totface);
	me->totvert = lvl->totvert;
	me->totedge = lvl->totedge;
	me->totface = lvl->totface;
	me->mvert = CustomData_add_layer(&me->vdata, CD_MVERT, CD_CALLOC, NULL, me->totvert);
	me->medge = CustomData_add_layer(&me->edata, CD_MEDGE, CD_CALLOC, NULL, me->totedge);
	me->mface = CustomData_add_layer(&me->fdata, CD_MFACE, CD_CALLOC, NULL, me->totface);
	memcpy(me->mvert, me->mr->verts, sizeof(MVert) * me->totvert);
	for(i = 0; i < me->totedge; ++i) {
		me->medge[i].v1 = lvl->edges[i].v[0];
		me->medge[i].v2 = lvl->edges[i].v[1];
	}
	for(i = 0; i < me->totface; ++i) {
		me->mface[i].v1 = lvl->faces[i].v[0];
		me->mface[i].v2 = lvl->faces[i].v[1];
		me->mface[i].v3 = lvl->faces[i].v[2];
		me->mface[i].v4 = lvl->faces[i].v[3];
	}

	/* Add a multires modifier to the object */
	md = ob->modifiers.first;
	while(md && modifierType_getInfo(md->type)->type == eModifierTypeType_OnlyDeform)
		md = md->next;                          
	mmd = (MultiresModifierData*)modifier_new(eModifierType_Multires);
	BLI_insertlinkbefore(&ob->modifiers, md, mmd);

	for(i = 0; i < me->mr->level_count - 1; ++i)
		multiresModifier_subdivide(mmd, ob, 1, 0);

	mmd->lvl = mmd->totlvl;
	orig = CDDM_from_mesh(me, NULL);
	dm = multires_dm_create_from_derived(mmd, 0, orig, ob, 0, 0);
					   
	multires_load_old_dm(dm, me, mmd->totlvl+1);

	multires_dm_mark_as_modified(dm);
	dm->release(dm);
	orig->release(orig);

	/* Copy the first-level data to the mesh */
	for(i = 0, l = me->mr->vdata.layers; i < me->mr->vdata.totlayer; ++i, ++l)
		CustomData_add_layer(&me->vdata, l->type, CD_REFERENCE, l->data, me->totvert);
	for(i = 0, l = me->mr->fdata.layers; i < me->mr->fdata.totlayer; ++i, ++l)
		CustomData_add_layer(&me->fdata, l->type, CD_REFERENCE, l->data, me->totface);
	memset(&me->mr->vdata, 0, sizeof(CustomData));
	memset(&me->mr->fdata, 0, sizeof(CustomData));

	/* Remove the old multires */
	multires_free(me->mr);
	me->mr= NULL;
}