/*
 * ***** 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) 2001-2002 by NaN Holding BV.
 * All rights reserved.
 *
 * The Original Code is: all of this file.
 *
 * Contributor(s): none yet.
 *
 * ***** END GPL LICENSE BLOCK *****
 */

/** \file blender/editors/object/object_vgroup.c
 *  \ingroup edobj
 */


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

#include "MEM_guardedalloc.h"

#include "DNA_cloth_types.h"
#include "DNA_curve_types.h"
#include "DNA_lattice_types.h"
#include "DNA_meshdata_types.h"
#include "DNA_modifier_types.h"
#include "DNA_object_types.h"
#include "DNA_object_force.h"
#include "DNA_scene_types.h"
#include "DNA_particle_types.h"

#include "BLI_math.h"
#include "BLI_blenlib.h"
#include "BLI_editVert.h"
#include "BLI_utildefines.h"

#include "BKE_context.h"
#include "BKE_customdata.h"
#include "BKE_deform.h"
#include "BKE_depsgraph.h"
#include "BKE_global.h"
#include "BKE_mesh.h"
#include "BKE_report.h"
#include "BKE_DerivedMesh.h"

#include "RNA_access.h"
#include "RNA_define.h"

#include "WM_api.h"
#include "WM_types.h"

#include "ED_object.h"
#include "ED_mesh.h"

#include "UI_resources.h"

#include "object_intern.h"

/************************ Exported Functions **********************/
static void vgroup_remap_update_users(Object *ob, int *map);
static void vgroup_delete_edit_mode(Object *ob, bDeformGroup *defgroup);
static void vgroup_delete_object_mode(Object *ob, bDeformGroup *dg);
static void vgroup_delete_all(Object *ob);

static Lattice *vgroup_edit_lattice(Object *ob)
{
	Lattice *lt= ob->data;
	BLI_assert(ob->type==OB_LATTICE);
	return (lt->editlatt)? lt->editlatt->latt: lt;
}

int ED_vgroup_object_is_edit_mode(Object *ob)
{
	if(ob->type == OB_MESH)
		return (((Mesh*)ob->data)->edit_mesh != NULL);
	else if(ob->type == OB_LATTICE)
		return (((Lattice*)ob->data)->editlatt != NULL);

	return 0;
}

bDeformGroup *ED_vgroup_add_name(Object *ob, const char *name)
{
	bDeformGroup *defgroup;

	if(!ob || !OB_TYPE_SUPPORT_VGROUP(ob->type))
		return NULL;
	
	defgroup = MEM_callocN(sizeof(bDeformGroup), "add deformGroup");

	BLI_strncpy(defgroup->name, name, sizeof(defgroup->name));

	BLI_addtail(&ob->defbase, defgroup);
	defgroup_unique_name(defgroup, ob);

	ob->actdef = BLI_countlist(&ob->defbase);

	return defgroup;
}

bDeformGroup *ED_vgroup_add(Object *ob) 
{
	return ED_vgroup_add_name(ob, "Group");
}

void ED_vgroup_delete(Object *ob, bDeformGroup *defgroup) 
{
	bDeformGroup *dg = (bDeformGroup *)ob->defbase.first;

	while (dg) {
		if (dg == defgroup)
			break;
		dg = dg->next;
	}

	if (dg == NULL)
		return;

	if(ED_vgroup_object_is_edit_mode(ob))
		vgroup_delete_edit_mode(ob, dg);
	else
		vgroup_delete_object_mode(ob, dg);
}

void ED_vgroup_clear(Object *ob)
{
	bDeformGroup *dg= (bDeformGroup *)ob->defbase.first;
	int edit_mode= ED_vgroup_object_is_edit_mode(ob);

	while (dg) {
		bDeformGroup *next_dg= dg->next;

		if(edit_mode)
			vgroup_delete_edit_mode(ob, dg);
		else
			vgroup_delete_object_mode(ob, dg);

		dg= next_dg;
	}
}

int ED_vgroup_data_create(ID *id)
{
	/* create deform verts */

	if(GS(id->name)==ID_ME) {
		Mesh *me= (Mesh *)id;
		me->dvert= CustomData_add_layer(&me->vdata, CD_MDEFORMVERT, CD_CALLOC, NULL, me->totvert);
		return TRUE;
	}
	else if(GS(id->name)==ID_LT) {
		Lattice *lt= (Lattice *)id;
		lt->dvert= MEM_callocN(sizeof(MDeformVert)*lt->pntsu*lt->pntsv*lt->pntsw, "lattice deformVert");
		return TRUE;
	}
	else {
		return FALSE;
	}
}

static int ED_vgroup_give_parray(ID *id, MDeformVert ***dvert_arr, int *dvert_tot, const short use_vert_sel)
{
	*dvert_tot = 0;
	*dvert_arr = NULL;

	if(id) {
		switch(GS(id->name)) {
			case ID_ME:
			{
				Mesh *me = (Mesh *)id;

				if(me->edit_mesh) {
					EditMesh *em = me->edit_mesh;
					EditVert *eve;
					int i;

					if (!CustomData_has_layer(&em->vdata, CD_MDEFORMVERT)) {
						return 0;
					}

					i= BLI_countlist(&em->verts);

					*dvert_arr= MEM_mallocN(sizeof(void*)*i, "vgroup parray from me");
					*dvert_tot = i;

					i = 0;

					if (use_vert_sel) {
						for (eve=em->verts.first; eve; eve=eve->next, i++) {
							(*dvert_arr)[i] = (eve->f & SELECT) ?
											   CustomData_em_get(&em->vdata, eve->data, CD_MDEFORMVERT) : NULL;
						}
					}
					else {
						for (eve=em->verts.first; eve; eve=eve->next, i++) {
							(*dvert_arr)[i] = CustomData_em_get(&em->vdata, eve->data, CD_MDEFORMVERT);
						}
					}

					return 1;
				}
				else if(me->dvert) {
					MVert *mvert= me->mvert;
					MDeformVert *dvert= me->dvert;
					int i;

					*dvert_tot= me->totvert;
					*dvert_arr= MEM_mallocN(sizeof(void*)*me->totvert, "vgroup parray from me");

					if (use_vert_sel) {
						for (i=0; i<me->totvert; i++) {
							(*dvert_arr)[i] = (mvert[i].flag & SELECT) ?
							                   &dvert[i] : NULL;
						}
					}
					else {
						for (i=0; i<me->totvert; i++) {
							(*dvert_arr)[i] = me->dvert + i;
						}
					}

					return 1;
				}
				else {
					return 0;
				}
			}
			case ID_LT:
			{
				int i=0;

				Lattice *lt= (Lattice *)id;
				lt= (lt->editlatt)? lt->editlatt->latt: lt;

				if(lt->dvert) {
					BPoint *def= lt->def;
					*dvert_tot= lt->pntsu*lt->pntsv*lt->pntsw;
					*dvert_arr= MEM_mallocN(sizeof(void*)*(*dvert_tot), "vgroup parray from me");

					if (use_vert_sel) {
						for (i=0; i<*dvert_tot; i++) {
							(*dvert_arr)[i] = (def->f1 & SELECT) ?
							                   &lt->dvert[i] : NULL;
						}
					}
					else {
						for (i=0; i<*dvert_tot; i++) {
							(*dvert_arr)[i] = lt->dvert + i;
						}
					}

					return 1;
				}
				else {
					return 0;
				}
			}
		}
	}

	return 0;
}

/* returns true if the id type supports weights */
int ED_vgroup_give_array(ID *id, MDeformVert **dvert_arr, int *dvert_tot)
{
	if(id) {
		switch(GS(id->name)) {
			case ID_ME:
			{
				Mesh *me = (Mesh *)id;
				*dvert_arr= me->dvert;
				*dvert_tot= me->totvert;
				return TRUE;
			}
			case ID_LT:
			{
				Lattice *lt= (Lattice *)id;
				lt= (lt->editlatt)? lt->editlatt->latt: lt;
				*dvert_arr= lt->dvert;
				*dvert_tot= lt->pntsu*lt->pntsv*lt->pntsw;
				return TRUE;
			}
		}
	}

	*dvert_arr= NULL;
	*dvert_tot= 0;
	return FALSE;
}

/* matching index only */
int ED_vgroup_copy_array(Object *ob, Object *ob_from)
{
	MDeformVert **dvert_array_from, **dvf;
	MDeformVert **dvert_array, **dv;
	int dvert_tot_from;
	int dvert_tot;
	int i;
	int defbase_tot_from= BLI_countlist(&ob_from->defbase);
	int defbase_tot= BLI_countlist(&ob->defbase);
	short new_vgroup= FALSE;

	ED_vgroup_give_parray(ob_from->data, &dvert_array_from, &dvert_tot_from, FALSE);
	ED_vgroup_give_parray(ob->data, &dvert_array, &dvert_tot, FALSE);

	if((dvert_array == NULL) && (dvert_array_from != NULL) && ED_vgroup_data_create(ob->data)) {
		ED_vgroup_give_parray(ob->data, &dvert_array, &dvert_tot, FALSE);
		new_vgroup= TRUE;
	}

	if(ob==ob_from || dvert_tot==0 || (dvert_tot != dvert_tot_from) || dvert_array_from==NULL || dvert_array==NULL) {
		if (dvert_array) MEM_freeN(dvert_array);
		if (dvert_array_from) MEM_freeN(dvert_array_from);

		if(new_vgroup == TRUE) {
			/* free the newly added vgroup since it wasn't compatible */
			vgroup_delete_all(ob);
		}
		return 0;
	}

	/* do the copy */
	BLI_freelistN(&ob->defbase);
	BLI_duplicatelist(&ob->defbase, &ob_from->defbase);
	ob->actdef= ob_from->actdef;

	if(defbase_tot_from < defbase_tot) {
		/* correct vgroup indices because the number of vgroups is being reduced. */
		int *remap= MEM_mallocN(sizeof(int) * (defbase_tot + 1), __func__);
		for(i=0; i<=defbase_tot_from; i++) remap[i]= i;
		for(; i<=defbase_tot; i++) remap[i]= 0; /* can't use these, so disable */

		vgroup_remap_update_users(ob, remap);
		MEM_freeN(remap);
	}

	dvf= dvert_array_from;
	dv= dvert_array;

	for(i=0; i<dvert_tot; i++, dvf++, dv++) {
		if((*dv)->dw)
			MEM_freeN((*dv)->dw);

		*(*dv)= *(*dvf);

		if((*dv)->dw)
			(*dv)->dw= MEM_dupallocN((*dv)->dw);
	}

	MEM_freeN(dvert_array);
	MEM_freeN(dvert_array_from);

	return 1;
}


/* for Mesh in Object mode */
/* allows editmode for Lattice */
static void ED_vgroup_nr_vert_add(Object *ob,
                                  const int def_nr, const int vertnum,
                                  const float weight, const int assignmode)
{
	/* add the vert to the deform group with the
	 * specified number
	 */
	MDeformVert *dvert= NULL;
	int	tot;

	/* get the vert */
	ED_vgroup_give_array(ob->data, &dvert, &tot);
	
	if(dvert==NULL)
		return;

	/* check that vertnum is valid before trying to get the relevant dvert */
	if ((vertnum < 0) || (vertnum >= tot))
		return;


	if (dvert) {
		MDeformVert *dv= &dvert[vertnum];
		MDeformWeight *dw;

		/* Lets first check to see if this vert is
		 * already in the weight group -- if so
		 * lets update it
		 */

		dw= defvert_find_index(dv, def_nr);

		if (dw) {
			switch(assignmode) {
			case WEIGHT_REPLACE:
				dw->weight = weight;
				break;
			case WEIGHT_ADD:
				dw->weight += weight;
				if(dw->weight >= 1.0f)
					dw->weight = 1.0f;
				break;
			case WEIGHT_SUBTRACT:
				dw->weight -= weight;
				/* if the weight is zero or less then
				 * remove the vert from the deform group
				 */
				if(dw->weight <= 0.0f) {
					defvert_remove_group(dv, dw);
				}
				break;
			}
		}
		else {
			/* if the vert wasn't in the deform group then
			 * we must take a different form of action ...
			 */

			switch(assignmode) {
			case WEIGHT_SUBTRACT:
				/* if we are subtracting then we don't
				 * need to do anything
				 */
				return;

			case WEIGHT_REPLACE:
			case WEIGHT_ADD:
				/* if we are doing an additive assignment, then
				 * we need to create the deform weight
				 */

				/* we checked if the vertex was added before so no need to test again, simply add */
				defvert_add_index_notest(dv, def_nr, weight);
			}
		}
	}
}

/* called while not in editmode */
void ED_vgroup_vert_add(Object *ob, bDeformGroup *dg, int vertnum, float weight, int assignmode)
{
	/* add the vert to the deform group with the
	 * specified assign mode
	 */
	const int def_nr= BLI_findindex(&ob->defbase, dg);

	MDeformVert *dv= NULL;
	int tot;

	/* get the deform group number, exit if
	 * it can't be found
	 */
	if(def_nr < 0) return;

	/* if there's no deform verts then create some,
	 */
	if(ED_vgroup_give_array(ob->data, &dv, &tot) && dv==NULL)
		ED_vgroup_data_create(ob->data);

	/* call another function to do the work
	 */
	ED_vgroup_nr_vert_add(ob, def_nr, vertnum, weight, assignmode);
}

/* mesh object mode, lattice can be in editmode */
void ED_vgroup_vert_remove(Object *ob, bDeformGroup	*dg, int vertnum)
{
	/* This routine removes the vertex from the specified
	 * deform group.
	 */

	/* TODO, this is slow in a loop, better pass def_nr directly, but leave for later... - campbell */
	const int def_nr= BLI_findindex(&ob->defbase, dg);

	if(def_nr != -1) {
		MDeformVert *dvert= NULL;
		int tot;

		/* get the deform vertices corresponding to the
		 * vertnum
		 */
		ED_vgroup_give_array(ob->data, &dvert, &tot);

		if(dvert) {
			MDeformVert *dv= &dvert[vertnum];
			MDeformWeight *dw;

			dw= defvert_find_index(dv, def_nr);
			defvert_remove_group(dv, dw); /* dw can be NULL */
		}
	}
}

static float get_vert_def_nr(Object *ob, const int def_nr, const int vertnum)
{
	MDeformVert *dv= NULL;
	EditVert *eve;
	Mesh *me;

	/* get the deform vertices corresponding to the vertnum */
	if(ob->type==OB_MESH) {
		me= ob->data;

		if(me->edit_mesh) {
			eve= BLI_findlink(&me->edit_mesh->verts, vertnum);
			if(!eve) {
				return 0.0f;
			}
			dv= CustomData_em_get(&me->edit_mesh->vdata, eve->data, CD_MDEFORMVERT);
		}
		else {
			if(vertnum >= me->totvert) {
				return 0.0f;
			}
			dv = &me->dvert[vertnum];
		}
	}
	else if(ob->type==OB_LATTICE) {
		Lattice *lt= vgroup_edit_lattice(ob);

		if(lt->dvert) {
			if(vertnum >= lt->pntsu*lt->pntsv*lt->pntsw) {
				return 0.0f;
			}
			dv = &lt->dvert[vertnum];
		}
	}
	
	if (dv) {
		MDeformWeight *dw= defvert_find_index(dv, def_nr);
		if (dw) {
			return dw->weight;
		}
	}

	return -1;
}

float ED_vgroup_vert_weight(Object *ob, bDeformGroup *dg, int vertnum)
{
	const int def_nr= BLI_findindex(&ob->defbase, dg);

	if(def_nr == -1) {
		return -1;
	}

	return get_vert_def_nr(ob, def_nr, vertnum);
}

void ED_vgroup_select_by_name(Object *ob, const char *name)
{	/* note: ob->actdef==0 signals on painting to create a new one, if a bone in posemode is selected */
	ob->actdef= defgroup_name_index(ob, name) + 1;
}

/********************** Operator Implementations *********************/

/* only in editmode */
static void vgroup_select_verts(Object *ob, int select)
{
	const int def_nr= ob->actdef-1;
	MDeformVert *dv;

	if (!BLI_findlink(&ob->defbase, def_nr)) {
		return;
	}

	if(ob->type == OB_MESH) {
		Mesh *me= ob->data;

		if (me->edit_mesh) {
			EditMesh *em = BKE_mesh_get_editmesh(me);
			EditVert *eve;

			for (eve=em->verts.first; eve; eve=eve->next) {
				if (!eve->h) {
					dv= CustomData_em_get(&em->vdata, eve->data, CD_MDEFORMVERT);
					if (defvert_find_index(dv, def_nr)) {
						if (select)  eve->f |=  SELECT;
						else         eve->f &= ~SELECT;
					}
				}
			}
			/* this has to be called, because this function operates on vertices only */
			if(select) EM_select_flush(em);	// vertices to edges/faces
			else EM_deselect_flush(em);

			BKE_mesh_end_editmesh(me, em);
		}
		else {
			if (me->dvert) {
				MVert *mv;
				MDeformVert *dv;
				int i;

				mv = me->mvert;
				dv = me->dvert;

				for (i=0; i<me->totvert; i++, mv++, dv++) {
					if (!(mv->flag & ME_HIDE)) {
						if (defvert_find_index(dv, def_nr)) {
							if (select)  mv->flag |=  SELECT;
							else         mv->flag &= ~SELECT;
						}
					}
				}

				paintvert_flush_flags(ob);
			}
		}
	}
	else if(ob->type == OB_LATTICE) {
		Lattice *lt= vgroup_edit_lattice(ob);
		
		if(lt->dvert) {
			BPoint *bp;
			int a, tot;
			
			dv= lt->dvert;

			tot= lt->pntsu*lt->pntsv*lt->pntsw;
			for(a=0, bp= lt->def; a<tot; a++, bp++, dv++) {
				if (defvert_find_index(dv, def_nr)) {
					if (select)  bp->f1 |=  SELECT;
					else         bp->f1 &= ~SELECT;
				}
			}
		}
	}
}

static void vgroup_duplicate(Object *ob)
{
	bDeformGroup *dg, *cdg;
	char name[sizeof(dg->name)];
	MDeformWeight *dw_org, *dw_cpy;
	MDeformVert **dvert_array=NULL;
	int i, idg, icdg, dvert_tot=0;

	dg = BLI_findlink(&ob->defbase, (ob->actdef-1));
	if(!dg)
		return;
	
	if(!strstr(dg->name, "_copy")) {
		BLI_snprintf(name, sizeof(name), "%s_copy", dg->name);
	}
	else {
		BLI_snprintf(name, sizeof(name), "%s", dg->name);
	}

	cdg = defgroup_duplicate(dg);
	BLI_strncpy(cdg->name, name, sizeof(cdg->name));
	defgroup_unique_name(cdg, ob);

	BLI_addtail(&ob->defbase, cdg);

	idg = (ob->actdef-1);
	ob->actdef = BLI_countlist(&ob->defbase);
	icdg = (ob->actdef-1);

	/* TODO, we might want to allow only copy selected verts here? - campbell */
	ED_vgroup_give_parray(ob->data, &dvert_array, &dvert_tot, FALSE);

	if (dvert_array) {
		for(i = 0; i < dvert_tot; i++) {
			MDeformVert *dv= dvert_array[i];
			dw_org = defvert_find_index(dv, idg);
			if(dw_org) {
				/* defvert_verify_index re-allocs org so need to store the weight first */
				dw_cpy = defvert_verify_index(dv, icdg);
				dw_cpy->weight = dw_org->weight;
			}
		}

		MEM_freeN(dvert_array);
	}
}

static void vgroup_normalize(Object *ob)
{
	MDeformWeight *dw;
	MDeformVert *dv, **dvert_array=NULL;
	int i, dvert_tot=0;
	const int def_nr= ob->actdef-1;

	Mesh *me = ob->data;
	const int use_vert_sel= (me->editflag & ME_EDIT_VERT_SEL) != 0;

	if (!BLI_findlink(&ob->defbase, def_nr)) {
		return;
	}

	ED_vgroup_give_parray(ob->data, &dvert_array, &dvert_tot, use_vert_sel);

	if (dvert_array) {
		float weight_max = 0.0f;

		for(i = 0; i < dvert_tot; i++) {

			/* incase its not selected */
			if (!(dv = dvert_array[i])) {
				continue;
			}

			dw = defvert_find_index(dv, def_nr);
			if(dw) {
				weight_max = MAX2(dw->weight, weight_max);
			}
		}

		if(weight_max > 0.0f) {
			for(i = 0; i < dvert_tot; i++) {
				
				/* incase its not selected */
				if (!(dv = dvert_array[i])) {
					continue;
				}

				dw = defvert_find_index(dv, def_nr);
				if(dw) {
					dw->weight /= weight_max;
					
					/* incase of division errors with very low weights */
					CLAMP(dw->weight, 0.0f, 1.0f);
				}
			}
		}

		MEM_freeN(dvert_array);
	}
}

/* This adds the indices of vertices to a list if they are not already present
It returns the number that it added (0-2)
It relies on verts having -1 for unassigned indices
*/
static int tryToAddVerts(int *verts, int length, int a, int b)
{
	char containsA = FALSE;
	char containsB = FALSE;
	int added = 0;
	int i;
	for(i = 0; i < length && (!containsA || !containsB); i++) {
		if(verts[i] == a) {
			containsA = TRUE;
		} else if(verts[i] == b) {
			containsB = TRUE;
		} else if(verts[i] == -1) {
			if(!containsA) {
				verts[i] = a;
				containsA = TRUE;
				added++;
			} else if(!containsB){
				verts[i] = b;
				containsB = TRUE;
				added++;
			}
		}
	}
	return added;
}

/* This finds all of the vertices connected to vert by an edge
and returns an array of indices of size count

count is an int passed by reference so it can be assigned the value of the length here.
*/
static int* getSurroundingVerts(Mesh *me, int vert, int *count)
{
	int length = 0;
	int *tverts;
	int *verts = NULL;
	MFace *mf = me->mface;
	int totface = me->totface;
	int found = 0;
	int i;
	for(i = 0; i < totface; i++, mf++) {
		if(vert == mf->v1 || vert == mf->v2 || vert == mf->v3 || (mf->v4 &&vert == mf->v4)) {
			length+=2;
		}
	}
	if(!length) {
		return NULL;
	}
	tverts = MEM_mallocN(sizeof(int)*length, "tempSurroundingVerts");
	mf = me->mface;
	for(i = 0; i < length; i++) {
		tverts[i] = -1;
	}
	for(i = 0; i < totface; i++, mf++) {
		int a=-1, b=-1;
		if(mf->v1 == vert) {
			a = mf->v2;
			if(mf->v4) {
				b = mf->v4;
			} else {
				b = mf->v3;
			}
		} else if(mf->v2 == vert) {
			a = mf->v1;
			b = mf->v3;
		} else if(mf->v3 == vert) {
			a = mf->v2;
			if(mf->v4) {
				b = mf->v4;
			} else {
				b = mf->v1;
			}
		} else if (mf->v4 && mf->v4 == vert){
			a = mf->v1;
			b = mf->v3;
		} else {
			continue;
		}
		found += tryToAddVerts(tverts, length, a, b);
	}
	if(found) {
		verts = MEM_mallocN(sizeof(int)* found, "surroundingVerts");
		for(i = 0; i < found; i++) {
			verts[i] = tverts[i];
		}
		*count = found;
	}
	MEM_freeN(tverts);
	return verts;
}

/* get a single point in space by averaging a point cloud (vectors of size 3)
coord is the place the average is stored, points is the point cloud, count is the number of points in the cloud
*/
static void getSingleCoordinate(MVert *points, int count, float coord[3])
{
	int i;
	zero_v3(coord);
	for(i = 0; i < count; i++) {
		add_v3_v3(coord, points[i].co);
	}
	mul_v3_fl(coord, 1.0f/count);
}

/* given a plane and a start and end position,
compute the amount of vertical distance relative to the plane and store it in dists,
then get the horizontal and vertical change and store them in changes
*/
static void getVerticalAndHorizontalChange(const float norm[3], float d, const float coord[3],
                                           const float start[3], float distToStart,
                                           float *end, float (*changes)[2], float *dists, int index)
{
	// A=Q-((Q-P).N)N
	// D = (a*x0 + b*y0 +c*z0 +d)
	float projA[3], projB[3];

	closest_to_plane_v3(projA, coord, norm, start);
	closest_to_plane_v3(projB, coord, norm, end);
	// (vertical and horizontal refer to the plane's y and xz respectively)
	// vertical distance
	dists[index] = norm[0]*end[0] + norm[1]*end[1] + norm[2]*end[2] + d;
	// vertical change
	changes[index][0] = dists[index] - distToStart;
	//printf("vc %f %f\n", distance(end, projB, 3)-distance(start, projA, 3), changes[index][0]);
	// horizontal change
	changes[index][1] = len_v3v3(projA, projB);
}

// I need the derived mesh to be forgotten so the positions are recalculated with weight changes (see dm_deform_recalc)
static void dm_deform_clear(DerivedMesh *dm, Object *ob)
{
	if(ob->derivedDeform && (ob->derivedDeform)==dm) {
		ob->derivedDeform->needsFree = 1;
		ob->derivedDeform->release(ob->derivedDeform);
		ob->derivedDeform = NULL;
	}
	else if(dm) {
		dm->needsFree = 1;
		dm->release(dm);
	}
}

// recalculate the deformation
static DerivedMesh* dm_deform_recalc(Scene *scene, Object *ob)
{
	return mesh_get_derived_deform(scene, ob, CD_MASK_BAREMESH);
}

/* by changing nonzero weights, try to move a vertex in me->mverts with index 'index' to
distToBe distance away from the provided plane strength can change distToBe so that it moves
towards distToBe by that percentage cp changes how much the weights are adjusted
to check the distance

index is the index of the vertex being moved
norm and d are the plane's properties for the equation: ax + by + cz + d = 0
coord is a point on the plane
*/
static void moveCloserToDistanceFromPlane(Scene *scene, Object *ob, Mesh *me, int index, float norm[3],
                                          float coord[3], float d, float distToBe, float strength, float cp)
{
	DerivedMesh *dm;
	MDeformWeight *dw;
	MVert m;
	MDeformVert *dvert = me->dvert+index;
	int totweight = dvert->totweight;
	float oldw = 0;
	float oldPos[3] = {0};
	float vc, hc, dist = 0.0f;
	int i, k;
	float (*changes)[2] = MEM_mallocN(sizeof(float *)*totweight*2, "vertHorzChange");
	float *dists = MEM_mallocN(sizeof(float)*totweight, "distance");

	/* track if up or down moved it closer for each bone */
	int *upDown = MEM_callocN(sizeof(int)*totweight, "upDownTracker");

	int *dwIndices = MEM_callocN(sizeof(int)*totweight, "dwIndexTracker");
	float distToStart;
	int bestIndex = 0;
	char wasChange;
	char wasUp;
	int lastIndex = -1;
	float originalDistToBe = distToBe;
	do {
		wasChange = FALSE;
		dm = dm_deform_recalc(scene, ob);
		dm->getVert(dm, index, &m);
		copy_v3_v3(oldPos, m.co);
		distToStart = dot_v3v3(norm, oldPos) + d;

		if(distToBe == originalDistToBe) {
			distToBe += distToStart - distToStart*strength;
		}
		for(i = 0; i < totweight; i++) {
			dwIndices[i] = i;
			dw = (dvert->dw+i);
			vc = hc = 0;
			if(!dw->weight) {
				changes[i][0] = 0;
				changes[i][1] = 0;
				dists[i] = distToStart;
				continue;
			}
			for(k = 0; k < 2; k++) {
				if(dm) {
					dm_deform_clear(dm, ob); dm = NULL;
				}
				oldw = dw->weight;
				if(k) {
					dw->weight *= 1+cp;
				} else {
					dw->weight /= 1+cp;
				}
				if(dw->weight == oldw) {
					changes[i][0] = 0;
					changes[i][1] = 0;
					dists[i] = distToStart;
					break;
				}
				if(dw->weight > 1) {
					dw->weight = 1;
				}
				dm = dm_deform_recalc(scene, ob);
				dm->getVert(dm, index, &m);
				getVerticalAndHorizontalChange(norm, d, coord, oldPos, distToStart, m.co, changes, dists, i);
				dw->weight = oldw;
				if(!k) {
					vc = changes[i][0];
					hc = changes[i][1];
					dist = dists[i];
				} else {
					if(fabs(dist - distToBe) < fabs(dists[i] - distToBe)) {
						upDown[i] = 0;
						changes[i][0] = vc;
						changes[i][1] = hc;
						dists[i] = dist;
					} else {
						upDown[i] = 1;
					}
					if(fabs(dists[i] - distToBe) > fabs(distToStart - distToBe)) {
						changes[i][0] = 0;
						changes[i][1] = 0;
						dists[i] = distToStart;
					}
				}
			}
		}
		// sort the changes by the vertical change
		for(k = 0; k < totweight; k++) {
			float tf;
			int ti;
			bestIndex = k;
			for(i = k+1; i < totweight; i++) {
				dist = dists[i];

				if(fabs(dist) > fabs(dists[i])) {
					bestIndex = i;
				}
			}
			// switch with k
			if(bestIndex != k) {
				ti = upDown[k];
				upDown[k] = upDown[bestIndex];
				upDown[bestIndex] = ti;

				ti = dwIndices[k];
				dwIndices[k] = dwIndices[bestIndex];
				dwIndices[bestIndex] = ti;

				tf = changes[k][0];
				changes[k][0] = changes[bestIndex][0];
				changes[bestIndex][0] = tf;

				tf = changes[k][1];
				changes[k][1] = changes[bestIndex][1];
				changes[bestIndex][1] = tf;

				tf = dists[k];
				dists[k] = dists[bestIndex];
				dists[bestIndex] = tf;
			}
		}
		bestIndex = -1;
		// find the best change with an acceptable horizontal change
		for(i = 0; i < totweight; i++) {
			if(fabs(changes[i][0]) > fabs(changes[i][1]*2.0f)) {
				bestIndex = i;
				break;
			}
		}
		if(bestIndex != -1) {
			wasChange = TRUE;
			// it is a good place to stop if it tries to move the opposite direction
			// (relative to the plane) of last time
			if(lastIndex != -1) {
				if(wasUp != upDown[bestIndex]) {
					wasChange = FALSE;
				}
			}
			lastIndex = bestIndex;
			wasUp = upDown[bestIndex];
			dw = (dvert->dw+dwIndices[bestIndex]);
			oldw = dw->weight;
			if(upDown[bestIndex]) {
				dw->weight *= 1+cp;
			} else {
				dw->weight /= 1+cp;
			}
			if(dw->weight > 1) {
				dw->weight = 1;
			}
			if(oldw == dw->weight) {
				wasChange = FALSE;
			}
			if(dm) {
				dm_deform_clear(dm, ob); dm = NULL;
			}
		}
	} while(wasChange && (distToStart-distToBe)/fabsf(distToStart-distToBe) ==
	                     (dists[bestIndex]-distToBe)/fabsf(dists[bestIndex]-distToBe));
	MEM_freeN(upDown);
	MEM_freeN(changes);
	MEM_freeN(dists);
	MEM_freeN(dwIndices);
}

/* this is used to try to smooth a surface by only adjusting the nonzero weights of a vertex 
but it could be used to raise or lower an existing 'bump.' */
static void vgroup_fix(Scene *scene, Object *ob, float distToBe, float strength, float cp)
{
	int i;

	Mesh *me = ob->data;
	MVert *mvert = me->mvert;
	const int use_vert_sel= (me->editflag & ME_EDIT_VERT_SEL) != 0;
	int *verts = NULL;
	for(i = 0; i < me->totvert && mvert; i++, mvert++) {
		
		if(use_vert_sel && (mvert->flag & SELECT)) {
			
			int count=0;
			if((verts = getSurroundingVerts(me, i, &count))) {
				MVert m;
				MVert *p = MEM_callocN(sizeof(MVert)*(count), "deformedPoints");
				int k;

				DerivedMesh *dm = mesh_get_derived_deform(scene, ob, CD_MASK_BAREMESH);
				for(k = 0; k < count; k++) {
					dm->getVert(dm, verts[k], &m);
					p[k] = m;
				}
				
				if(count >= 3) {
					float d /*, dist */ /* UNUSED */, mag;
					float coord[3];
					float norm[3];
					getSingleCoordinate(p, count, coord);
					dm->getVert(dm, i, &m);
					sub_v3_v3v3(norm, m.co, coord);
					mag= normalize_v3(norm);
					if(mag) { /* zeros fix */
						d = -dot_v3v3(norm, coord);
						/* dist = (norm[0]*m.co[0] + norm[1]*m.co[1] + norm[2]*m.co[2] + d); */ /* UNUSED */
						moveCloserToDistanceFromPlane(scene, ob, me, i, norm, coord, d, distToBe, strength, cp);
					}
				}

				MEM_freeN(verts);
				MEM_freeN(p);
			}
		}
	}
}

static void vgroup_levels(Object *ob, float offset, float gain)
{
	MDeformWeight *dw;
	MDeformVert *dv, **dvert_array=NULL;
	int i, dvert_tot=0;
	const int def_nr= ob->actdef-1;

	Mesh *me = ob->data;
	const int use_vert_sel= (me->editflag & ME_EDIT_VERT_SEL) != 0;

	if (!BLI_findlink(&ob->defbase, def_nr)) {
		return;
	}

	ED_vgroup_give_parray(ob->data, &dvert_array, &dvert_tot, use_vert_sel);

	if (dvert_array) {
		for(i = 0; i < dvert_tot; i++) {

			/* incase its not selected */
			if (!(dv = dvert_array[i])) {
				continue;
			}

			dw = defvert_find_index(dv, def_nr);
			if(dw) {
				dw->weight = gain * (dw->weight + offset);

				CLAMP(dw->weight, 0.0f, 1.0f);
			}
		}

		MEM_freeN(dvert_array);
	}
}

/* TODO - select between groups */
static void vgroup_normalize_all(Object *ob, int lock_active)
{
	MDeformVert *dv, **dvert_array=NULL;
	int i, dvert_tot=0;
	const int def_nr= ob->actdef-1;

	Mesh *me = ob->data;
	const int use_vert_sel= (me->editflag & ME_EDIT_VERT_SEL) != 0;

	if (lock_active && !BLI_findlink(&ob->defbase, def_nr)) {
		return;
	}

	ED_vgroup_give_parray(ob->data, &dvert_array, &dvert_tot, use_vert_sel);

	if (dvert_array) {
		if(lock_active) {

			for(i = 0; i < dvert_tot; i++) {
				/* incase its not selected */
				if (!(dv = dvert_array[i])) {
					continue;
				}

				defvert_normalize_lock(dv, def_nr);
			}
		}
		else {
			for(i = 0; i < dvert_tot; i++) {

				/* incase its not selected */
				if (!(dv = dvert_array[i])) {
					continue;
				}

				defvert_normalize(dv);
			}
		}

		MEM_freeN(dvert_array);
	}
}


static void vgroup_lock_all(Object *ob, int action)
{
	bDeformGroup *dg;

	if(action == SEL_TOGGLE) {
		action= SEL_SELECT;
		for(dg= ob->defbase.first; dg; dg= dg->next) {
			if(dg->flag & DG_LOCK_WEIGHT) {
				action= SEL_DESELECT;
				break;
			}
		}
	}

	for(dg= ob->defbase.first; dg; dg= dg->next) {
		switch(action) {
			case SEL_SELECT:
				dg->flag |= DG_LOCK_WEIGHT;
				break;
			case SEL_DESELECT:
				dg->flag &= ~DG_LOCK_WEIGHT;
				break;
			case SEL_INVERT:
				dg->flag ^= DG_LOCK_WEIGHT;
				break;
		}
	}
}

static void vgroup_invert(Object *ob, const short auto_assign, const short auto_remove)
{
	MDeformWeight *dw;
	MDeformVert *dv, **dvert_array=NULL;
	int i, dvert_tot=0;
	const int def_nr= ob->actdef-1;
	
	Mesh *me = ob->data;
	const int use_vert_sel= (me->editflag & ME_EDIT_VERT_SEL) != 0;

	if (!BLI_findlink(&ob->defbase, def_nr)) {
		return;
	}

	ED_vgroup_give_parray(ob->data, &dvert_array, &dvert_tot, use_vert_sel);

	if (dvert_array) {
		for(i = 0; i < dvert_tot; i++) {

			/* incase its not selected */
			if (!(dv = dvert_array[i])) {
				continue;
			}

			if (auto_assign) {
				dw= defvert_verify_index(dv, def_nr);
			}
			else {
				dw= defvert_find_index(dv, def_nr);
			}

			if(dw) {
				dw->weight = 1.0f - dw->weight;

				if(auto_remove && dw->weight <= 0.0f) {
					defvert_remove_group(dv, dw);
				}
			}
		}

		MEM_freeN(dvert_array);
	}
}

static void vgroup_blend(Object *ob)
{
	MDeformWeight *dw;
	MDeformVert *dvert_array=NULL, *dvert;
	int i, dvert_tot=0;
	const int def_nr= ob->actdef-1;

	EditMesh *em= BKE_mesh_get_editmesh(((Mesh *)ob->data));
	// ED_vgroup_give_array(ob->data, &dvert_array, &dvert_tot);

	if (em==NULL)
		return;

	if (BLI_findlink(&ob->defbase, def_nr)) {
		int sel1, sel2;
		int i1, i2;

		EditEdge *eed;
		EditVert *eve;
		float *vg_weights;
		float *vg_users;

		i= 0;
		for(eve= em->verts.first; eve; eve= eve->next)
			eve->tmp.l= i++;

		dvert_tot= i;

		vg_weights= MEM_callocN(sizeof(float)*dvert_tot, "vgroup_blend_f");
		vg_users= MEM_callocN(sizeof(int)*dvert_tot, "vgroup_blend_i");

		for(eed= em->edges.first; eed; eed= eed->next) {
			sel1= eed->v1->f & SELECT;
			sel2= eed->v2->f & SELECT;

			if(sel1 != sel2) {
				/* i1 is always the selected one */
				if(sel1==TRUE && sel2==FALSE) {
					i1= eed->v1->tmp.l;
					i2= eed->v2->tmp.l;
					eve= eed->v2;
				}
				else {
					i2= eed->v1->tmp.l;
					i1= eed->v2->tmp.l;
					eve= eed->v1;
				}

				vg_users[i1]++;

				/* TODO, we may want object mode blending */
				if(em)	dvert= CustomData_em_get(&em->vdata, eve->data, CD_MDEFORMVERT);
				else	dvert= dvert_array+i2;

				dw= defvert_find_index(dvert, def_nr);

				if(dw) {
					vg_weights[i1] += dw->weight;
				}
			}
		}

		i= 0;
		for(eve= em->verts.first; eve; eve= eve->next) {
			if(eve->f & SELECT && vg_users[i] > 0) {
				/* TODO, we may want object mode blending */
				if(em)	dvert= CustomData_em_get(&em->vdata, eve->data, CD_MDEFORMVERT);
				else	dvert= dvert_array+i;

				dw= defvert_verify_index(dvert, def_nr);
				dw->weight= vg_weights[i] / (float)vg_users[i];

				/* incase of division errors */
				CLAMP(dw->weight, 0.0f, 1.0f);
			}

			i++;
		}
		MEM_freeN(vg_weights);
		MEM_freeN(vg_users);
	}
}

static void vgroup_clean(Object *ob, const float epsilon, int keep_single)
{
	MDeformWeight *dw;
	MDeformVert *dv, **dvert_array=NULL;
	int i, dvert_tot=0;
	const int def_nr= ob->actdef-1;
	
	Mesh *me = ob->data;
	const int use_vert_sel= (me->editflag & ME_EDIT_VERT_SEL) != 0;

	if (!BLI_findlink(&ob->defbase, def_nr)) {
		return;
	}

	ED_vgroup_give_parray(ob->data, &dvert_array, &dvert_tot, use_vert_sel);

	if (dvert_array) {
		/* only the active group */
		for(i = 0; i < dvert_tot; i++) {

			/* incase its not selected */
			if (!(dv = dvert_array[i])) {
				continue;
			}

			dw= defvert_find_index(dv, def_nr);

			if (dw) {
				if (dw->weight <= epsilon) {
					if(keep_single==FALSE || dv->totweight > 1) {
						defvert_remove_group(dv, dw); /* dw can be NULL */
					}
				}
			}
		}

		MEM_freeN(dvert_array);
	}
}

static void vgroup_clean_all(Object *ob, const float epsilon, const int keep_single)
{
	MDeformVert **dvert_array=NULL;
	int i, dvert_tot=0;
	
	Mesh *me = ob->data;
	const int use_vert_sel= (me->editflag & ME_EDIT_VERT_SEL) != 0;

	ED_vgroup_give_parray(ob->data, &dvert_array, &dvert_tot, use_vert_sel);

	if (dvert_array) {
		MDeformVert *dv;
		MDeformWeight *dw;

		for(i = 0; i < dvert_tot; i++) {
			int j;

			/* incase its not selected */
			if (!(dv = dvert_array[i])) {
				continue;
			}

			j= dv->totweight;

			while(j--) {

				if(keep_single && dv->totweight == 1)
					break;

				dw= dv->dw + j;

				if(dw->weight <= epsilon) {
					defvert_remove_group(dv, dw);
				}
			}
		}

		MEM_freeN(dvert_array);
	}
}


static void dvert_mirror_op(MDeformVert *dvert, MDeformVert *dvert_mirr,
                            const char sel, const char sel_mirr,
                            const int *flip_map, const int flip_map_len,
                            const short mirror_weights, const short flip_vgroups,
                            const short all_vgroups, const int act_vgroup)
{
	BLI_assert(sel || sel_mirr);

	if(sel_mirr && sel) {
		/* swap */
		if(mirror_weights) {
			if (all_vgroups) {
				SWAP(MDeformVert, *dvert, *dvert_mirr);
			}
			else {
				MDeformWeight *dw=      defvert_find_index(dvert, act_vgroup);
				MDeformWeight *dw_mirr= defvert_find_index(dvert_mirr, act_vgroup);

				if (dw || dw_mirr) {
					if (dw_mirr == NULL)
						dw_mirr= defvert_verify_index(dvert_mirr, act_vgroup);
					if (dw == NULL)
						dw= defvert_verify_index(dvert, act_vgroup);

					SWAP(float, dw->weight, dw_mirr->weight);
				}
			}
		}

		if(flip_vgroups) {
			defvert_flip(dvert, flip_map, flip_map_len);
			defvert_flip(dvert_mirr, flip_map, flip_map_len);
		}
	}
	else {
		/* dvert should always be the target, only swaps pointer */
		if(sel_mirr) {
			SWAP(MDeformVert *, dvert, dvert_mirr);
		}

		if(mirror_weights) {
			if (all_vgroups) {
				defvert_copy(dvert, dvert_mirr);
			}
			else {
				defvert_copy_index(dvert, dvert_mirr, act_vgroup);
			}
		}

		/* flip map already modified for 'all_vgroups' */
		if(flip_vgroups) {
			defvert_flip(dvert, flip_map, flip_map_len);
		}
	}
}

/* TODO, vgroup locking */
/* TODO, face masking */
void ED_vgroup_mirror(Object *ob, const short mirror_weights, const short flip_vgroups, const short all_vgroups)
{

#define VGROUP_MIRR_OP                                                        \
        dvert_mirror_op(dvert, dvert_mirr,                                    \
                        sel, sel_mirr,                                        \
                        flip_map, flip_map_len,                               \
                        mirror_weights, flip_vgroups,                         \
                        all_vgroups, def_nr                                   \
                        )

	EditVert *eve, *eve_mirr;
	MDeformVert *dvert, *dvert_mirr;
	short sel, sel_mirr;
	int	*flip_map, flip_map_len;
	const int def_nr= ob->actdef-1;

	if ( (mirror_weights==0 && flip_vgroups==0) ||
	     (BLI_findlink(&ob->defbase, def_nr) == NULL) )
	{
		return;
	}

	if (flip_vgroups) {
		flip_map= all_vgroups ?
					defgroup_flip_map(ob, &flip_map_len, FALSE) :
					defgroup_flip_map_single(ob, &flip_map_len, FALSE, def_nr);

		BLI_assert(flip_map != NULL);

		if (flip_map == NULL) {
			/* something went wrong!, possibly no groups */
			return;
		}
	}
	else {
		flip_map= NULL;
		flip_map_len= 0;
	}

	/* only the active group */
	if(ob->type == OB_MESH) {
		Mesh *me= ob->data;
		EditMesh *em = BKE_mesh_get_editmesh(me);

		if (em) {
			if(!CustomData_has_layer(&em->vdata, CD_MDEFORMVERT)) {
				goto cleanup;
			}

			EM_cache_x_mirror_vert(ob, em);

			/* Go through the list of editverts and assign them */
			for(eve=em->verts.first; eve; eve=eve->next){
				if((eve_mirr=eve->tmp.v)) {
					sel= eve->f & SELECT;
					sel_mirr= eve_mirr->f & SELECT;

					if((sel || sel_mirr) && (eve != eve_mirr)) {
						dvert= CustomData_em_get(&em->vdata, eve->data, CD_MDEFORMVERT);
						dvert_mirr= CustomData_em_get(&em->vdata, eve_mirr->data, CD_MDEFORMVERT);
						if(dvert && dvert_mirr) {
							VGROUP_MIRR_OP;
						}
					}

					eve->tmp.v= eve_mirr->tmp.v= NULL;
				}
			}
			BKE_mesh_end_editmesh(me, em);
		}
		else {
			/* object mode / weight paint */
			MVert *mv, *mv_mirr;
			int vidx, vidx_mirr;
			const int use_vert_sel= (me->editflag & ME_EDIT_VERT_SEL) != 0;

			if (me->dvert == NULL) {
				goto cleanup;
			}

			if (!use_vert_sel) {
				sel= sel_mirr= TRUE;
			}

			/* tag verts we have used */
			for(vidx= 0, mv= me->mvert; vidx < me->totvert; vidx++, mv++) {
				mv->flag &= ~ME_VERT_TMP_TAG;
			}

			for(vidx= 0, mv= me->mvert; vidx < me->totvert; vidx++, mv++) {
				if (    ((mv->flag & ME_VERT_TMP_TAG) == 0) &&
				        ((vidx_mirr= mesh_get_x_mirror_vert(ob, vidx)) != -1) &&
				        (vidx != vidx_mirr) &&
				        ((((mv_mirr= me->mvert + vidx_mirr)->flag) & ME_VERT_TMP_TAG) == 0))
				{

					if (use_vert_sel) {
						sel= mv->flag & SELECT;
						sel_mirr= mv_mirr->flag & SELECT;
					}

					if (sel || sel_mirr) {
						dvert= &me->dvert[vidx];
						dvert_mirr= &me->dvert[vidx_mirr];

						VGROUP_MIRR_OP;
					}

					mv->flag |= ME_VERT_TMP_TAG;
					mv_mirr->flag |= ME_VERT_TMP_TAG;
				}
			}
		}
	}
	else if (ob->type == OB_LATTICE) {
		Lattice *lt= vgroup_edit_lattice(ob);
		int i1, i2;
		int u, v, w;
		int pntsu_half;
		/* half but found up odd value */

		if(lt->pntsu == 1 || lt->dvert == NULL) {
			goto cleanup;
		}

		/* unlike editmesh we know that by only looping over the first hald of
		 * the 'u' indicies it will cover all points except the middle which is
		 * ok in this case */
		pntsu_half= lt->pntsu / 2;

		for(w=0; w<lt->pntsw; w++) {
			for(v=0; v<lt->pntsv; v++) {
				for(u=0; u<pntsu_half; u++) {
					int u_inv= (lt->pntsu - 1) - u;
					if(u != u_inv) {
						BPoint *bp, *bp_mirr;

						i1= LT_INDEX(lt, u, v, w);
						i2= LT_INDEX(lt, u_inv, v, w);

						bp= &lt->def[i1];
						bp_mirr= &lt->def[i2];

						sel= bp->f1 & SELECT;
						sel_mirr= bp_mirr->f1 & SELECT;

						if(sel || sel_mirr) {
							dvert= &lt->dvert[i1];
							dvert_mirr= &lt->dvert[i2];

							VGROUP_MIRR_OP;
						}
					}
				}
			}
		}
	}

cleanup:
	if (flip_map) MEM_freeN(flip_map);

#undef VGROUP_MIRR_OP

}

static void vgroup_remap_update_users(Object *ob, int *map)
{
	ExplodeModifierData *emd;
	ModifierData *md;
	ParticleSystem *psys;
	ClothModifierData *clmd;
	ClothSimSettings *clsim;
	int a;

	/* these cases don't use names to refer to vertex groups, so when
	 * they get deleted the numbers get out of sync, this corrects that */

	if(ob->soft)
		ob->soft->vertgroup= map[ob->soft->vertgroup];

	for(md=ob->modifiers.first; md; md=md->next) {
		if(md->type == eModifierType_Explode) {
			emd= (ExplodeModifierData*)md;
			emd->vgroup= map[emd->vgroup];
		}
		else if(md->type == eModifierType_Cloth) {
			clmd= (ClothModifierData*)md;
			clsim= clmd->sim_parms;

			if(clsim) {
				clsim->vgroup_mass= map[clsim->vgroup_mass];
				clsim->vgroup_bend= map[clsim->vgroup_bend];
				clsim->vgroup_struct= map[clsim->vgroup_struct];
			}
		}
	}

	for(psys=ob->particlesystem.first; psys; psys=psys->next) {
		for(a=0; a<PSYS_TOT_VG; a++)
			psys->vgroup[a]= map[psys->vgroup[a]];
	}
}


static void vgroup_delete_update_users(Object *ob, int id)
{
	int i, defbase_tot= BLI_countlist(&ob->defbase) + 1;
	int *map= MEM_mallocN(sizeof(int) * defbase_tot, "vgroup del");

	map[id]= map[0]= 0;
	for(i=1; i<id; i++) map[i]=i;
	for(i=id+1; i<defbase_tot; i++) map[i]=i-1;

	vgroup_remap_update_users(ob, map);
	MEM_freeN(map);
}


static void vgroup_delete_object_mode(Object *ob, bDeformGroup *dg)
{
	MDeformVert *dvert_array=NULL;
	int dvert_tot=0;
	const int def_nr= BLI_findindex(&ob->defbase, dg);

	assert(def_nr > -1);

	ED_vgroup_give_array(ob->data, &dvert_array, &dvert_tot);

	if(dvert_array) {
		int i, j;
		MDeformVert *dv;
		for(i= 0, dv= dvert_array; i < dvert_tot; i++, dv++) {
			MDeformWeight *dw;

			dw= defvert_find_index(dv, def_nr);
			defvert_remove_group(dv, dw); /* dw can be NULL */

			/* inline, make into a function if anything else needs to do this */
			for(j = 0; j < dv->totweight; j++) {
				if(dv->dw[j].def_nr > def_nr) {
					dv->dw[j].def_nr--;
				}
			}
			/* done */
		}
	}

	vgroup_delete_update_users(ob, def_nr + 1);

	/* Remove the group */
	BLI_freelinkN(&ob->defbase, dg);

	/* Update the active deform index if necessary */
	if(ob->actdef > def_nr)
		ob->actdef--;
	if(ob->actdef < 1 && ob->defbase.first)
		ob->actdef= 1;

}

/* only in editmode */
/* removes from active defgroup, if allverts==0 only selected vertices */
static void vgroup_active_remove_verts(Object *ob, const int allverts, bDeformGroup *dg)
{
	MDeformVert *dv;
	const int def_nr= BLI_findindex(&ob->defbase, dg);

	if(ob->type == OB_MESH) {
		Mesh *me= ob->data;

		if (me->edit_mesh) {
			EditVert *eve;
			EditMesh *em = BKE_mesh_get_editmesh(me);

			for (eve=em->verts.first; eve; eve=eve->next) {
				dv= CustomData_em_get(&em->vdata, eve->data, CD_MDEFORMVERT);

				if (dv && dv->dw && (allverts || (eve->f & SELECT))) {
					MDeformWeight *dw = defvert_find_index(dv, def_nr);
					defvert_remove_group(dv, dw); /* dw can be NULL */
				}
			}
			BKE_mesh_end_editmesh(me, em);
		}
		else {
			MVert *mv;
			MDeformVert *dv;
			int i;

			if (!me->dvert) {
				ED_vgroup_data_create(&me->id);
			}

			mv = me->mvert;
			dv = me->dvert;

			for (i=0; i<me->totvert; i++, mv++, dv++) {
				if (mv->flag & SELECT) {
					if (dv->dw && (allverts || (mv->flag & SELECT))) {
						MDeformWeight *dw = defvert_find_index(dv, def_nr);
						defvert_remove_group(dv, dw); /* dw can be NULL */
					}
				}
			}
		}
	}
	else if(ob->type == OB_LATTICE) {
		Lattice *lt= vgroup_edit_lattice(ob);
		
		if(lt->dvert) {
			BPoint *bp;
			int i, tot= lt->pntsu*lt->pntsv*lt->pntsw;
				
			for(i=0, bp= lt->def; i<tot; i++, bp++) {
				if(allverts || (bp->f1 & SELECT)) {
					MDeformWeight *dw;

					dv= &lt->dvert[i];

					dw = defvert_find_index(dv, def_nr);
					defvert_remove_group(dv, dw); /* dw can be NULL */
				}
			}
		}
	}
}

static void vgroup_delete_edit_mode(Object *ob, bDeformGroup *dg)
{
	int i;
	const int dg_index= BLI_findindex(&ob->defbase, dg);

	assert(dg_index > -1);

	/* Make sure that no verts are using this group */
	vgroup_active_remove_verts(ob, TRUE, dg);

	/* Make sure that any verts with higher indices are adjusted accordingly */
	if(ob->type==OB_MESH) {
		Mesh *me= ob->data;
		EditMesh *em = BKE_mesh_get_editmesh(me);
		EditVert *eve;
		MDeformVert *dvert;
		
		for(eve=em->verts.first; eve; eve=eve->next){
			dvert= CustomData_em_get(&em->vdata, eve->data, CD_MDEFORMVERT);

			if(dvert)
				for(i=0; i<dvert->totweight; i++)
					if(dvert->dw[i].def_nr > dg_index)
						dvert->dw[i].def_nr--;
		}
		BKE_mesh_end_editmesh(me, em);
	}
	else if(ob->type==OB_LATTICE) {
		Lattice *lt= vgroup_edit_lattice(ob);
		BPoint *bp;
		MDeformVert *dvert= lt->dvert;
		int a, tot;
		
		if(dvert) {
			tot= lt->pntsu*lt->pntsv*lt->pntsw;
			for(a=0, bp= lt->def; a<tot; a++, bp++, dvert++) {
				for(i=0; i<dvert->totweight; i++){
					if(dvert->dw[i].def_nr > dg_index)
						dvert->dw[i].def_nr--;
				}
			}
		}
	}

	vgroup_delete_update_users(ob, dg_index + 1);

	/* Remove the group */
	BLI_freelinkN (&ob->defbase, dg);

	/* Update the active deform index if necessary */
	if(ob->actdef > dg_index)
		ob->actdef--;
	if(ob->actdef < 1 && ob->defbase.first)
		ob->actdef= 1;

	/* remove all dverts */
	if(ob->defbase.first == NULL) {
		if(ob->type==OB_MESH) {
			Mesh *me= ob->data;
			CustomData_free_layer_active(&me->vdata, CD_MDEFORMVERT, me->totvert);
			me->dvert= NULL;
		}
		else if(ob->type==OB_LATTICE) {
			Lattice *lt= vgroup_edit_lattice(ob);
			if(lt->dvert) {
				MEM_freeN(lt->dvert);
				lt->dvert= NULL;
			}
		}
	}
}

static int vgroup_object_in_edit_mode(Object *ob)
{
	if(ob->type == OB_MESH)
		return (((Mesh*)ob->data)->edit_mesh != NULL);
	else if(ob->type == OB_LATTICE)
		return (((Lattice*)ob->data)->editlatt != NULL);
	
	return 0;
}

static int vgroup_object_in_wpaint_vert_select(Object *ob)
{
	if (ob->type == OB_MESH) {
		Mesh *me = ob->data;
		return ( (ob->mode & OB_MODE_WEIGHT_PAINT) &&
		         (me->edit_mesh == NULL) &&
		         (ME_EDIT_PAINT_SEL_MODE(me) == SCE_SELECT_VERTEX) );
	}

	return 0;
}

static void vgroup_delete(Object *ob)
{
	bDeformGroup *dg = BLI_findlink(&ob->defbase, ob->actdef-1);
	if(!dg)
		return;

	if(vgroup_object_in_edit_mode(ob))
		vgroup_delete_edit_mode(ob, dg);
	else
		vgroup_delete_object_mode(ob, dg);
}

static void vgroup_delete_all(Object *ob)
{
	/* Remove all DVerts */
	if(ob->type==OB_MESH) {
		Mesh *me= ob->data;
		CustomData_free_layer_active(&me->vdata, CD_MDEFORMVERT, me->totvert);
		me->dvert= NULL;
	}
	else if(ob->type==OB_LATTICE) {
		Lattice *lt= vgroup_edit_lattice(ob);
		if(lt->dvert) {
			MEM_freeN(lt->dvert);
			lt->dvert= NULL;
		}
	}
	
	/* Remove all DefGroups */
	BLI_freelistN(&ob->defbase);
	
	/* Fix counters/indices */
	ob->actdef= 0;
}

/* only in editmode */
static void vgroup_assign_verts(Object *ob, const float weight)
{
	MDeformVert *dv;
	const int def_nr= ob->actdef-1;

	if(!BLI_findlink(&ob->defbase, def_nr))
		return;

	if(ob->type == OB_MESH) {
		Mesh *me= ob->data;
		if (me->edit_mesh) {
			EditMesh *em = BKE_mesh_get_editmesh(me);
			EditVert *eve;

			if(!CustomData_has_layer(&em->vdata, CD_MDEFORMVERT))
				EM_add_data_layer(em, &em->vdata, CD_MDEFORMVERT, NULL);

			/* Go through the list of editverts and assign them */
			for (eve=em->verts.first; eve; eve=eve->next) {
				if (eve->f & SELECT) {
					MDeformWeight *dw;
					dv= CustomData_em_get(&em->vdata, eve->data, CD_MDEFORMVERT); /* can be NULL */
					dw= defvert_verify_index(dv, def_nr);
					if (dw) {
						dw->weight= weight;
					}
				}
			}
			BKE_mesh_end_editmesh(me, em);
		}
		else {
			MVert *mv;
			MDeformVert *dv;
			int i;

			if (!me->dvert) {
				ED_vgroup_data_create(&me->id);
			}

			mv = me->mvert;
			dv = me->dvert;

			for (i=0; i<me->totvert; i++, mv++, dv++) {
				if (mv->flag & SELECT) {
					MDeformWeight *dw;
					dw= defvert_verify_index(dv, def_nr);
					if (dw) {
						dw->weight= weight;
					}
				}
			}
		}
	}
	else if(ob->type == OB_LATTICE) {
		Lattice *lt= vgroup_edit_lattice(ob);
		BPoint *bp;
		int a, tot;

		if(lt->dvert==NULL)
			ED_vgroup_data_create(&lt->id);

		dv= lt->dvert;

		tot= lt->pntsu*lt->pntsv*lt->pntsw;
		for(a=0, bp= lt->def; a<tot; a++, bp++, dv++) {
			if(bp->f1 & SELECT) {
				MDeformWeight *dw;

				dw= defvert_verify_index(dv, def_nr);
				if (dw) {
					dw->weight= weight;
				}
			}
		}
	}
}

/* only in editmode */
/* removes from all defgroup, if allverts==0 only selected vertices */
static void vgroup_remove_verts(Object *ob, int allverts)
{
	/* To prevent code redundancy, we just use vgroup_active_remove_verts, but that
	 * only operates on the active vgroup. So we iterate through all groups, by changing
	 * active group index
	 */
	bDeformGroup *dg;
	for(dg= ob->defbase.first; dg; dg= dg->next) {
		vgroup_active_remove_verts(ob, allverts, dg);
	}
}

/********************** vertex group operators *********************/

static int vertex_group_poll(bContext *C)
{
	Object *ob= ED_object_context(C);
	ID *data= (ob)? ob->data: NULL;
	return (ob && !ob->id.lib && OB_TYPE_SUPPORT_VGROUP(ob->type) && data && !data->lib);
}

static int UNUSED_FUNCTION(vertex_group_poll_edit)(bContext *C)
{
	Object *ob= ED_object_context(C);
	ID *data= (ob)? ob->data: NULL;

	if(!(ob && !ob->id.lib && data && !data->lib))
		return 0;

	return vgroup_object_in_edit_mode(ob);
}

/* editmode _or_ weight paint vertex sel */
static int vertex_group_poll_edit_or_wpaint_vert_select(bContext *C)
{
	Object *ob= ED_object_context(C);
	ID *data= (ob)? ob->data: NULL;

	if(!(ob && !ob->id.lib && data && !data->lib))
		return 0;

	return ( vgroup_object_in_edit_mode(ob) ||
	         vgroup_object_in_wpaint_vert_select(ob) );
}

static int vertex_group_add_exec(bContext *C, wmOperator *UNUSED(op))
{
	Object *ob= ED_object_context(C);

	ED_vgroup_add(ob);
	DAG_id_tag_update(&ob->id, OB_RECALC_DATA);
	WM_event_add_notifier(C, NC_GEOM|ND_DATA, ob->data);
	WM_event_add_notifier(C, NC_OBJECT|ND_DRAW, ob);
	
	return OPERATOR_FINISHED;
}

void OBJECT_OT_vertex_group_add(wmOperatorType *ot)
{
	/* identifiers */
	ot->name= "Add Vertex Group";
	ot->idname= "OBJECT_OT_vertex_group_add";
	
	/* api callbacks */
	ot->poll= vertex_group_poll;
	ot->exec= vertex_group_add_exec;

	/* flags */
	ot->flag= OPTYPE_REGISTER|OPTYPE_UNDO;
}

static int vertex_group_remove_exec(bContext *C, wmOperator *op)
{
	Object *ob= ED_object_context(C);

	if(RNA_boolean_get(op->ptr, "all"))
		vgroup_delete_all(ob);
	else
		vgroup_delete(ob);

	DAG_id_tag_update(&ob->id, OB_RECALC_DATA);
	WM_event_add_notifier(C, NC_GEOM|ND_DATA, ob->data);
	WM_event_add_notifier(C, NC_OBJECT|ND_DRAW, ob);
	
	return OPERATOR_FINISHED;
}

void OBJECT_OT_vertex_group_remove(wmOperatorType *ot)
{
	/* identifiers */
	ot->name= "Remove Vertex Group";
	ot->idname= "OBJECT_OT_vertex_group_remove";
	
	/* api callbacks */
	ot->poll= vertex_group_poll;
	ot->exec= vertex_group_remove_exec;

	/* flags */
	/* redo operator will fail in this case because vertex groups aren't stored
	   in local edit mode stack and toggling "all" property will lead to
	   all groups deleted without way to restore them (see [#29527], sergey) */
	ot->flag= /*OPTYPE_REGISTER|*/OPTYPE_UNDO;

	/* properties */
	RNA_def_boolean(ot->srna, "all", 0, "All", "Remove from all vertex groups");
}

static int vertex_group_assign_exec(bContext *C, wmOperator *op)
{
	ToolSettings *ts= CTX_data_tool_settings(C);
	Object *ob= ED_object_context(C);

	if(RNA_boolean_get(op->ptr, "new"))
		ED_vgroup_add(ob);

	vgroup_assign_verts(ob, ts->vgroup_weight);
	DAG_id_tag_update(&ob->id, OB_RECALC_DATA);
	WM_event_add_notifier(C, NC_GEOM|ND_DATA, ob->data);
	
	return OPERATOR_FINISHED;
}

void OBJECT_OT_vertex_group_assign(wmOperatorType *ot)
{
	/* identifiers */
	ot->name= "Assign Vertex Group";
	ot->idname= "OBJECT_OT_vertex_group_assign";
	
	/* api callbacks */
	ot->poll= vertex_group_poll_edit_or_wpaint_vert_select;
	ot->exec= vertex_group_assign_exec;

	/* flags */
	/* redo operator will fail in this case because vertex group assignment
	   isn't stored in local edit mode stack and toggling "new" property will
	   lead to creating plenty of new veretx groups (see [#29527], sergey) */
	ot->flag= /*OPTYPE_REGISTER|*/OPTYPE_UNDO;

	/* properties */
	RNA_def_boolean(ot->srna, "new", 0, "New", "Assign vertex to new vertex group");
}

static int vertex_group_remove_from_exec(bContext *C, wmOperator *op)
{
	Object *ob= ED_object_context(C);

	if(RNA_boolean_get(op->ptr, "all"))
		vgroup_remove_verts(ob, 0);
	else {
		bDeformGroup *dg= BLI_findlink(&ob->defbase, ob->actdef - 1);

		if(dg == NULL) {
			return OPERATOR_CANCELLED;
		}

		vgroup_active_remove_verts(ob, FALSE, dg);
	}

	DAG_id_tag_update(&ob->id, OB_RECALC_DATA);
	WM_event_add_notifier(C, NC_GEOM|ND_DATA, ob->data);

	return OPERATOR_FINISHED;
}

void OBJECT_OT_vertex_group_remove_from(wmOperatorType *ot)
{
	/* identifiers */
	ot->name= "Remove from Vertex Group";
	ot->idname= "OBJECT_OT_vertex_group_remove_from";

	/* api callbacks */
	ot->poll= vertex_group_poll_edit_or_wpaint_vert_select;
	ot->exec= vertex_group_remove_from_exec;

	/* flags */
	/* redo operator will fail in this case because vertex groups ssignment
	   isn't stored in local edit mode stack and toggling "all" property will lead to
	   removing vertices from all groups (see [#29527], sergey) */
	ot->flag= /*OPTYPE_REGISTER|*/OPTYPE_UNDO;

	/* properties */
	RNA_def_boolean(ot->srna, "all", 0, "All", "Remove from all vertex groups");
}

static int vertex_group_select_exec(bContext *C, wmOperator *UNUSED(op))
{
	Object *ob= ED_object_context(C);

	if(!ob || ob->id.lib)
		return OPERATOR_CANCELLED;

	vgroup_select_verts(ob, 1);
	WM_event_add_notifier(C, NC_GEOM|ND_SELECT, ob->data);

	return OPERATOR_FINISHED;
}

void OBJECT_OT_vertex_group_select(wmOperatorType *ot)
{
	/* identifiers */
	ot->name= "Select Vertex Group";
	ot->idname= "OBJECT_OT_vertex_group_select";

	/* api callbacks */
	ot->poll= vertex_group_poll_edit_or_wpaint_vert_select;
	ot->exec= vertex_group_select_exec;

	/* flags */
	ot->flag= OPTYPE_REGISTER|OPTYPE_UNDO;
}

static int vertex_group_deselect_exec(bContext *C, wmOperator *UNUSED(op))
{
	Object *ob= ED_object_context(C);

	vgroup_select_verts(ob, 0);
	WM_event_add_notifier(C, NC_GEOM|ND_SELECT, ob->data);

	return OPERATOR_FINISHED;
}

void OBJECT_OT_vertex_group_deselect(wmOperatorType *ot)
{
	/* identifiers */
	ot->name= "Deselect Vertex Group";
	ot->idname= "OBJECT_OT_vertex_group_deselect";

	/* api callbacks */
	ot->poll= vertex_group_poll_edit_or_wpaint_vert_select;
	ot->exec= vertex_group_deselect_exec;

	/* flags */
	ot->flag= OPTYPE_REGISTER|OPTYPE_UNDO;
}

static int vertex_group_copy_exec(bContext *C, wmOperator *UNUSED(op))
{
	Object *ob= ED_object_context(C);

	vgroup_duplicate(ob);
	DAG_id_tag_update(&ob->id, OB_RECALC_DATA);
	WM_event_add_notifier(C, NC_OBJECT|ND_DRAW, ob);
	WM_event_add_notifier(C, NC_GEOM|ND_DATA, ob->data);

	return OPERATOR_FINISHED;
}

void OBJECT_OT_vertex_group_copy(wmOperatorType *ot)
{
	/* identifiers */
	ot->name= "Copy Vertex Group";
	ot->idname= "OBJECT_OT_vertex_group_copy";

	/* api callbacks */
	ot->poll= vertex_group_poll;
	ot->exec= vertex_group_copy_exec;

	/* flags */
	ot->flag= OPTYPE_REGISTER|OPTYPE_UNDO;
}

static int vertex_group_levels_exec(bContext *C, wmOperator *op)
{
	Object *ob= ED_object_context(C);
	
	float offset= RNA_float_get(op->ptr,"offset");
	float gain= RNA_float_get(op->ptr,"gain");
	
	vgroup_levels(ob, offset, gain);
	
	DAG_id_tag_update(&ob->id, OB_RECALC_DATA);
	WM_event_add_notifier(C, NC_OBJECT|ND_DRAW, ob);
	WM_event_add_notifier(C, NC_GEOM|ND_DATA, ob->data);
	
	return OPERATOR_FINISHED;
}

void OBJECT_OT_vertex_group_levels(wmOperatorType *ot)
{
	/* identifiers */
	ot->name= "Vertex Group Levels";
	ot->idname= "OBJECT_OT_vertex_group_levels";
	
	/* api callbacks */
	ot->poll= vertex_group_poll;
	ot->exec= vertex_group_levels_exec;
	
	/* flags */
	ot->flag= OPTYPE_REGISTER|OPTYPE_UNDO;
	
	RNA_def_float(ot->srna, "offset", 0.f, -1.0, 1.0, "Offset", "Value to add to weights", -1.0f, 1.f);
	RNA_def_float(ot->srna, "gain", 1.f, 0.f, FLT_MAX, "Gain", "Value to multiply weights by", 0.0f, 10.f);
}

static int vertex_group_normalize_exec(bContext *C, wmOperator *UNUSED(op))
{
	Object *ob= ED_object_context(C);

	vgroup_normalize(ob);

	DAG_id_tag_update(&ob->id, OB_RECALC_DATA);
	WM_event_add_notifier(C, NC_OBJECT|ND_DRAW, ob);
	WM_event_add_notifier(C, NC_GEOM|ND_DATA, ob->data);

	return OPERATOR_FINISHED;
}

void OBJECT_OT_vertex_group_normalize(wmOperatorType *ot)
{
	/* identifiers */
	ot->name= "Normalize Vertex Group";
	ot->idname= "OBJECT_OT_vertex_group_normalize";

	/* api callbacks */
	ot->poll= vertex_group_poll;
	ot->exec= vertex_group_normalize_exec;

	/* flags */
	ot->flag= OPTYPE_REGISTER|OPTYPE_UNDO;
}

static int vertex_group_normalize_all_exec(bContext *C, wmOperator *op)
{
	Object *ob= ED_object_context(C);
	int lock_active= RNA_boolean_get(op->ptr,"lock_active");

	vgroup_normalize_all(ob, lock_active);

	DAG_id_tag_update(&ob->id, OB_RECALC_DATA);
	WM_event_add_notifier(C, NC_OBJECT|ND_DRAW, ob);
	WM_event_add_notifier(C, NC_GEOM|ND_DATA, ob->data);

	return OPERATOR_FINISHED;
}

void OBJECT_OT_vertex_group_normalize_all(wmOperatorType *ot)
{
	/* identifiers */
	ot->name= "Normalize All Vertex Groups";
	ot->idname= "OBJECT_OT_vertex_group_normalize_all";

	/* api callbacks */
	ot->poll= vertex_group_poll;
	ot->exec= vertex_group_normalize_all_exec;

	/* flags */
	ot->flag= OPTYPE_REGISTER|OPTYPE_UNDO;

	RNA_def_boolean(ot->srna, "lock_active", TRUE, "Lock Active",
	                "Keep the values of the active group while normalizing others");
}

static int vertex_group_fix_exec(bContext *C, wmOperator *op)
{
	Object *ob= CTX_data_active_object(C);
	Scene *scene= CTX_data_scene(C);
	
	float distToBe= RNA_float_get(op->ptr, "dist");
	float strength= RNA_float_get(op->ptr, "strength");
	float cp= RNA_float_get(op->ptr, "accuracy");
	ModifierData *md= ob->modifiers.first;

	while(md) {
		if(md->type == eModifierType_Mirror && (md->mode&eModifierMode_Realtime)) {
			break;
		}
		md = md->next;
	}
	
	if(md && md->type == eModifierType_Mirror) {
		BKE_report(op->reports, RPT_ERROR_INVALID_CONTEXT, "This operator does not support an active mirror modifier");
		return OPERATOR_CANCELLED;
	}
	vgroup_fix(scene, ob, distToBe, strength, cp);
	
	DAG_id_tag_update(&ob->id, OB_RECALC_DATA);
	WM_event_add_notifier(C, NC_OBJECT|ND_DRAW, ob);
	WM_event_add_notifier(C, NC_GEOM|ND_DATA, ob->data);
	
	return OPERATOR_FINISHED;
}

void OBJECT_OT_vertex_group_fix(wmOperatorType *ot)
{
	/* identifiers */
	ot->name= "Fix Vertex Group Deform";
	ot->idname= "OBJECT_OT_vertex_group_fix";
	ot->description= "Modify the position of selected vertices by changing only their respective "
	                 "groups' weights (this tool may be slow for many vertices)";
	
	/* api callbacks */
	ot->poll= vertex_group_poll;
	ot->exec= vertex_group_fix_exec;
	
	/* flags */
	ot->flag= OPTYPE_REGISTER|OPTYPE_UNDO;
	RNA_def_float(ot->srna, "dist", 0.0f, -FLT_MAX, FLT_MAX, "Distance", "The distance to move to", -10.0f, 10.0f);
	RNA_def_float(ot->srna, "strength", 1.f, -2.0f, FLT_MAX, "Strength",
	              "The distance moved can be changed by this multiplier", -2.0f, 2.0f);
	RNA_def_float(ot->srna, "accuracy", 1.0f, 0.05f, FLT_MAX, "Change Sensitivity",
	              "Change the amount weights are altered with each iteration: lower values are slower", 0.05f, 1.f);
}


static int vertex_group_lock_exec(bContext *C, wmOperator *op)
{
	Object *ob= CTX_data_active_object(C);

	int action = RNA_enum_get(op->ptr, "action");

	vgroup_lock_all(ob, action);

	return OPERATOR_FINISHED;
}

void OBJECT_OT_vertex_group_lock(wmOperatorType *ot)
{
	/* identifiers */
	ot->name= "Change the Lock On Vertex Groups";
	ot->idname= "OBJECT_OT_vertex_group_lock";

	/* api callbacks */
	ot->poll= vertex_group_poll;
	ot->exec= vertex_group_lock_exec;

	/* flags */
	ot->flag= OPTYPE_REGISTER|OPTYPE_UNDO;

	WM_operator_properties_select_all(ot);
}

static int vertex_group_invert_exec(bContext *C, wmOperator *op)
{
	Object *ob= ED_object_context(C);
	int auto_assign= RNA_boolean_get(op->ptr,"auto_assign");
	int auto_remove= RNA_boolean_get(op->ptr,"auto_remove");

	vgroup_invert(ob, auto_assign, auto_remove);
	DAG_id_tag_update(&ob->id, OB_RECALC_DATA);
	WM_event_add_notifier(C, NC_OBJECT|ND_DRAW, ob);
	WM_event_add_notifier(C, NC_GEOM|ND_DATA, ob->data);

	return OPERATOR_FINISHED;
}

void OBJECT_OT_vertex_group_invert(wmOperatorType *ot)
{
	/* identifiers */
	ot->name= "Invert Vertex Group";
	ot->idname= "OBJECT_OT_vertex_group_invert";

	/* api callbacks */
	ot->poll= vertex_group_poll;
	ot->exec= vertex_group_invert_exec;

	/* flags */
	ot->flag= OPTYPE_REGISTER|OPTYPE_UNDO;

	RNA_def_boolean(ot->srna, "auto_assign", TRUE, "Add Weights",
	                "Add verts from groups that have zero weight before inverting");
	RNA_def_boolean(ot->srna, "auto_remove", TRUE, "Remove Weights",
	                "Remove verts from groups that have zero weight after inverting");
}


static int vertex_group_blend_exec(bContext *C, wmOperator *UNUSED(op))
{
	Object *ob= ED_object_context(C);

	vgroup_blend(ob);

	DAG_id_tag_update(&ob->id, OB_RECALC_DATA);
	WM_event_add_notifier(C, NC_OBJECT|ND_DRAW, ob);
	WM_event_add_notifier(C, NC_GEOM|ND_DATA, ob->data);

	return OPERATOR_FINISHED;
}

void OBJECT_OT_vertex_group_blend(wmOperatorType *ot)
{
	/* identifiers */
	ot->name= "Blend Vertex Group";
	ot->idname= "OBJECT_OT_vertex_group_blend";
	ot->description= "";

	/* api callbacks */
	ot->poll= vertex_group_poll;
	ot->exec= vertex_group_blend_exec;

	/* flags */
	ot->flag= OPTYPE_REGISTER|OPTYPE_UNDO;
}


static int vertex_group_clean_exec(bContext *C, wmOperator *op)
{
	Object *ob= ED_object_context(C);

	float limit= RNA_float_get(op->ptr,"limit");
	int all_groups= RNA_boolean_get(op->ptr,"all_groups");
	int keep_single= RNA_boolean_get(op->ptr,"keep_single");

	if(all_groups)	vgroup_clean_all(ob, limit, keep_single);
	else			vgroup_clean(ob, limit, keep_single);

	DAG_id_tag_update(&ob->id, OB_RECALC_DATA);
	WM_event_add_notifier(C, NC_OBJECT|ND_DRAW, ob);
	WM_event_add_notifier(C, NC_GEOM|ND_DATA, ob->data);

	return OPERATOR_FINISHED;
}

void OBJECT_OT_vertex_group_clean(wmOperatorType *ot)
{
	/* identifiers */
	ot->name= "Clean Vertex Group";
	ot->idname= "OBJECT_OT_vertex_group_clean";
	ot->description= "Remove Vertex Group assignments which aren't required";

	/* api callbacks */
	ot->poll= vertex_group_poll;
	ot->exec= vertex_group_clean_exec;

	/* flags */
	ot->flag= OPTYPE_REGISTER|OPTYPE_UNDO;

	RNA_def_float(ot->srna, "limit", 0.01f, 0.0f, 1.0, "Limit", "Remove weights under this limit", 0.001f, 0.99f);
	RNA_def_boolean(ot->srna, "all_groups", FALSE, "All Groups", "Clean all vertex groups");
	RNA_def_boolean(ot->srna, "keep_single", FALSE, "Keep Single",
	                "Keep verts assigned to at least one group when cleaning");
}


static int vertex_group_mirror_exec(bContext *C, wmOperator *op)
{
	Object *ob= ED_object_context(C);

	ED_vgroup_mirror(ob,
	                 RNA_boolean_get(op->ptr,"mirror_weights"),
	                 RNA_boolean_get(op->ptr,"flip_group_names"),
	                 RNA_boolean_get(op->ptr,"all_groups"));

	DAG_id_tag_update(&ob->id, OB_RECALC_DATA);
	WM_event_add_notifier(C, NC_OBJECT|ND_DRAW, ob);
	WM_event_add_notifier(C, NC_GEOM|ND_DATA, ob->data);

	return OPERATOR_FINISHED;
}

void OBJECT_OT_vertex_group_mirror(wmOperatorType *ot)
{
	/* identifiers */
	ot->name= "Mirror Vertex Group";
	ot->idname= "OBJECT_OT_vertex_group_mirror";
	ot->description= "Mirror all vertex groups, flip weights and/or names, editing only selected vertices, "
	                 "flipping when both sides are selected otherwise copy from unselected";

	/* api callbacks */
	ot->poll= vertex_group_poll;
	ot->exec= vertex_group_mirror_exec;

	/* flags */
	ot->flag= OPTYPE_REGISTER|OPTYPE_UNDO;

	/* properties */
	RNA_def_boolean(ot->srna, "mirror_weights", TRUE, "Mirror Weights", "Mirror weights");
	RNA_def_boolean(ot->srna, "flip_group_names", TRUE, "Flip Groups", "Flip vertex group names");
	RNA_def_boolean(ot->srna, "all_groups", FALSE, "All Groups", "Mirror all vertex groups weights");

}

static int vertex_group_copy_to_linked_exec(bContext *C, wmOperator *UNUSED(op))
{
	Scene *scene= CTX_data_scene(C);
	Object *ob= ED_object_context(C);
	Base *base;
	int retval= OPERATOR_CANCELLED;

	for(base=scene->base.first; base; base= base->next) {
		if(base->object->type==ob->type) {
			if(base->object!=ob && base->object->data==ob->data) {
				BLI_freelistN(&base->object->defbase);
				BLI_duplicatelist(&base->object->defbase, &ob->defbase);
				base->object->actdef= ob->actdef;

				DAG_id_tag_update(&base->object->id, OB_RECALC_DATA);
				WM_event_add_notifier(C, NC_OBJECT|ND_DRAW, base->object);
				WM_event_add_notifier(C, NC_GEOM|ND_DATA, base->object->data);

				retval = OPERATOR_FINISHED;
			}
		}
	}

	return retval;
}

void OBJECT_OT_vertex_group_copy_to_linked(wmOperatorType *ot)
{
	/* identifiers */
	ot->name= "Copy Vertex Groups to Linked";
	ot->idname= "OBJECT_OT_vertex_group_copy_to_linked";
	ot->description= "Copy Vertex Groups to all users of the same Geometry data";

	/* api callbacks */
	ot->poll= vertex_group_poll;
	ot->exec= vertex_group_copy_to_linked_exec;

	/* flags */
	ot->flag= OPTYPE_REGISTER|OPTYPE_UNDO;
}

static int vertex_group_copy_to_selected_exec(bContext *C, wmOperator *op)
{
	Object *obact= ED_object_context(C);
	int change= 0;
	int fail= 0;

	CTX_DATA_BEGIN(C, Object*, ob, selected_editable_objects)
	{
		if(obact != ob) {
			if(ED_vgroup_copy_array(ob, obact)) change++;
			else                                fail++;
		}
	}
	CTX_DATA_END;

	if((change == 0 && fail == 0) || fail) {
		BKE_reportf(op->reports, RPT_ERROR,
		            "Copy to VGroups to Selected warning done %d, failed %d, object data must have matching indicies",
		            change, fail);
	}

	return OPERATOR_FINISHED;
}


void OBJECT_OT_vertex_group_copy_to_selected(wmOperatorType *ot)
{
	/* identifiers */
	ot->name= "Copy Vertex Group to Selected";
	ot->idname= "OBJECT_OT_vertex_group_copy_to_selected";
	ot->description= "Copy Vertex Groups to other selected objects with matching indices";

	/* api callbacks */
	ot->poll= vertex_group_poll;
	ot->exec= vertex_group_copy_to_selected_exec;

	/* flags */
	ot->flag= OPTYPE_REGISTER|OPTYPE_UNDO;
}

static EnumPropertyItem vgroup_items[]= {
	{0, NULL, 0, NULL, NULL}};

static int set_active_group_exec(bContext *C, wmOperator *op)
{
	Object *ob= ED_object_context(C);
	int nr= RNA_enum_get(op->ptr, "group");

	BLI_assert(nr+1 >= 0);
	ob->actdef= nr+1;

	DAG_id_tag_update(&ob->id, OB_RECALC_DATA);
	WM_event_add_notifier(C, NC_GEOM|ND_DATA, ob);

	return OPERATOR_FINISHED;
}

static EnumPropertyItem *vgroup_itemf(bContext *C, PointerRNA *UNUSED(ptr), PropertyRNA *UNUSED(prop), int *free)
{	
	Object *ob= ED_object_context(C);
	EnumPropertyItem tmp = {0, "", 0, "", ""};
	EnumPropertyItem *item= NULL;
	bDeformGroup *def;
	int a, totitem= 0;
	
	if(!ob)
		return vgroup_items;
	
	for(a=0, def=ob->defbase.first; def; def=def->next, a++) {
		tmp.value= a;
		tmp.icon= ICON_GROUP_VERTEX;
		tmp.identifier= def->name;
		tmp.name= def->name;
		RNA_enum_item_add(&item, &totitem, &tmp);
	}

	RNA_enum_item_end(&item, &totitem);
	*free= 1;

	return item;
}

void OBJECT_OT_vertex_group_set_active(wmOperatorType *ot)
{
	PropertyRNA *prop;

	/* identifiers */
	ot->name= "Set Active Vertex Group";
	ot->idname= "OBJECT_OT_vertex_group_set_active";
	ot->description= "Set the active vertex group";

	/* api callbacks */
	ot->poll= vertex_group_poll;
	ot->exec= set_active_group_exec;
	ot->invoke= WM_menu_invoke;

	/* flags */
	ot->flag= OPTYPE_REGISTER|OPTYPE_UNDO;

	/* properties */
	prop= RNA_def_enum(ot->srna, "group", vgroup_items, 0, "Group", "Vertex group to set as active");
	RNA_def_enum_funcs(prop, vgroup_itemf);
	ot->prop= prop;
}

/*creates the name_array parameter for vgroup_do_remap, call this before fiddling
  with the order of vgroups then call vgroup_do_remap after*/
static char *vgroup_init_remap(Object *ob)
{
	bDeformGroup *def;
	int defbase_tot = BLI_countlist(&ob->defbase);
	char *name_array= MEM_mallocN(MAX_VGROUP_NAME * sizeof(char) * defbase_tot, "sort vgroups");
	char *name;

	name= name_array;
	for(def = ob->defbase.first; def; def=def->next) {
		BLI_strncpy(name, def->name, MAX_VGROUP_NAME);
		name += MAX_VGROUP_NAME;
	}

	return name_array;
}

static int vgroup_do_remap(Object *ob, char *name_array, wmOperator *op)
{
	MDeformVert *dvert= NULL;
	bDeformGroup *def;
	int defbase_tot = BLI_countlist(&ob->defbase);

	/* needs a dummy index at the start*/
	int *sort_map_update= MEM_mallocN(sizeof(int) * (defbase_tot + 1), "sort vgroups");
	int *sort_map= sort_map_update + 1;

	char *name;
	int i;

	name= name_array;
	for(def= ob->defbase.first, i=0; def; def=def->next, i++){
		sort_map[i]= BLI_findstringindex(&ob->defbase, name, offsetof(bDeformGroup, name));
		name += MAX_VGROUP_NAME;

		BLI_assert(sort_map[i] != -1);
	}

	if(ob->mode == OB_MODE_EDIT) {
		if(ob->type==OB_MESH) {
			EditMesh *em = BKE_mesh_get_editmesh(ob->data);
			EditVert *eve;

			for(eve=em->verts.first; eve; eve=eve->next){
				dvert= CustomData_em_get(&em->vdata, eve->data, CD_MDEFORMVERT);
				if(dvert && dvert->totweight){
					defvert_remap(dvert, sort_map, defbase_tot);
				}
			}
		}
		else {
			BKE_report(op->reports, RPT_ERROR, "Editmode lattice isnt supported yet");
			MEM_freeN(sort_map_update);
			return OPERATOR_CANCELLED;
		}
	}
	else {
		int dvert_tot=0;

		ED_vgroup_give_array(ob->data, &dvert, &dvert_tot);

		/*create as necassary*/
		while(dvert && dvert_tot--) {
			if(dvert->totweight)
				defvert_remap(dvert, sort_map, defbase_tot);
			dvert++;
		}
	}

	/* update users */
	for(i=0; i<defbase_tot; i++)
		sort_map[i]++;

	sort_map_update[0]= 0;
	vgroup_remap_update_users(ob, sort_map_update);

	BLI_assert(sort_map_update[ob->actdef] >= 0);
	ob->actdef= sort_map_update[ob->actdef];
	
	MEM_freeN(sort_map_update);

	return OPERATOR_FINISHED;
}

static int vgroup_sort(void *def_a_ptr, void *def_b_ptr)
{
	bDeformGroup *def_a= (bDeformGroup *)def_a_ptr;
	bDeformGroup *def_b= (bDeformGroup *)def_b_ptr;

	return BLI_natstrcmp(def_a->name, def_b->name);
}

static int vertex_group_sort_exec(bContext *C, wmOperator *op)
{
	Object *ob= ED_object_context(C);
	char *name_array;
	int ret;

	/*init remapping*/
	name_array = vgroup_init_remap(ob);

	/*sort vgroup names*/
	BLI_sortlist(&ob->defbase, vgroup_sort);

	/*remap vgroup data to map to correct names*/
	ret = vgroup_do_remap(ob, name_array, op);

	if (ret != OPERATOR_CANCELLED) {
		DAG_id_tag_update(&ob->id, OB_RECALC_DATA);
		WM_event_add_notifier(C, NC_GEOM|ND_DATA, ob);
	}

	if (name_array) MEM_freeN(name_array);

	return ret;
}

void OBJECT_OT_vertex_group_sort(wmOperatorType *ot)
{
	ot->name= "Sort Vertex Groups";
	ot->idname= "OBJECT_OT_vertex_group_sort";
	ot->description= "Sorts vertex groups alphabetically";

	/* api callbacks */
	ot->poll= vertex_group_poll;
	ot->exec= vertex_group_sort_exec;

	/* flags */
	ot->flag= OPTYPE_REGISTER|OPTYPE_UNDO;
}

static int vgroup_move_exec(bContext *C, wmOperator *op)
{
	Object *ob= ED_object_context(C);
	bDeformGroup *def;
	char *name_array;
	int dir= RNA_enum_get(op->ptr, "direction"), ret;

	def = BLI_findlink(&ob->defbase, ob->actdef - 1);
	if (!def) {
		return OPERATOR_CANCELLED;
	}

	name_array = vgroup_init_remap(ob);

	if (dir == 1) { /*up*/
		void *prev = def->prev;

		BLI_remlink(&ob->defbase, def);
		BLI_insertlinkbefore(&ob->defbase, prev, def);
	} else { /*down*/
		void *next = def->next;

		BLI_remlink(&ob->defbase, def);
		BLI_insertlinkafter(&ob->defbase, next, def);
	}

	ret = vgroup_do_remap(ob, name_array, op);

	if (name_array) MEM_freeN(name_array);

	if (ret != OPERATOR_CANCELLED) {
		DAG_id_tag_update(&ob->id, OB_RECALC_DATA);
		WM_event_add_notifier(C, NC_GEOM|ND_DATA, ob);
	}

	return ret;
}

void OBJECT_OT_vertex_group_move(wmOperatorType *ot)
{
	static EnumPropertyItem vgroup_slot_move[] = {
		{1, "UP", 0, "Up", ""},
		{-1, "DOWN", 0, "Down", ""},
		{0, NULL, 0, NULL, NULL}
	};

	/* identifiers */
	ot->name= "Move Vertex Group";
	ot->idname= "OBJECT_OT_vertex_group_move";

	/* api callbacks */
	ot->poll= vertex_group_poll;
	ot->exec= vgroup_move_exec;

	/* flags */
	ot->flag= OPTYPE_REGISTER|OPTYPE_UNDO;

	RNA_def_enum(ot->srna, "direction", vgroup_slot_move, 0, "Direction", "Direction to move, UP or DOWN");
}