/**
 * lattice.c
 *
 *
 * $Id$
 *
 * ***** 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., 59 Temple Place - Suite 330, Boston, MA  02111-1307, 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 *****
 */


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

#include "MEM_guardedalloc.h"

#include "BLI_blenlib.h"
#include "BLI_arithb.h"

#include "DNA_armature_types.h"
#include "DNA_mesh_types.h"
#include "DNA_meshdata_types.h"
#include "DNA_modifier_types.h"
#include "DNA_object_types.h"
#include "DNA_scene_types.h"
#include "DNA_lattice_types.h"
#include "DNA_curve_types.h"
#include "DNA_key_types.h"

#include "BKE_anim.h"
#include "BKE_armature.h"
#include "BKE_curve.h"
#include "BKE_cdderivedmesh.h"
#include "BKE_DerivedMesh.h"
#include "BKE_deform.h"
#include "BKE_displist.h"
#include "BKE_global.h"
#include "BKE_key.h"
#include "BKE_lattice.h"
#include "BKE_library.h"
#include "BKE_main.h"
#include "BKE_mesh.h"
#include "BKE_modifier.h"
#include "BKE_object.h"
#include "BKE_screen.h"
#include "BKE_utildefines.h"

//XXX #include "BIF_editdeform.h"

void calc_lat_fudu(int flag, int res, float *fu, float *du)
{
	if(res==1) {
		*fu= 0.0;
		*du= 0.0;
	}
	else if(flag & LT_GRID) {
		*fu= -0.5f*(res-1);
		*du= 1.0f;
	}
	else {
		*fu= -1.0f;
		*du= 2.0f/(res-1);
	}
}

void resizelattice(Lattice *lt, int uNew, int vNew, int wNew, Object *ltOb)
{
	BPoint *bp;
	int i, u, v, w;
	float fu, fv, fw, uc, vc, wc, du=0.0, dv=0.0, dw=0.0;
	float *co, (*vertexCos)[3] = NULL;
	
	/* vertex weight groups are just freed all for now */
	if(lt->dvert) {
		free_dverts(lt->dvert, lt->pntsu*lt->pntsv*lt->pntsw);
		lt->dvert= NULL;
	}
	
	while(uNew*vNew*wNew > 32000) {
		if( uNew>=vNew && uNew>=wNew) uNew--;
		else if( vNew>=uNew && vNew>=wNew) vNew--;
		else wNew--;
	}

	vertexCos = MEM_mallocN(sizeof(*vertexCos)*uNew*vNew*wNew, "tmp_vcos");

	calc_lat_fudu(lt->flag, uNew, &fu, &du);
	calc_lat_fudu(lt->flag, vNew, &fv, &dv);
	calc_lat_fudu(lt->flag, wNew, &fw, &dw);

		/* If old size is different then resolution changed in interface,
		 * try to do clever reinit of points. Pretty simply idea, we just
		 * deform new verts by old lattice, but scaling them to match old
		 * size first.
		 */
	if (ltOb) {
		if (uNew!=1 && lt->pntsu!=1) {
			fu = lt->fu;
			du = (lt->pntsu-1)*lt->du/(uNew-1);
		}

		if (vNew!=1 && lt->pntsv!=1) {
			fv = lt->fv;
			dv = (lt->pntsv-1)*lt->dv/(vNew-1);
		}

		if (wNew!=1 && lt->pntsw!=1) {
			fw = lt->fw;
			dw = (lt->pntsw-1)*lt->dw/(wNew-1);
		}
	}

	co = vertexCos[0];
	for(w=0,wc=fw; w<wNew; w++,wc+=dw) {
		for(v=0,vc=fv; v<vNew; v++,vc+=dv) {
			for(u=0,uc=fu; u<uNew; u++,co+=3,uc+=du) {
				co[0] = uc;
				co[1] = vc;
				co[2] = wc;
			}
		}
	}
	
	if (ltOb) {
		float mat[4][4];
		int typeu = lt->typeu, typev = lt->typev, typew = lt->typew;

			/* works best if we force to linear type (endpoints match) */
		lt->typeu = lt->typev = lt->typew = KEY_LINEAR;

			/* prevent using deformed locations */
		freedisplist(&ltOb->disp);

		Mat4CpyMat4(mat, ltOb->obmat);
		Mat4One(ltOb->obmat);
		lattice_deform_verts(ltOb, NULL, NULL, vertexCos, uNew*vNew*wNew, NULL);
		Mat4CpyMat4(ltOb->obmat, mat);

		lt->typeu = typeu;
		lt->typev = typev;
		lt->typew = typew;
	}

	lt->fu = fu;
	lt->fv = fv;
	lt->fw = fw;
	lt->du = du;
	lt->dv = dv;
	lt->dw = dw;

	lt->pntsu = uNew;
	lt->pntsv = vNew;
	lt->pntsw = wNew;

	MEM_freeN(lt->def);
	lt->def= MEM_callocN(lt->pntsu*lt->pntsv*lt->pntsw*sizeof(BPoint), "lattice bp");
	
	bp= lt->def;
	
	for (i=0; i<lt->pntsu*lt->pntsv*lt->pntsw; i++,bp++) {
		VECCOPY(bp->vec, vertexCos[i]);
	}

	MEM_freeN(vertexCos);
}

Lattice *add_lattice(char *name)
{
	Lattice *lt;
	
	lt= alloc_libblock(&G.main->latt, ID_LT, name);
	
	lt->flag= LT_GRID;
	
	lt->typeu= lt->typev= lt->typew= KEY_BSPLINE;
	
	lt->def= MEM_callocN(sizeof(BPoint), "lattvert"); /* temporary */
	resizelattice(lt, 2, 2, 2, NULL);	/* creates a uniform lattice */
		
	return lt;
}

Lattice *copy_lattice(Lattice *lt)
{
	Lattice *ltn;

	ltn= copy_libblock(lt);
	ltn->def= MEM_dupallocN(lt->def);
		
#if 0 // XXX old animation system
	id_us_plus((ID *)ltn->ipo);
#endif // XXX old animation system

	ltn->key= copy_key(ltn->key);
	if(ltn->key) ltn->key->from= (ID *)ltn;
	
	if(lt->dvert) {
		int tot= lt->pntsu*lt->pntsv*lt->pntsw;
		ltn->dvert = MEM_mallocN (sizeof (MDeformVert)*tot, "Lattice MDeformVert");
		copy_dverts(ltn->dvert, lt->dvert, tot);
	}
	
	return ltn;
}

void free_lattice(Lattice *lt)
{
	if(lt->def) MEM_freeN(lt->def);
	if(lt->dvert) free_dverts(lt->dvert, lt->pntsu*lt->pntsv*lt->pntsw);
	if(lt->editlatt) {
		if(lt->editlatt->def) MEM_freeN(lt->editlatt->def);
		if(lt->editlatt->dvert) free_dverts(lt->editlatt->dvert, lt->pntsu*lt->pntsv*lt->pntsw);
		MEM_freeN(lt->editlatt);
	}
}


void make_local_lattice(Lattice *lt)
{
	Object *ob;
	Lattice *ltn;
	int local=0, lib=0;

	/* - only lib users: do nothing
	 * - only local users: set flag
	 * - mixed: make copy
	 */
	
	if(lt->id.lib==0) return;
	if(lt->id.us==1) {
		lt->id.lib= 0;
		lt->id.flag= LIB_LOCAL;
		new_id(0, (ID *)lt, 0);
		return;
	}
	
	ob= G.main->object.first;
	while(ob) {
		if(ob->data==lt) {
			if(ob->id.lib) lib= 1;
			else local= 1;
		}
		ob= ob->id.next;
	}
	
	if(local && lib==0) {
		lt->id.lib= 0;
		lt->id.flag= LIB_LOCAL;
		new_id(0, (ID *)lt, 0);
	}
	else if(local && lib) {
		ltn= copy_lattice(lt);
		ltn->id.us= 0;
		
		ob= G.main->object.first;
		while(ob) {
			if(ob->data==lt) {
				
				if(ob->id.lib==0) {
					ob->data= ltn;
					ltn->id.us++;
					lt->id.us--;
				}
			}
			ob= ob->id.next;
		}
	}
}

void init_latt_deform(Object *oblatt, Object *ob)
{
		/* we make an array with all differences */
	Lattice *lt= oblatt->data;
	BPoint *bp;
	DispList *dl = find_displist(&oblatt->disp, DL_VERTS);
	float *co = dl?dl->verts:NULL;
	float *fp, imat[4][4];
	float fu, fv, fw;
	int u, v, w;

	if(lt->editlatt) lt= lt->editlatt;
	bp = lt->def;
	
	fp= lt->latticedata= MEM_mallocN(sizeof(float)*3*lt->pntsu*lt->pntsv*lt->pntsw, "latticedata");
	
		/* for example with a particle system: ob==0 */
	if(ob==NULL) {
		/* in deformspace, calc matrix  */
		Mat4Invert(lt->latmat, oblatt->obmat);
	
		/* back: put in deform array */
		Mat4Invert(imat, lt->latmat);
	}
	else {
		/* in deformspace, calc matrix */
		Mat4Invert(imat, oblatt->obmat);
		Mat4MulMat4(lt->latmat, ob->obmat, imat);
	
		/* back: put in deform array */
		Mat4Invert(imat, lt->latmat);
	}
	
	for(w=0,fw=lt->fw; w<lt->pntsw; w++,fw+=lt->dw) {
		for(v=0,fv=lt->fv; v<lt->pntsv; v++, fv+=lt->dv) {
			for(u=0,fu=lt->fu; u<lt->pntsu; u++, bp++, co+=3, fp+=3, fu+=lt->du) {
				if (dl) {
					fp[0] = co[0] - fu;
					fp[1] = co[1] - fv;
					fp[2] = co[2] - fw;
				} else {
					fp[0] = bp->vec[0] - fu;
					fp[1] = bp->vec[1] - fv;
					fp[2] = bp->vec[2] - fw;
				}

				Mat4Mul3Vecfl(imat, fp);
			}
		}
	}
}

void calc_latt_deform(Object *ob, float *co, float weight)
{
	Lattice *lt= ob->data;
	float u, v, w, tu[4], tv[4], tw[4];
	float *fpw, *fpv, *fpu, vec[3];
	int ui, vi, wi, uu, vv, ww;
	
	if(lt->editlatt) lt= lt->editlatt;
	if(lt->latticedata==NULL) return;
	
	/* co is in local coords, treat with latmat */
	
	VECCOPY(vec, co);
	Mat4MulVecfl(lt->latmat, vec);
	
	/* u v w coords */
	
	if(lt->pntsu>1) {
		u= (vec[0]-lt->fu)/lt->du;
		ui= (int)floor(u);
		u -= ui;
		key_curve_position_weights(u, tu, lt->typeu);
	}
	else {
		tu[0]= tu[2]= tu[3]= 0.0; tu[1]= 1.0;
		ui= 0;
	}
	
	if(lt->pntsv>1) {
		v= (vec[1]-lt->fv)/lt->dv;
		vi= (int)floor(v);
		v -= vi;
		key_curve_position_weights(v, tv, lt->typev);
	}
	else {
		tv[0]= tv[2]= tv[3]= 0.0; tv[1]= 1.0;
		vi= 0;
	}
	
	if(lt->pntsw>1) {
		w= (vec[2]-lt->fw)/lt->dw;
		wi= (int)floor(w);
		w -= wi;
		key_curve_position_weights(w, tw, lt->typew);
	}
	else {
		tw[0]= tw[2]= tw[3]= 0.0; tw[1]= 1.0;
		wi= 0;
	}
	
	for(ww= wi-1; ww<=wi+2; ww++) {
		w= tw[ww-wi+1];
		
		if(w!=0.0) {
			if(ww>0) {
				if(ww<lt->pntsw) fpw= lt->latticedata + 3*ww*lt->pntsu*lt->pntsv;
				else fpw= lt->latticedata + 3*(lt->pntsw-1)*lt->pntsu*lt->pntsv;
			}
			else fpw= lt->latticedata;
			
			for(vv= vi-1; vv<=vi+2; vv++) {
				v= w*tv[vv-vi+1];
				
				if(v!=0.0) {
					if(vv>0) {
						if(vv<lt->pntsv) fpv= fpw + 3*vv*lt->pntsu;
						else fpv= fpw + 3*(lt->pntsv-1)*lt->pntsu;
					}
					else fpv= fpw;
					
					for(uu= ui-1; uu<=ui+2; uu++) {
						u= weight*v*tu[uu-ui+1];
						
						if(u!=0.0) {
							if(uu>0) {
								if(uu<lt->pntsu) fpu= fpv + 3*uu;
								else fpu= fpv + 3*(lt->pntsu-1);
							}
							else fpu= fpv;
							
							co[0]+= u*fpu[0];
							co[1]+= u*fpu[1];
							co[2]+= u*fpu[2];
						}
					}
				}
			}
		}
	}
}

void end_latt_deform(Object *ob)
{
	Lattice *lt= ob->data;
	
	if(lt->editlatt) lt= lt->editlatt;
	
	if(lt->latticedata)
		MEM_freeN(lt->latticedata);
	lt->latticedata= NULL;
}

	/* calculations is in local space of deformed object
	   so we store in latmat transform from path coord inside object 
	 */
typedef struct {
	float dmin[3], dmax[3], dsize, dloc[3];
	float curvespace[4][4], objectspace[4][4], objectspace3[3][3];
	int no_rot_axis;
} CurveDeform;

static void init_curve_deform(Object *par, Object *ob, CurveDeform *cd, int dloc)
{
	Mat4Invert(ob->imat, ob->obmat);
	Mat4MulMat4(cd->objectspace, par->obmat, ob->imat);
	Mat4Invert(cd->curvespace, cd->objectspace);
	Mat3CpyMat4(cd->objectspace3, cd->objectspace);
	
	// offset vector for 'no smear'
	if(dloc) {
		Mat4Invert(par->imat, par->obmat);
		VecMat4MulVecfl(cd->dloc, par->imat, ob->obmat[3]);
	}
	else cd->dloc[0]=cd->dloc[1]=cd->dloc[2]= 0.0f;
	
	cd->no_rot_axis= 0;
}

/* this makes sure we can extend for non-cyclic. *vec needs 4 items! */
static int where_on_path_deform(Object *ob, float ctime, float *vec, float *dir, float *quat, float *radius)	/* returns OK */
{
	Curve *cu= ob->data;
	BevList *bl;
	float ctime1;
	int cycl=0;
	
	/* test for cyclic */
	bl= cu->bev.first;
	if (!bl->nr) return 0;
	if(bl && bl->poly> -1) cycl= 1;

	if(cycl==0) {
		ctime1= CLAMPIS(ctime, 0.0, 1.0);
	}
	else ctime1= ctime;
	
	/* vec needs 4 items */
	if(where_on_path(ob, ctime1, vec, dir, quat, radius)) {
		
		if(cycl==0) {
			Path *path= cu->path;
			float dvec[3];
			
			if(ctime < 0.0) {
				VecSubf(dvec, path->data[1].vec, path->data[0].vec);
				VecMulf(dvec, ctime*(float)path->len);
				VECADD(vec, vec, dvec);
				if(quat) QUATCOPY(quat, path->data[0].quat);
				if(radius) *radius= path->data[0].radius;
			}
			else if(ctime > 1.0) {
				VecSubf(dvec, path->data[path->len-1].vec, path->data[path->len-2].vec);
				VecMulf(dvec, (ctime-1.0)*(float)path->len);
				VECADD(vec, vec, dvec);
				if(quat) QUATCOPY(quat, path->data[path->len-1].quat);
				if(radius) *radius= path->data[path->len-1].radius;
			}
		}
		return 1;
	}
	return 0;
}

	/* for each point, rotate & translate to curve */
	/* use path, since it has constant distances */
	/* co: local coord, result local too */
	/* returns quaternion for rotation, using cd->no_rot_axis */
	/* axis is using another define!!! */
static int calc_curve_deform(Scene *scene, Object *par, float *co, short axis, CurveDeform *cd, float *quatp)
{
	Curve *cu= par->data;
	float fac, loc[4], dir[3], cent[3], radius;
	short upflag, index;
	
	if(axis==MOD_CURVE_POSX || axis==MOD_CURVE_NEGX) {
		upflag= OB_POSZ;
		cent[0]= 0.0;
		cent[1]= co[1];
		cent[2]= co[2];
		index= 0;
	}
	else if(axis==MOD_CURVE_POSY || axis==MOD_CURVE_NEGY) {
		upflag= OB_POSZ;
		cent[0]= co[0];
		cent[1]= 0.0;
		cent[2]= co[2];
		index= 1;
	}
	else {
		upflag= OB_POSY;
		cent[0]= co[0];
		cent[1]= co[1];
		cent[2]= 0.0;
		index= 2;
	}
	/* to be sure, mostly after file load */
	if(cu->path==NULL) {
		makeDispListCurveTypes(scene, par, 0);
		if(cu->path==NULL) return 0;	// happens on append...
	}
	
	/* options */
	if(ELEM3(axis, OB_NEGX, OB_NEGY, OB_NEGZ)) {
		if(cu->flag & CU_STRETCH)
			fac= (-co[index]-cd->dmax[index])/(cd->dmax[index] - cd->dmin[index]);
		else
			fac= (cd->dloc[index])/(cu->path->totdist) - (co[index]-cd->dmax[index])/(cu->path->totdist);
	}
	else {
		if(cu->flag & CU_STRETCH)
			fac= (co[index]-cd->dmin[index])/(cd->dmax[index] - cd->dmin[index]);
		else
			fac= (cd->dloc[index])/(cu->path->totdist) + (co[index]-cd->dmin[index])/(cu->path->totdist);
	}
	
#if 0 // XXX old animation system
	/* we want the ipo to work on the default 100 frame range, because there's no  
	   actual time involved in path position */
	// huh? by WHY!!!!???? - Aligorith
	if(cu->ipo) {
		fac*= 100.0f;
		if(calc_ipo_spec(cu->ipo, CU_SPEED, &fac)==0)
			fac/= 100.0;
	}
#endif // XXX old animation system
	
	if( where_on_path_deform(par, fac, loc, dir, NULL, &radius)) {	/* returns OK */
		float q[4], mat[3][3], quat[4];
		
		if(cd->no_rot_axis)	/* set by caller */
			dir[cd->no_rot_axis-1]= 0.0f;
		
		/* -1 for compatibility with old track defines */
		vectoquat(dir, axis-1, upflag, quat);
		
		/* the tilt */
		if(loc[3]!=0.0) {
			Normalize(dir);
			q[0]= (float)cos(0.5*loc[3]);
			fac= (float)sin(0.5*loc[3]);
			q[1]= -fac*dir[0];
			q[2]= -fac*dir[1];
			q[3]= -fac*dir[2];
			QuatMul(quat, q, quat);
		}		
		QuatToMat3(quat, mat);

		if(cu->flag & CU_PATH_RADIUS) {
			float tmat[3][3], rmat[3][3];
			Mat3Scale(tmat, radius);
			Mat3MulMat3(rmat, mat, tmat);
			Mat3CpyMat3(mat, rmat);
		}

		/* local rotation */
		Mat3MulVecfl(mat, cent);
		
		/* translation */
		VECADD(co, cent, loc);
		
		if(quatp)
			QUATCOPY(quatp, quat);
		
		return 1;
	}
	return 0;
}

void curve_deform_verts(Scene *scene, Object *cuOb, Object *target, DerivedMesh *dm, float (*vertexCos)[3], int numVerts, char *vgroup, short defaxis)
{
	Curve *cu;
	int a, flag;
	CurveDeform cd;
	int use_vgroups;

	if(cuOb->type != OB_CURVE)
		return;

	cu = cuOb->data;
	flag = cu->flag;
	cu->flag |= (CU_PATH|CU_FOLLOW); // needed for path & bevlist

	init_curve_deform(cuOb, target, &cd, (cu->flag & CU_STRETCH)==0);
		
	/* check whether to use vertex groups (only possible if target is a Mesh)
	 * we want either a Mesh with no derived data, or derived data with
	 * deformverts
	 */
	if(target && target->type==OB_MESH) {
		/* if there's derived data without deformverts, don't use vgroups */
		if(dm && !dm->getVertData(dm, 0, CD_MDEFORMVERT))
			use_vgroups = 0;
		else
			use_vgroups = 1;
	} else
		use_vgroups = 0;
	
	if(vgroup && vgroup[0] && use_vgroups) {
		bDeformGroup *curdef;
		Mesh *me= target->data;
		int index;
		
		/* find the group (weak loop-in-loop) */
		for(index = 0, curdef = target->defbase.first; curdef;
		    curdef = curdef->next, index++)
			if (!strcmp(curdef->name, vgroup))
				break;

		if(curdef && (me->dvert || dm)) {
			MDeformVert *dvert = me->dvert;
			float vec[3];
			int j;

			INIT_MINMAX(cd.dmin, cd.dmax);

			for(a = 0; a < numVerts; a++, dvert++) {
				if(dm) dvert = dm->getVertData(dm, a, CD_MDEFORMVERT);

				for(j = 0; j < dvert->totweight; j++) {
					if(dvert->dw[j].def_nr == index) {
						Mat4MulVecfl(cd.curvespace, vertexCos[a]);
						DO_MINMAX(vertexCos[a], cd.dmin, cd.dmax);
						break;
					}
				}
			}

			dvert = me->dvert;
			for(a = 0; a < numVerts; a++, dvert++) {
				if(dm) dvert = dm->getVertData(dm, a, CD_MDEFORMVERT);

				for(j = 0; j < dvert->totweight; j++) {
					if(dvert->dw[j].def_nr == index) {
						VECCOPY(vec, vertexCos[a]);
						calc_curve_deform(scene, cuOb, vec, defaxis, &cd, NULL);
						VecLerpf(vertexCos[a], vertexCos[a], vec,
						         dvert->dw[j].weight);
						Mat4MulVecfl(cd.objectspace, vertexCos[a]);
						break;
					}
				}
			}
		}
	} else {
		INIT_MINMAX(cd.dmin, cd.dmax);
			
		for(a = 0; a < numVerts; a++) {
			Mat4MulVecfl(cd.curvespace, vertexCos[a]);
			DO_MINMAX(vertexCos[a], cd.dmin, cd.dmax);
		}

		for(a = 0; a < numVerts; a++) {
			calc_curve_deform(scene, cuOb, vertexCos[a], defaxis, &cd, NULL);
			Mat4MulVecfl(cd.objectspace, vertexCos[a]);
		}
	}
	cu->flag = flag;
}

/* input vec and orco = local coord in armature space */
/* orco is original not-animated or deformed reference point */
/* result written in vec and mat */
void curve_deform_vector(Scene *scene, Object *cuOb, Object *target, float *orco, float *vec, float mat[][3], int no_rot_axis)
{
	CurveDeform cd;
	float quat[4];
	
	if(cuOb->type != OB_CURVE) {
		Mat3One(mat);
		return;
	}

	init_curve_deform(cuOb, target, &cd, 0);	/* 0 no dloc */
	cd.no_rot_axis= no_rot_axis;				/* option to only rotate for XY, for example */
	
	VECCOPY(cd.dmin, orco);
	VECCOPY(cd.dmax, orco);

	Mat4MulVecfl(cd.curvespace, vec);
	
	if(calc_curve_deform(scene, cuOb, vec, target->trackflag+1, &cd, quat)) {
		float qmat[3][3];
		
		QuatToMat3(quat, qmat);
		Mat3MulMat3(mat, qmat, cd.objectspace3);
	}
	else
		Mat3One(mat);
	
	Mat4MulVecfl(cd.objectspace, vec);

}

void lattice_deform_verts(Object *laOb, Object *target, DerivedMesh *dm,
                          float (*vertexCos)[3], int numVerts, char *vgroup)
{
	int a;
	int use_vgroups;

	if(laOb->type != OB_LATTICE)
		return;

	init_latt_deform(laOb, target);

	/* check whether to use vertex groups (only possible if target is a Mesh)
	 * we want either a Mesh with no derived data, or derived data with
	 * deformverts
	 */
	if(target && target->type==OB_MESH) {
		/* if there's derived data without deformverts, don't use vgroups */
		if(dm && !dm->getVertData(dm, 0, CD_MDEFORMVERT))
			use_vgroups = 0;
		else
			use_vgroups = 1;
	} else
		use_vgroups = 0;
	
	if(vgroup && vgroup[0] && use_vgroups) {
		bDeformGroup *curdef;
		Mesh *me = target->data;
		int index = 0;
		
		/* find the group (weak loop-in-loop) */
		for(curdef = target->defbase.first; curdef;
		    curdef = curdef->next, index++)
			if(!strcmp(curdef->name, vgroup)) break;

		if(curdef && (me->dvert || dm)) {
			MDeformVert *dvert = me->dvert;
			int j;
			
			for(a = 0; a < numVerts; a++, dvert++) {
				if(dm) dvert = dm->getVertData(dm, a, CD_MDEFORMVERT);
				for(j = 0; j < dvert->totweight; j++) {
					if (dvert->dw[j].def_nr == index) {
						calc_latt_deform(laOb, vertexCos[a], dvert->dw[j].weight);
					}
				}
			}
		}
	} else {
		for(a = 0; a < numVerts; a++) {
			calc_latt_deform(laOb, vertexCos[a], 1.0f);
		}
	}
	end_latt_deform(laOb);
}

int object_deform_mball(Object *ob)
{
	if(ob->parent && ob->parent->type==OB_LATTICE && ob->partype==PARSKEL) {
		DispList *dl;

		for (dl=ob->disp.first; dl; dl=dl->next) {
			lattice_deform_verts(ob->parent, ob, NULL,
			                     (float(*)[3]) dl->verts, dl->nr, NULL);
		}

		return 1;
	} else {
		return 0;
	}
}

static BPoint *latt_bp(Lattice *lt, int u, int v, int w)
{
	return lt->def+ u + v*lt->pntsu + w*lt->pntsu*lt->pntsv;
}

void outside_lattice(Lattice *lt)
{
	BPoint *bp, *bp1, *bp2;
	int u, v, w;
	float fac1, du=0.0, dv=0.0, dw=0.0;

	if(lt->flag & LT_OUTSIDE) {
		bp= lt->def;

		if(lt->pntsu>1) du= 1.0f/((float)lt->pntsu-1);
		if(lt->pntsv>1) dv= 1.0f/((float)lt->pntsv-1);
		if(lt->pntsw>1) dw= 1.0f/((float)lt->pntsw-1);
			
		for(w=0; w<lt->pntsw; w++) {
			
			for(v=0; v<lt->pntsv; v++) {
			
				for(u=0; u<lt->pntsu; u++, bp++) {
					if(u==0 || v==0 || w==0 || u==lt->pntsu-1 || v==lt->pntsv-1 || w==lt->pntsw-1);
					else {
					
						bp->hide= 1;
						bp->f1 &= ~SELECT;
						
						/* u extrema */
						bp1= latt_bp(lt, 0, v, w);
						bp2= latt_bp(lt, lt->pntsu-1, v, w);
						
						fac1= du*u;
						bp->vec[0]= (1.0f-fac1)*bp1->vec[0] + fac1*bp2->vec[0];
						bp->vec[1]= (1.0f-fac1)*bp1->vec[1] + fac1*bp2->vec[1];
						bp->vec[2]= (1.0f-fac1)*bp1->vec[2] + fac1*bp2->vec[2];
						
						/* v extrema */
						bp1= latt_bp(lt, u, 0, w);
						bp2= latt_bp(lt, u, lt->pntsv-1, w);
						
						fac1= dv*v;
						bp->vec[0]+= (1.0f-fac1)*bp1->vec[0] + fac1*bp2->vec[0];
						bp->vec[1]+= (1.0f-fac1)*bp1->vec[1] + fac1*bp2->vec[1];
						bp->vec[2]+= (1.0f-fac1)*bp1->vec[2] + fac1*bp2->vec[2];
						
						/* w extrema */
						bp1= latt_bp(lt, u, v, 0);
						bp2= latt_bp(lt, u, v, lt->pntsw-1);
						
						fac1= dw*w;
						bp->vec[0]+= (1.0f-fac1)*bp1->vec[0] + fac1*bp2->vec[0];
						bp->vec[1]+= (1.0f-fac1)*bp1->vec[1] + fac1*bp2->vec[1];
						bp->vec[2]+= (1.0f-fac1)*bp1->vec[2] + fac1*bp2->vec[2];
						
						VecMulf(bp->vec, 0.3333333f);
						
					}
				}
				
			}
			
		}
	}
	else {
		bp= lt->def;

		for(w=0; w<lt->pntsw; w++)
			for(v=0; v<lt->pntsv; v++)
				for(u=0; u<lt->pntsu; u++, bp++)
					bp->hide= 0;
	}
}

float (*lattice_getVertexCos(struct Object *ob, int *numVerts_r))[3]
{
	Lattice *lt = ob->data;
	int i, numVerts;
	float (*vertexCos)[3];

	if(lt->editlatt) lt= lt->editlatt;
	numVerts = *numVerts_r = lt->pntsu*lt->pntsv*lt->pntsw;
	
	vertexCos = MEM_mallocN(sizeof(*vertexCos)*numVerts,"lt_vcos");
	
	for (i=0; i<numVerts; i++) {
		VECCOPY(vertexCos[i], lt->def[i].vec);
	}

	return vertexCos;
}

void lattice_applyVertexCos(struct Object *ob, float (*vertexCos)[3])
{
	Lattice *lt = ob->data;
	int i, numVerts = lt->pntsu*lt->pntsv*lt->pntsw;

	for (i=0; i<numVerts; i++) {
		VECCOPY(lt->def[i].vec, vertexCos[i]);
	}
}

void lattice_calc_modifiers(Scene *scene, Object *ob)
{
	Lattice *lt= ob->data;
	ModifierData *md = modifiers_getVirtualModifierList(ob);
	float (*vertexCos)[3] = NULL;
	int numVerts, editmode = (lt->editlatt!=NULL);

	freedisplist(&ob->disp);

	if (!editmode) {
		do_ob_key(scene, ob);
	}

	for (; md; md=md->next) {
		ModifierTypeInfo *mti = modifierType_getInfo(md->type);

		md->scene= scene;
		
		if (!(md->mode&eModifierMode_Realtime)) continue;
		if (editmode && !(md->mode&eModifierMode_Editmode)) continue;
		if (mti->isDisabled && mti->isDisabled(md)) continue;
		if (mti->type!=eModifierTypeType_OnlyDeform) continue;

		if (!vertexCos) vertexCos = lattice_getVertexCos(ob, &numVerts);
		mti->deformVerts(md, ob, NULL, vertexCos, numVerts, 0, 0);
	}

	/* always displist to make this work like derivedmesh */
	if (!vertexCos) vertexCos = lattice_getVertexCos(ob, &numVerts);
	
	{
		DispList *dl = MEM_callocN(sizeof(*dl), "lt_dl");
		dl->type = DL_VERTS;
		dl->parts = 1;
		dl->nr = numVerts;
		dl->verts = (float*) vertexCos;
		
		BLI_addtail(&ob->disp, dl);
	}
}

struct MDeformVert* lattice_get_deform_verts(struct Object *oblatt)
{
	if(oblatt->type == OB_LATTICE)
	{
		Lattice *lt = (Lattice*)oblatt->data;
		if(lt->editlatt) lt= lt->editlatt;
		return lt->dvert;
	}

	return NULL;	
}