/*
 * ***** 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.
 *
 * Contributor(s): Joseph Eagar.
 *
 * ***** END GPL LICENSE BLOCK *****
 */

/*
 * BMESH ITERATORS
 * 
 * The functions and structures in this file 
 * provide a unified method for iterating over 
 * the elements of a mesh and answering simple
 * adjacency queries. Tool authors should use
 * the iterators provided in this file instead
 * of inspecting the structure directly.
 *
*/

#ifndef BM_ITERATORS_H
#define BM_ITERATORS_H

#include "BLI_mempool.h"

/* Defines for passing to BMIter_New.
 *
 * "OF" can be substituted for "around"
 * so BM_VERTS_OF_FACE means "vertices
 * around a face."
 */

/* these iterator over all elements of a specific
 * type in the mesh.*/
#define BM_VERTS_OF_MESH 			1
#define BM_EDGES_OF_MESH 			2
#define BM_FACES_OF_MESH 			3

/*these are topological iterators.*/
#define BM_EDGES_OF_VERT 			4
#define BM_FACES_OF_VERT 			5
#define BM_LOOPS_OF_VERT			6
#define BM_FACES_OF_EDGE 			7
#define BM_VERTS_OF_FACE 			8
#define BM_EDGES_OF_FACE 			9
#define BM_LOOPS_OF_FACE 			10
/* returns elements from all boundaries, and returns 
 * the first element at the end to flag that we're entering 
 * a different face hole boundary*/
#define BM_ALL_LOOPS_OF_FACE		11

/* iterate through loops around this loop, which are fetched
 * from the other faces in the radial cycle surrounding the
 * input loop's edge.*/
#define BM_LOOPS_OF_LOOP		12
#define BM_LOOPS_OF_EDGE		13

#define BM_ITER(ele, iter, bm, itype, data)                                   \
	ele = BMIter_New(iter, bm, itype, data);                                  \
	for ( ; ele; ele=BMIter_Step(iter))

#define BM_ITER_INDEX(ele, iter, bm, itype, data, indexvar)                   \
	ele = BMIter_New(iter, bm, itype, data);                                  \
	for (indexvar=0; ele; indexvar++, ele=BMIter_Step(iter))

/*Iterator Structure*/
typedef struct BMIter {
	BLI_mempool_iter pooliter;

	struct BMVert *firstvert, *nextvert, *vdata;
	struct BMEdge *firstedge, *nextedge, *edata;
	struct BMLoop *firstloop, *nextloop, *ldata, *l;
	struct BMFace *firstpoly, *nextpoly, *pdata;
	struct BMesh *bm;
	void (*begin)(struct BMIter *iter);
	void *(*step)(struct BMIter *iter);
	union {
		void       *p;
		int         i;
		long        l;
		float       f;
	} filter;
	int count;
	char itype;
} BMIter;

void *BMIter_AtIndex(struct BMesh *bm, const char htype, void *data, int index);
int   BMIter_AsArray(struct BMesh *bm, const char htype, void *data, void **array, const int len);

/* private for bmesh_iterators_inline.c */
void  bmiter__vert_of_mesh_begin(struct BMIter *iter);
void *bmiter__vert_of_mesh_step(struct BMIter *iter);
void  bmiter__edge_of_mesh_begin(struct BMIter *iter);
void *bmiter__edge_of_mesh_step(struct BMIter *iter);
void  bmiter__face_of_mesh_begin(struct BMIter *iter);
void *bmiter__face_of_mesh_step(struct BMIter *iter);
void  bmiter__edge_of_vert_begin(struct BMIter *iter);
void *bmiter__edge_of_vert_step(struct BMIter *iter);
void  bmiter__face_of_vert_begin(struct BMIter *iter);
void *bmiter__face_of_vert_step(struct BMIter *iter);
void  bmiter__loop_of_vert_begin(struct BMIter *iter);
void *bmiter__loop_of_vert_step(struct BMIter *iter);
void  bmiter__loops_of_edge_begin(struct BMIter *iter);
void *bmiter__loops_of_edge_step(struct BMIter *iter);
void  bmiter__loops_of_loop_begin(struct BMIter *iter);
void *bmiter__loops_of_loop_step(struct BMIter *iter);
void  bmiter__face_of_edge_begin(struct BMIter *iter);
void *bmiter__face_of_edge_step(struct BMIter *iter);
void  bmiter__vert_of_face_begin(struct BMIter *iter);
void *bmiter__vert_of_face_step(struct BMIter *iter);
void  bmiter__edge_of_face_begin(struct BMIter *iter);
void *bmiter__edge_of_face_step(struct BMIter *iter);
void  bmiter__loop_of_face_begin(struct BMIter *iter);
void *bmiter__loop_of_face_step(struct BMIter *iter);

#include "intern/bmesh_iterators_inline.c"

#endif