delaunay.h

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#ifndef DELAUNAY_H
#define DELAUNAY_H
 
/*
**  delaunay.c : compute 2D delaunay triangulation in the plane.
**  Copyright (C) 2005  Wael El Oraiby <wael.eloraiby@gmail.com>
**
**
**  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 3 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, see <http://www.gnu.org/licenses/>.
*/
 
#define DEL_CIRCLE
 
 
 
#ifdef __cplusplus
extern "C" {
#endif
 
/* define the floating point type, comment to use float - Be careful "float" type will assert more often */
#define USE_DOUBLE
 
#define FAST_PREDICATE  1   /* fast but floating point errors are more likely to occur */
#define LOOSE_PREDICATE 2   /* loose with epsilon defined in the delaunay file - errors will happen but less frequently */
#define EXACT_PREDICATE 3   /* use exact arithmetic - slower, but shouldn't produce any floating point error */
 
#define PREDICATE   EXACT_PREDICATE
 
#if PREDICATE == EXACT_PREDICATE && !defined(USE_DOUBLE)
#   define USE_DOUBLE
#endif
 
#ifdef USE_DOUBLE
typedef double real;
#else
typedef float   real;
#endif
 
typedef struct {
    real    x, y;
} del_point2d_t;
 
typedef struct {
    /** input points count */
    quint32 num_points;
 
    /** the input points */
    del_point2d_t*  points;
 
    /** number of returned faces */
    quint32 num_faces;
 
    /** the triangles given as a sequence: num verts, verts indices, num verts, verts indices first face is the external face */
    quint32*    faces;
} delaunay2d_t;
 
typedef int     (*incircle_predicate_t)(del_point2d_t* p0, del_point2d_t* p1, del_point2d_t* p2, del_point2d_t* p3);
 
/*
 * build the 2D Delaunay triangulation given a set of points of at least 3 points
 *
 * @param points point set given as a sequence of tuple x0, y0, x1, y1, ....
 * @param num_points number of given point
 * @return: the number of created faces
 */
delaunay2d_t*           delaunay2d_from(del_point2d_t *points, quint32 num_points);
 
/*
 * release a delaunay2d object
 */
void                delaunay2d_release(delaunay2d_t* del);
 
#ifdef __cplusplus
}
#endif
 
#endif // DELAUNAY_H