1/***
2 * libccd
3 * ---------------------------------
4 * Copyright (c)2010,2011 Daniel Fiser <danfis@danfis.cz>
5 *
6 *
7 * This file is part of libccd.
8 *
9 * Distributed under the OSI-approved BSD License (the "License");
10 * see accompanying file BDS-LICENSE for details or see
11 * <http://www.opensource.org/licenses/bsd-license.php>.
12 *
13 * This software is distributed WITHOUT ANY WARRANTY; without even the
14 * implied warranty of MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.
15 * See the License for more information.
16 */
17
18#ifndef __CCD_H__
19#define __CCD_H__
20
21#include <ccd/vec3.h>
22
23#ifdef __cplusplus
24extern "C" {
25#endif /* __cplusplus */
26
27/**
28 * Type of *support* function that takes pointer to 3D object and direction
29 * and returns (via vec argument) furthest point from object in specified
30 * direction.
31 */
32typedef void (*ccd_support_fn)(const void *obj, const ccd_vec3_t *dir,
33 ccd_vec3_t *vec);
34
35/**
36 * Returns (via dir argument) first direction vector that will be used in
37 * initialization of algorithm.
38 */
39typedef void (*ccd_first_dir_fn)(const void *obj1, const void *obj2,
40 ccd_vec3_t *dir);
41
42
43/**
44 * Returns (via center argument) geometric center (some point near center)
45 * of given object.
46 */
47typedef void (*ccd_center_fn)(const void *obj1, ccd_vec3_t *center);
48
49/**
50 * Main structure of CCD algorithm.
51 */
52struct _ccd_t {
53 ccd_first_dir_fn first_dir; //!< Returns initial direction where first
54 //!< support point will be searched
55 ccd_support_fn support1; //!< Function that returns support point of
56 //!< first object
57 ccd_support_fn support2; //!< Function that returns support point of
58 //!< second object
59
60 ccd_center_fn center1; //!< Function that returns geometric center of
61 //!< first object
62 ccd_center_fn center2; //!< Function that returns geometric center of
63 //!< second object
64
65 unsigned long max_iterations; //!< Maximal number of iterations
66 ccd_real_t epa_tolerance;
67 ccd_real_t mpr_tolerance; //!< Boundary tolerance for MPR algorithm
68 ccd_real_t dist_tolerance;
69};
70typedef struct _ccd_t ccd_t;
71
72/**
73 * Default first direction.
74 */
75CCD_EXPORT void ccdFirstDirDefault(const void *o1, const void *o2,
76 ccd_vec3_t *dir);
77
78#define CCD_INIT(ccd) \
79 do { \
80 (ccd)->first_dir = ccdFirstDirDefault; \
81 (ccd)->support1 = NULL; \
82 (ccd)->support2 = NULL; \
83 (ccd)->center1 = NULL; \
84 (ccd)->center2 = NULL; \
85 \
86 (ccd)->max_iterations = (unsigned long)-1; \
87 (ccd)->epa_tolerance = CCD_REAL(0.0001); \
88 (ccd)->mpr_tolerance = CCD_REAL(0.0001); \
89 (ccd)->dist_tolerance = CCD_REAL(1E-6); \
90 } while(0)
91
92
93/**
94 * Returns true if two given objects interest.
95 */
96CCD_EXPORT int ccdGJKIntersect(const void *obj1, const void *obj2,
97 const ccd_t *ccd);
98
99/**
100 * This function computes separation vector of two objects. Separation
101 * vector is minimal translation of obj2 to get obj1 and obj2 speparated
102 * (without intersection).
103 * Returns 0 if obj1 and obj2 intersect and sep is filled with translation
104 * vector. If obj1 and obj2 don't intersect -1 is returned.
105 * If memory allocation fails -2 is returned.
106 */
107CCD_EXPORT int ccdGJKSeparate(const void *obj1, const void *obj2,
108 const ccd_t *ccd, ccd_vec3_t *sep);
109
110/**
111 * Computes penetration of obj2 into obj1.
112 * Depth of penetration, direction and position is returned. It means that
113 * if obj2 is translated by distance depth in direction dir objects will
114 * have touching contact, pos should be position in global coordinates
115 * where force should take a place.
116 *
117 * CCD+EPA algorithm is used.
118 *
119 * Returns 0 if obj1 and obj2 intersect and depth, dir and pos are filled
120 * if given non-NULL pointers.
121 * If obj1 and obj2 don't intersect -1 is returned.
122 * If memory allocation fails -2 is returned.
123 */
124CCD_EXPORT int ccdGJKPenetration(const void *obj1, const void *obj2,
125 const ccd_t *ccd, ccd_real_t *depth,
126 ccd_vec3_t *dir, ccd_vec3_t *pos);
127
128/**
129 * Returns true if two given objects intersect - MPR algorithm is used.
130 */
131CCD_EXPORT int ccdMPRIntersect(const void *obj1, const void *obj2,
132 const ccd_t *ccd);
133
134/**
135 * Computes penetration of obj2 into obj1.
136 * Depth of penetration, direction and position is returned, i.e. if obj2
137 * is translated by computed depth in resulting direction obj1 and obj2
138 * would have touching contact. Position is point in global coordinates
139 * where force should take a place.
140 *
141 * Minkowski Portal Refinement algorithm is used (MPR, a.k.a. XenoCollide,
142 * see Game Programming Gem 7).
143 *
144 * Returns 0 if obj1 and obj2 intersect, otherwise -1 is returned.
145 */
146CCD_EXPORT int ccdMPRPenetration(const void *obj1, const void *obj2,
147 const ccd_t *ccd, ccd_real_t *depth,
148 ccd_vec3_t *dir, ccd_vec3_t *pos);
149
150#ifdef __cplusplus
151} /* extern "C" */
152#endif /* __cplusplus */
153
154#endif /* __CCD_H__ */