1
2 /*
3 -----------------------------------------------------------------------------
4 This source file is part of GIMPACT Library.
5
6 For the latest info, see http://gimpact.sourceforge.net/
7
8 Copyright (c) 2006 Francisco Leon Najera. C.C. 80087371.
9 email: projectileman@yahoo.com
10
11 This library is free software; you can redistribute it and/or
12 modify it under the terms of EITHER:
13 (1) The GNU Lesser General Public License as published by the Free
14 Software Foundation; either version 2.1 of the License, or (at
15 your option) any later version. The text of the GNU Lesser
16 General Public License is included with this library in the
17 file GIMPACT-LICENSE-LGPL.TXT.
18 (2) The BSD-style license that is included with this library in
19 the file GIMPACT-LICENSE-BSD.TXT.
20 (3) The zlib/libpng license that is included with this library in
21 the file GIMPACT-LICENSE-ZLIB.TXT.
22
23 This library is distributed in the hope that it will be useful,
24 but WITHOUT ANY WARRANTY; without even the implied warranty of
25 MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the files
26 GIMPACT-LICENSE-LGPL.TXT, GIMPACT-LICENSE-ZLIB.TXT and GIMPACT-LICENSE-BSD.TXT for more details.
27
28 -----------------------------------------------------------------------------
29 */
30
31 #include "gim_contact.h"
32
33 #define MAX_COINCIDENT 8
34
merge_contacts(const gim_contact_array & contacts,bool normal_contact_average)35 void gim_contact_array::merge_contacts(
36 const gim_contact_array& contacts, bool normal_contact_average)
37 {
38 clear();
39
40 if (contacts.size() == 1)
41 {
42 push_back(contacts.back());
43 return;
44 }
45
46 gim_array<GIM_RSORT_TOKEN> keycontacts(contacts.size());
47 keycontacts.resize(contacts.size(), false);
48
49 //fill key contacts
50
51 GUINT i;
52
53 for (i = 0; i < contacts.size(); i++)
54 {
55 keycontacts[i].m_key = contacts[i].calc_key_contact();
56 keycontacts[i].m_value = i;
57 }
58
59 //sort keys
60 gim_heap_sort(keycontacts.pointer(), keycontacts.size(), GIM_RSORT_TOKEN_COMPARATOR());
61
62 // Merge contacts
63
64 GUINT coincident_count = 0;
65 btVector3 coincident_normals[MAX_COINCIDENT];
66
67 GUINT last_key = keycontacts[0].m_key;
68 GUINT key = 0;
69
70 push_back(contacts[keycontacts[0].m_value]);
71 GIM_CONTACT* pcontact = &back();
72
73 for (i = 1; i < keycontacts.size(); i++)
74 {
75 key = keycontacts[i].m_key;
76 const GIM_CONTACT* scontact = &contacts[keycontacts[i].m_value];
77
78 if (last_key == key) //same points
79 {
80 //merge contact
81 if (pcontact->m_depth - CONTACT_DIFF_EPSILON > scontact->m_depth) //)
82 {
83 *pcontact = *scontact;
84 coincident_count = 0;
85 }
86 else if (normal_contact_average)
87 {
88 if (btFabs(pcontact->m_depth - scontact->m_depth) < CONTACT_DIFF_EPSILON)
89 {
90 if (coincident_count < MAX_COINCIDENT)
91 {
92 coincident_normals[coincident_count] = scontact->m_normal;
93 coincident_count++;
94 }
95 }
96 }
97 }
98 else
99 { //add new contact
100
101 if (normal_contact_average && coincident_count > 0)
102 {
103 pcontact->interpolate_normals(coincident_normals, coincident_count);
104 coincident_count = 0;
105 }
106
107 push_back(*scontact);
108 pcontact = &back();
109 }
110 last_key = key;
111 }
112 }
113
merge_contacts_unique(const gim_contact_array & contacts)114 void gim_contact_array::merge_contacts_unique(const gim_contact_array& contacts)
115 {
116 clear();
117
118 if (contacts.size() == 1)
119 {
120 push_back(contacts.back());
121 return;
122 }
123
124 GIM_CONTACT average_contact = contacts.back();
125
126 for (GUINT i = 1; i < contacts.size(); i++)
127 {
128 average_contact.m_point += contacts[i].m_point;
129 average_contact.m_normal += contacts[i].m_normal * contacts[i].m_depth;
130 }
131
132 //divide
133 GREAL divide_average = 1.0f / ((GREAL)contacts.size());
134
135 average_contact.m_point *= divide_average;
136
137 average_contact.m_normal *= divide_average;
138
139 average_contact.m_depth = average_contact.m_normal.length();
140
141 average_contact.m_normal /= average_contact.m_depth;
142 }
143