1
2 /*
3 This source file is part of GIMPACT Library.
4
5 For the latest info, see http://gimpact.sourceforge.net/
6
7 Copyright (c) 2007 Francisco Leon Najera. C.C. 80087371.
8 email: projectileman@yahoo.com
9
10
11 This software is provided 'as-is', without any express or implied warranty.
12 In no event will the authors be held liable for any damages arising from the use of this software.
13 Permission is granted to anyone to use this software for any purpose,
14 including commercial applications, and to alter it and redistribute it freely,
15 subject to the following restrictions:
16
17 1. The origin of this software must not be misrepresented; you must not claim that you wrote the original software. If you use this software in a product, an acknowledgment in the product documentation would be appreciated but is not required.
18 2. Altered source versions must be plainly marked as such, and must not be misrepresented as being the original software.
19 3. This notice may not be removed or altered from any source distribution.
20 */
21 #include "btContactProcessing.h"
22
23 #define MAX_COINCIDENT 8
24
25 struct CONTACT_KEY_TOKEN
26 {
27 unsigned int m_key;
28 int m_value;
CONTACT_KEY_TOKENCONTACT_KEY_TOKEN29 CONTACT_KEY_TOKEN()
30 {
31 }
32
CONTACT_KEY_TOKENCONTACT_KEY_TOKEN33 CONTACT_KEY_TOKEN(unsigned int key,int token)
34 {
35 m_key = key;
36 m_value = token;
37 }
38
CONTACT_KEY_TOKENCONTACT_KEY_TOKEN39 CONTACT_KEY_TOKEN(const CONTACT_KEY_TOKEN& rtoken)
40 {
41 m_key = rtoken.m_key;
42 m_value = rtoken.m_value;
43 }
44
operator <CONTACT_KEY_TOKEN45 inline bool operator <(const CONTACT_KEY_TOKEN& other) const
46 {
47 return (m_key < other.m_key);
48 }
49
operator >CONTACT_KEY_TOKEN50 inline bool operator >(const CONTACT_KEY_TOKEN& other) const
51 {
52 return (m_key > other.m_key);
53 }
54
55 };
56
57 class CONTACT_KEY_TOKEN_COMP
58 {
59 public:
60
operator ()(const CONTACT_KEY_TOKEN & a,const CONTACT_KEY_TOKEN & b) const61 bool operator() ( const CONTACT_KEY_TOKEN& a, const CONTACT_KEY_TOKEN& b ) const
62 {
63 return ( a < b );
64 }
65 };
66
67
merge_contacts(const btContactArray & contacts,bool normal_contact_average)68 void btContactArray::merge_contacts(
69 const btContactArray & contacts, bool normal_contact_average)
70 {
71 clear();
72
73 int i;
74 if(contacts.size()==0) return;
75
76
77 if(contacts.size()==1)
78 {
79 push_back(contacts[0]);
80 return;
81 }
82
83 btAlignedObjectArray<CONTACT_KEY_TOKEN> keycontacts;
84
85 keycontacts.reserve(contacts.size());
86
87 //fill key contacts
88
89 for ( i = 0;i<contacts.size() ;i++ )
90 {
91 keycontacts.push_back(CONTACT_KEY_TOKEN(contacts[i].calc_key_contact(),i));
92 }
93
94 //sort keys
95 keycontacts.quickSort(CONTACT_KEY_TOKEN_COMP());
96
97 // Merge contacts
98 int coincident_count=0;
99 btVector3 coincident_normals[MAX_COINCIDENT];
100
101 unsigned int last_key = keycontacts[0].m_key;
102 unsigned int key = 0;
103
104 push_back(contacts[keycontacts[0].m_value]);
105
106 GIM_CONTACT * pcontact = &(*this)[0];
107
108 for( i=1;i<keycontacts.size();i++)
109 {
110 key = keycontacts[i].m_key;
111 const GIM_CONTACT * scontact = &contacts[keycontacts[i].m_value];
112
113 if(last_key == key)//same points
114 {
115 //merge contact
116 if(pcontact->m_depth - CONTACT_DIFF_EPSILON > scontact->m_depth)//)
117 {
118 *pcontact = *scontact;
119 coincident_count = 0;
120 }
121 else if(normal_contact_average)
122 {
123 if(btFabs(pcontact->m_depth - scontact->m_depth)<CONTACT_DIFF_EPSILON)
124 {
125 if(coincident_count<MAX_COINCIDENT)
126 {
127 coincident_normals[coincident_count] = scontact->m_normal;
128 coincident_count++;
129 }
130 }
131 }
132 }
133 else
134 {//add new contact
135
136 if(normal_contact_average && coincident_count>0)
137 {
138 pcontact->interpolate_normals(coincident_normals,coincident_count);
139 coincident_count = 0;
140 }
141
142 push_back(*scontact);
143 pcontact = &(*this)[this->size()-1];
144 }
145 last_key = key;
146 }
147 }
148
merge_contacts_unique(const btContactArray & contacts)149 void btContactArray::merge_contacts_unique(const btContactArray & contacts)
150 {
151 clear();
152
153 if(contacts.size()==0) return;
154
155 if(contacts.size()==1)
156 {
157 push_back(contacts[0]);
158 return;
159 }
160
161 GIM_CONTACT average_contact = contacts[0];
162
163 for (int i=1;i<contacts.size() ;i++ )
164 {
165 average_contact.m_point += contacts[i].m_point;
166 average_contact.m_normal += contacts[i].m_normal * contacts[i].m_depth;
167 }
168
169 //divide
170 btScalar divide_average = 1.0f/((btScalar)contacts.size());
171
172 average_contact.m_point *= divide_average;
173
174 average_contact.m_normal *= divide_average;
175
176 average_contact.m_depth = average_contact.m_normal.length();
177
178 average_contact.m_normal /= average_contact.m_depth;
179
180 }
181
182