== SoC Bullet - Bullet Upgrade to 2.76 ==
[blender.git] / extern / bullet2 / BulletDynamics / ConstraintSolver / btPoint2PointConstraint.cpp
1 /*
2 Bullet Continuous Collision Detection and Physics Library
3 Copyright (c) 2003-2006 Erwin Coumans  http://continuousphysics.com/Bullet/
4
5 This software is provided 'as-is', without any express or implied warranty.
6 In no event will the authors be held liable for any damages arising from the use of this software.
7 Permission is granted to anyone to use this software for any purpose, 
8 including commercial applications, and to alter it and redistribute it freely, 
9 subject to the following restrictions:
10
11 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.
12 2. Altered source versions must be plainly marked as such, and must not be misrepresented as being the original software.
13 3. This notice may not be removed or altered from any source distribution.
14 */
15
16
17 #include "btPoint2PointConstraint.h"
18 #include "BulletDynamics/Dynamics/btRigidBody.h"
19 #include <new>
20
21
22
23
24
25 btPoint2PointConstraint::btPoint2PointConstraint(btRigidBody& rbA,btRigidBody& rbB, const btVector3& pivotInA,const btVector3& pivotInB)
26 :btTypedConstraint(POINT2POINT_CONSTRAINT_TYPE,rbA,rbB),m_pivotInA(pivotInA),m_pivotInB(pivotInB),
27 m_flags(0),
28 m_useSolveConstraintObsolete(false)
29 {
30
31 }
32
33
34 btPoint2PointConstraint::btPoint2PointConstraint(btRigidBody& rbA,const btVector3& pivotInA)
35 :btTypedConstraint(POINT2POINT_CONSTRAINT_TYPE,rbA),m_pivotInA(pivotInA),m_pivotInB(rbA.getCenterOfMassTransform()(pivotInA)),
36 m_flags(0),
37 m_useSolveConstraintObsolete(false)
38 {
39         
40 }
41
42 void    btPoint2PointConstraint::buildJacobian()
43 {
44
45         ///we need it for both methods
46         {
47                 m_appliedImpulse = btScalar(0.);
48
49                 btVector3       normal(0,0,0);
50
51                 for (int i=0;i<3;i++)
52                 {
53                         normal[i] = 1;
54                         new (&m_jac[i]) btJacobianEntry(
55                         m_rbA.getCenterOfMassTransform().getBasis().transpose(),
56                         m_rbB.getCenterOfMassTransform().getBasis().transpose(),
57                         m_rbA.getCenterOfMassTransform()*m_pivotInA - m_rbA.getCenterOfMassPosition(),
58                         m_rbB.getCenterOfMassTransform()*m_pivotInB - m_rbB.getCenterOfMassPosition(),
59                         normal,
60                         m_rbA.getInvInertiaDiagLocal(),
61                         m_rbA.getInvMass(),
62                         m_rbB.getInvInertiaDiagLocal(),
63                         m_rbB.getInvMass());
64                 normal[i] = 0;
65                 }
66         }
67
68
69 }
70
71 void btPoint2PointConstraint::getInfo1 (btConstraintInfo1* info)
72 {
73         getInfo1NonVirtual(info);
74 }
75
76 void btPoint2PointConstraint::getInfo1NonVirtual (btConstraintInfo1* info)
77 {
78         if (m_useSolveConstraintObsolete)
79         {
80                 info->m_numConstraintRows = 0;
81                 info->nub = 0;
82         } else
83         {
84                 info->m_numConstraintRows = 3;
85                 info->nub = 3;
86         }
87 }
88
89
90
91
92 void btPoint2PointConstraint::getInfo2 (btConstraintInfo2* info)
93 {
94         getInfo2NonVirtual(info, m_rbA.getCenterOfMassTransform(),m_rbB.getCenterOfMassTransform());
95 }
96
97 void btPoint2PointConstraint::getInfo2NonVirtual (btConstraintInfo2* info, const btTransform& body0_trans, const btTransform& body1_trans)
98 {
99         btAssert(!m_useSolveConstraintObsolete);
100
101          //retrieve matrices
102
103         // anchor points in global coordinates with respect to body PORs.
104    
105     // set jacobian
106     info->m_J1linearAxis[0] = 1;
107         info->m_J1linearAxis[info->rowskip+1] = 1;
108         info->m_J1linearAxis[2*info->rowskip+2] = 1;
109
110         btVector3 a1 = body0_trans.getBasis()*getPivotInA();
111         {
112                 btVector3* angular0 = (btVector3*)(info->m_J1angularAxis);
113                 btVector3* angular1 = (btVector3*)(info->m_J1angularAxis+info->rowskip);
114                 btVector3* angular2 = (btVector3*)(info->m_J1angularAxis+2*info->rowskip);
115                 btVector3 a1neg = -a1;
116                 a1neg.getSkewSymmetricMatrix(angular0,angular1,angular2);
117         }
118     
119         /*info->m_J2linearAxis[0] = -1;
120     info->m_J2linearAxis[s+1] = -1;
121     info->m_J2linearAxis[2*s+2] = -1;
122         */
123         
124         btVector3 a2 = body1_trans.getBasis()*getPivotInB();
125    
126         {
127                 btVector3 a2n = -a2;
128                 btVector3* angular0 = (btVector3*)(info->m_J2angularAxis);
129                 btVector3* angular1 = (btVector3*)(info->m_J2angularAxis+info->rowskip);
130                 btVector3* angular2 = (btVector3*)(info->m_J2angularAxis+2*info->rowskip);
131                 a2.getSkewSymmetricMatrix(angular0,angular1,angular2);
132         }
133     
134
135
136     // set right hand side
137         btScalar currERP = (m_flags & BT_P2P_FLAGS_ERP) ? m_erp : info->erp;
138     btScalar k = info->fps * currERP;
139     int j;
140         for (j=0; j<3; j++)
141     {
142         info->m_constraintError[j*info->rowskip] = k * (a2[j] + body1_trans.getOrigin()[j] - a1[j] - body0_trans.getOrigin()[j]);
143                 //printf("info->m_constraintError[%d]=%f\n",j,info->m_constraintError[j]);
144     }
145         if(m_flags & BT_P2P_FLAGS_CFM)
146         {
147                 for (j=0; j<3; j++)
148                 {
149                         info->cfm[j*info->rowskip] = m_cfm;
150                 }
151         }
152
153         btScalar impulseClamp = m_setting.m_impulseClamp;//
154         for (j=0; j<3; j++)
155     {
156                 if (m_setting.m_impulseClamp > 0)
157                 {
158                         info->m_lowerLimit[j*info->rowskip] = -impulseClamp;
159                         info->m_upperLimit[j*info->rowskip] = impulseClamp;
160                 }
161         }
162         
163 }
164
165
166
167 void    btPoint2PointConstraint::updateRHS(btScalar     timeStep)
168 {
169         (void)timeStep;
170
171 }
172
173 ///override the default global value of a parameter (such as ERP or CFM), optionally provide the axis (0..5). 
174 ///If no axis is provided, it uses the default axis for this constraint.
175 void btPoint2PointConstraint::setParam(int num, btScalar value, int axis)
176 {
177         if(axis != -1)
178         {
179                 btAssertConstrParams(0);
180         }
181         else
182         {
183                 switch(num)
184                 {
185                         case BT_CONSTRAINT_ERP :
186                         case BT_CONSTRAINT_STOP_ERP :
187                                 m_erp = value; 
188                                 m_flags |= BT_P2P_FLAGS_ERP;
189                                 break;
190                         case BT_CONSTRAINT_CFM :
191                         case BT_CONSTRAINT_STOP_CFM :
192                                 m_cfm = value; 
193                                 m_flags |= BT_P2P_FLAGS_CFM;
194                                 break;
195                         default: 
196                                 btAssertConstrParams(0);
197                 }
198         }
199 }
200
201 ///return the local value of parameter
202 btScalar btPoint2PointConstraint::getParam(int num, int axis) const 
203 {
204         btScalar retVal(SIMD_INFINITY);
205         if(axis != -1)
206         {
207                 btAssertConstrParams(0);
208         }
209         else
210         {
211                 switch(num)
212                 {
213                         case BT_CONSTRAINT_ERP :
214                         case BT_CONSTRAINT_STOP_ERP :
215                                 btAssertConstrParams(m_flags & BT_P2P_FLAGS_ERP);
216                                 retVal = m_erp; 
217                                 break;
218                         case BT_CONSTRAINT_CFM :
219                         case BT_CONSTRAINT_STOP_CFM :
220                                 btAssertConstrParams(m_flags & BT_P2P_FLAGS_CFM);
221                                 retVal = m_cfm; 
222                                 break;
223                         default: 
224                                 btAssertConstrParams(0);
225                 }
226         }
227         return retVal;
228 }
229