Bullet Collision Detection & Physics Library
btTypedConstraint.cpp
Go to the documentation of this file.
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 #include "btTypedConstraint.h"
19 
20 #define DEFAULT_DEBUGDRAW_SIZE btScalar(0.05f)
21 
23  : btTypedObject(type),
24  m_userConstraintType(-1),
25  m_userConstraintPtr((void*)-1),
26  m_breakingImpulseThreshold(SIMD_INFINITY),
27  m_isEnabled(true),
28  m_needsFeedback(false),
29  m_overrideNumSolverIterations(-1),
30  m_rbA(rbA),
31  m_rbB(getFixedBody()),
32  m_appliedImpulse(btScalar(0.)),
33  m_dbgDrawSize(DEFAULT_DEBUGDRAW_SIZE),
34  m_jointFeedback(0)
35 {
36 }
37 
39  : btTypedObject(type),
40  m_userConstraintType(-1),
41  m_userConstraintPtr((void*)-1),
42  m_breakingImpulseThreshold(SIMD_INFINITY),
43  m_isEnabled(true),
44  m_needsFeedback(false),
45  m_overrideNumSolverIterations(-1),
46  m_rbA(rbA),
47  m_rbB(rbB),
48  m_appliedImpulse(btScalar(0.)),
49  m_dbgDrawSize(DEFAULT_DEBUGDRAW_SIZE),
50  m_jointFeedback(0)
51 {
52 }
53 
55 {
56  if (lowLim > uppLim)
57  {
58  return btScalar(1.0f);
59  }
60  else if (lowLim == uppLim)
61  {
62  return btScalar(0.0f);
63  }
64  btScalar lim_fact = btScalar(1.0f);
65  btScalar delta_max = vel / timeFact;
66  if (delta_max < btScalar(0.0f))
67  {
68  if ((pos >= lowLim) && (pos < (lowLim - delta_max)))
69  {
70  lim_fact = (lowLim - pos) / delta_max;
71  }
72  else if (pos < lowLim)
73  {
74  lim_fact = btScalar(0.0f);
75  }
76  else
77  {
78  lim_fact = btScalar(1.0f);
79  }
80  }
81  else if (delta_max > btScalar(0.0f))
82  {
83  if ((pos <= uppLim) && (pos > (uppLim - delta_max)))
84  {
85  lim_fact = (uppLim - pos) / delta_max;
86  }
87  else if (pos > uppLim)
88  {
89  lim_fact = btScalar(0.0f);
90  }
91  else
92  {
93  lim_fact = btScalar(1.0f);
94  }
95  }
96  else
97  {
98  lim_fact = btScalar(0.0f);
99  }
100  return lim_fact;
101 }
102 
104 const char* btTypedConstraint::serialize(void* dataBuffer, btSerializer* serializer) const
105 {
107 
108  tcd->m_rbA = (btRigidBodyData*)serializer->getUniquePointer(&m_rbA);
109  tcd->m_rbB = (btRigidBodyData*)serializer->getUniquePointer(&m_rbB);
110  char* name = (char*)serializer->findNameForPointer(this);
111  tcd->m_name = (char*)serializer->getUniquePointer(name);
112  if (tcd->m_name)
113  {
114  serializer->serializeName(name);
115  }
116 
117  tcd->m_objectType = m_objectType;
118  tcd->m_needsFeedback = m_needsFeedback;
119  tcd->m_overrideNumSolverIterations = m_overrideNumSolverIterations;
120  tcd->m_breakingImpulseThreshold = m_breakingImpulseThreshold;
121  tcd->m_isEnabled = m_isEnabled ? 1 : 0;
122 
123  tcd->m_userConstraintId = m_userConstraintId;
124  tcd->m_userConstraintType = m_userConstraintType;
125 
126  tcd->m_appliedImpulse = m_appliedImpulse;
127  tcd->m_dbgDrawSize = m_dbgDrawSize;
128 
129  tcd->m_disableCollisionsBetweenLinkedBodies = false;
130 
131  int i;
132  for (i = 0; i < m_rbA.getNumConstraintRefs(); i++)
133  if (m_rbA.getConstraintRef(i) == this)
134  tcd->m_disableCollisionsBetweenLinkedBodies = true;
135  for (i = 0; i < m_rbB.getNumConstraintRefs(); i++)
136  if (m_rbB.getConstraintRef(i) == this)
137  tcd->m_disableCollisionsBetweenLinkedBodies = true;
138 
140 }
141 
143 {
144  static btRigidBody s_fixed(0, 0, 0);
145  s_fixed.setMassProps(btScalar(0.), btVector3(btScalar(0.), btScalar(0.), btScalar(0.)));
146  return s_fixed;
147 }
148 
149 void btAngularLimit::set(btScalar low, btScalar high, btScalar _softness, btScalar _biasFactor, btScalar _relaxationFactor)
150 {
151  m_halfRange = (high - low) / 2.0f;
153  m_softness = _softness;
154  m_biasFactor = _biasFactor;
155  m_relaxationFactor = _relaxationFactor;
156 }
157 
159 {
160  m_correction = 0.0f;
161  m_sign = 0.0f;
162  m_solveLimit = false;
163 
164  if (m_halfRange >= 0.0f)
165  {
166  btScalar deviation = btNormalizeAngle(angle - m_center);
167  if (deviation < -m_halfRange)
168  {
169  m_solveLimit = true;
170  m_correction = -(deviation + m_halfRange);
171  m_sign = +1.0f;
172  }
173  else if (deviation > m_halfRange)
174  {
175  m_solveLimit = true;
176  m_correction = m_halfRange - deviation;
177  m_sign = -1.0f;
178  }
179  }
180 }
181 
183 {
184  return m_correction * m_sign;
185 }
186 
187 void btAngularLimit::fit(btScalar& angle) const
188 {
189  if (m_halfRange > 0.0f)
190  {
191  btScalar relativeAngle = btNormalizeAngle(angle - m_center);
192  if (!btEqual(relativeAngle, m_halfRange))
193  {
194  if (relativeAngle > 0.0f)
195  {
196  angle = getHigh();
197  }
198  else
199  {
200  angle = getLow();
201  }
202  }
203  }
204 }
205 
207 {
209 }
210 
212 {
214 }
btRigidBody & m_rbA
virtual void * getUniquePointer(void *oldPtr)=0
bool btEqual(btScalar a, btScalar eps)
Definition: btScalar.h:554
#define DEFAULT_DEBUGDRAW_SIZE
#define btRigidBodyData
Definition: btRigidBody.h:35
btScalar m_breakingImpulseThreshold
#define SIMD_INFINITY
Definition: btScalar.h:524
#define btTypedConstraintDataName
void set(btScalar low, btScalar high, btScalar _softness=0.9f, btScalar _biasFactor=0.3f, btScalar _relaxationFactor=1.0f)
Sets all limit&#39;s parameters.
btScalar m_relaxationFactor
void fit(btScalar &angle) const
Checks given angle against limit.
#define btTypedConstraintData2
The btRigidBody is the main class for rigid body objects.
Definition: btRigidBody.h:59
btTypedConstraintType
btScalar getError() const
Returns correction value multiplied by sign value.
btScalar getLow() const
btVector3 can be used to represent 3D points and vectors.
Definition: btVector3.h:80
btScalar getHigh() const
btScalar btNormalizeAngle(btScalar angleInRadians)
Definition: btScalar.h:761
static btRigidBody & getFixedBody()
btTypedConstraint * getConstraintRef(int index)
Definition: btRigidBody.h:501
void setMassProps(btScalar mass, const btVector3 &inertia)
btRigidBody & m_rbB
rudimentary class to provide type info
Definition: btScalar.h:779
virtual const char * serialize(void *dataBuffer, btSerializer *serializer) const
fills the dataBuffer and returns the struct name (and 0 on failure)
virtual void serializeName(const char *ptr)=0
btScalar getMotorFactor(btScalar pos, btScalar lowLim, btScalar uppLim, btScalar vel, btScalar timeFact)
internal method used by the constraint solver, don&#39;t use them directly
btTypedConstraint(btTypedConstraintType type, btRigidBody &rbA)
void test(const btScalar angle)
Checks conastaint angle against limit.
virtual const char * findNameForPointer(const void *ptr) const =0
float btScalar
The btScalar type abstracts floating point numbers, to easily switch between double and single floati...
Definition: btScalar.h:294
int m_objectType
Definition: btScalar.h:785
int getNumConstraintRefs() const
Definition: btRigidBody.h:506