dali-physics/third-party/bullet3/src/Bullet3Dynamics/ConstraintSolver/b3FixedConstraint.cpp

   1
   2 #include "b3FixedConstraint.h"
   3 #include "Bullet3Collision/NarrowPhaseCollision/shared/b3RigidBodyData.h"
   4 #include "Bullet3Common/b3TransformUtil.h"
   5 #include <new>
   6
   7 b3FixedConstraint::b3FixedConstraint(int rbA, int rbB, const b3Transform& frameInA, const b3Transform& frameInB)
   8         : b3TypedConstraint(B3_FIXED_CONSTRAINT_TYPE, rbA, rbB)
   9 {
  10         m_pivotInA = frameInA.getOrigin();
  11         m_pivotInB = frameInB.getOrigin();
  12         m_relTargetAB = frameInA.getRotation() * frameInB.getRotation().inverse();
  13 }
  14
  15 b3FixedConstraint::~b3FixedConstraint()
  16 {
  17 }
  18
  19 void b3FixedConstraint::getInfo1(b3ConstraintInfo1* info, const b3RigidBodyData* bodies)
  20 {
  21         info->m_numConstraintRows = 6;
  22         info->nub = 6;
  23 }
  24
  25 void b3FixedConstraint::getInfo2(b3ConstraintInfo2* info, const b3RigidBodyData* bodies)
  26 {
  27         //fix the 3 linear degrees of freedom
  28
  29         const b3Vector3& worldPosA = bodies[m_rbA].m_pos;
  30         const b3Quaternion& worldOrnA = bodies[m_rbA].m_quat;
  31         const b3Vector3& worldPosB = bodies[m_rbB].m_pos;
  32         const b3Quaternion& worldOrnB = bodies[m_rbB].m_quat;
  33
  34         info->m_J1linearAxis[0] = 1;
  35         info->m_J1linearAxis[info->rowskip + 1] = 1;
  36         info->m_J1linearAxis[2 * info->rowskip + 2] = 1;
  37
  38         b3Vector3 a1 = b3QuatRotate(worldOrnA, m_pivotInA);
  39         {
  40                 b3Vector3* angular0 = (b3Vector3*)(info->m_J1angularAxis);
  41                 b3Vector3* angular1 = (b3Vector3*)(info->m_J1angularAxis + info->rowskip);
  42                 b3Vector3* angular2 = (b3Vector3*)(info->m_J1angularAxis + 2 * info->rowskip);
  43                 b3Vector3 a1neg = -a1;
  44                 a1neg.getSkewSymmetricMatrix(angular0, angular1, angular2);
  45         }
  46
  47         if (info->m_J2linearAxis)
  48         {
  49                 info->m_J2linearAxis[0] = -1;
  50                 info->m_J2linearAxis[info->rowskip + 1] = -1;
  51                 info->m_J2linearAxis[2 * info->rowskip + 2] = -1;
  52         }
  53
  54         b3Vector3 a2 = b3QuatRotate(worldOrnB, m_pivotInB);
  55
  56         {
  57                 //      b3Vector3 a2n = -a2;
  58                 b3Vector3* angular0 = (b3Vector3*)(info->m_J2angularAxis);
  59                 b3Vector3* angular1 = (b3Vector3*)(info->m_J2angularAxis + info->rowskip);
  60                 b3Vector3* angular2 = (b3Vector3*)(info->m_J2angularAxis + 2 * info->rowskip);
  61                 a2.getSkewSymmetricMatrix(angular0, angular1, angular2);
  62         }
  63
  64         // set right hand side for the linear dofs
  65         b3Scalar k = info->fps * info->erp;
  66         b3Vector3 linearError = k * (a2 + worldPosB - a1 - worldPosA);
  67         int j;
  68         for (j = 0; j < 3; j++)
  69         {
  70                 info->m_constraintError[j * info->rowskip] = linearError[j];
  71                 //printf("info->m_constraintError[%d]=%f\n",j,info->m_constraintError[j]);
  72         }
  73
  74         //fix the 3 angular degrees of freedom
  75
  76         int start_row = 3;
  77         int s = info->rowskip;
  78         int start_index = start_row * s;
  79
  80         // 3 rows to make body rotations equal
  81         info->m_J1angularAxis[start_index] = 1;
  82         info->m_J1angularAxis[start_index + s + 1] = 1;
  83         info->m_J1angularAxis[start_index + s * 2 + 2] = 1;
  84         if (info->m_J2angularAxis)
  85         {
  86                 info->m_J2angularAxis[start_index] = -1;
  87                 info->m_J2angularAxis[start_index + s + 1] = -1;
  88                 info->m_J2angularAxis[start_index + s * 2 + 2] = -1;
  89         }
  90
  91         // set right hand side for the angular dofs
  92
  93         b3Vector3 diff;
  94         b3Scalar angle;
  95         b3Quaternion qrelCur = worldOrnA * worldOrnB.inverse();
  96
  97         b3TransformUtil::calculateDiffAxisAngleQuaternion(m_relTargetAB, qrelCur, diff, angle);
  98         diff *= -angle;
  99         for (j = 0; j < 3; j++)
 100         {
 101                 info->m_constraintError[(3 + j) * info->rowskip] = k * diff[j];
 102         }
 103 }