503 lines
16 KiB
C++
503 lines
16 KiB
C++
/*
|
|
Bullet Continuous Collision Detection and Physics Library
|
|
Copyright (c) 2003-2006 Erwin Coumans http://continuousphysics.com/Bullet/
|
|
|
|
This software is provided 'as-is', without any express or implied warranty.
|
|
In no event will the authors be held liable for any damages arising from the use of this software.
|
|
Permission is granted to anyone to use this software for any purpose,
|
|
including commercial applications, and to alter it and redistribute it freely,
|
|
subject to the following restrictions:
|
|
|
|
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.
|
|
2. Altered source versions must be plainly marked as such, and must not be misrepresented as being the original software.
|
|
3. This notice may not be removed or altered from any source distribution.
|
|
*/
|
|
|
|
#include "btRigidBody.h"
|
|
#include "BulletCollision/CollisionShapes/btConvexShape.h"
|
|
#include "LinearMath/btMinMax.h"
|
|
#include "LinearMath/btTransformUtil.h"
|
|
#include "LinearMath/btMotionState.h"
|
|
#include "BulletDynamics/ConstraintSolver/btTypedConstraint.h"
|
|
#include "LinearMath/btSerializer.h"
|
|
|
|
//'temporarily' global variables
|
|
btScalar gDeactivationTime = btScalar(2.);
|
|
bool gDisableDeactivation = false;
|
|
static int uniqueId = 0;
|
|
|
|
btRigidBody::btRigidBody(const btRigidBody::btRigidBodyConstructionInfo& constructionInfo)
|
|
{
|
|
setupRigidBody(constructionInfo);
|
|
}
|
|
|
|
btRigidBody::btRigidBody(btScalar mass, btMotionState* motionState, btCollisionShape* collisionShape, const btVector3& localInertia)
|
|
{
|
|
btRigidBodyConstructionInfo cinfo(mass, motionState, collisionShape, localInertia);
|
|
setupRigidBody(cinfo);
|
|
}
|
|
|
|
void btRigidBody::setupRigidBody(const btRigidBody::btRigidBodyConstructionInfo& constructionInfo)
|
|
{
|
|
m_internalType = CO_RIGID_BODY;
|
|
|
|
m_linearVelocity.setValue(btScalar(0.0), btScalar(0.0), btScalar(0.0));
|
|
m_angularVelocity.setValue(btScalar(0.), btScalar(0.), btScalar(0.));
|
|
m_angularFactor.setValue(1, 1, 1);
|
|
m_linearFactor.setValue(1, 1, 1);
|
|
m_gravity.setValue(btScalar(0.0), btScalar(0.0), btScalar(0.0));
|
|
m_gravity_acceleration.setValue(btScalar(0.0), btScalar(0.0), btScalar(0.0));
|
|
m_totalForce.setValue(btScalar(0.0), btScalar(0.0), btScalar(0.0));
|
|
m_totalTorque.setValue(btScalar(0.0), btScalar(0.0), btScalar(0.0)),
|
|
setDamping(constructionInfo.m_linearDamping, constructionInfo.m_angularDamping);
|
|
|
|
m_linearSleepingThreshold = constructionInfo.m_linearSleepingThreshold;
|
|
m_angularSleepingThreshold = constructionInfo.m_angularSleepingThreshold;
|
|
m_optionalMotionState = constructionInfo.m_motionState;
|
|
m_contactSolverType = 0;
|
|
m_frictionSolverType = 0;
|
|
m_additionalDamping = constructionInfo.m_additionalDamping;
|
|
m_additionalDampingFactor = constructionInfo.m_additionalDampingFactor;
|
|
m_additionalLinearDampingThresholdSqr = constructionInfo.m_additionalLinearDampingThresholdSqr;
|
|
m_additionalAngularDampingThresholdSqr = constructionInfo.m_additionalAngularDampingThresholdSqr;
|
|
m_additionalAngularDampingFactor = constructionInfo.m_additionalAngularDampingFactor;
|
|
|
|
if (m_optionalMotionState)
|
|
{
|
|
m_optionalMotionState->getWorldTransform(m_worldTransform);
|
|
}
|
|
else
|
|
{
|
|
m_worldTransform = constructionInfo.m_startWorldTransform;
|
|
}
|
|
|
|
m_interpolationWorldTransform = m_worldTransform;
|
|
m_interpolationLinearVelocity.setValue(0, 0, 0);
|
|
m_interpolationAngularVelocity.setValue(0, 0, 0);
|
|
|
|
//moved to btCollisionObject
|
|
m_friction = constructionInfo.m_friction;
|
|
m_rollingFriction = constructionInfo.m_rollingFriction;
|
|
m_spinningFriction = constructionInfo.m_spinningFriction;
|
|
|
|
m_restitution = constructionInfo.m_restitution;
|
|
|
|
setCollisionShape(constructionInfo.m_collisionShape);
|
|
m_debugBodyId = uniqueId++;
|
|
|
|
setMassProps(constructionInfo.m_mass, constructionInfo.m_localInertia);
|
|
updateInertiaTensor();
|
|
|
|
m_rigidbodyFlags = BT_ENABLE_GYROSCOPIC_FORCE_IMPLICIT_BODY;
|
|
|
|
m_deltaLinearVelocity.setZero();
|
|
m_deltaAngularVelocity.setZero();
|
|
m_invMass = m_inverseMass * m_linearFactor;
|
|
m_pushVelocity.setZero();
|
|
m_turnVelocity.setZero();
|
|
}
|
|
|
|
void btRigidBody::predictIntegratedTransform(btScalar timeStep, btTransform& predictedTransform)
|
|
{
|
|
btTransformUtil::integrateTransform(m_worldTransform, m_linearVelocity, m_angularVelocity, timeStep, predictedTransform);
|
|
}
|
|
|
|
void btRigidBody::saveKinematicState(btScalar timeStep)
|
|
{
|
|
//todo: clamp to some (user definable) safe minimum timestep, to limit maximum angular/linear velocities
|
|
if (timeStep != btScalar(0.))
|
|
{
|
|
//if we use motionstate to synchronize world transforms, get the new kinematic/animated world transform
|
|
if (getMotionState())
|
|
getMotionState()->getWorldTransform(m_worldTransform);
|
|
btVector3 linVel, angVel;
|
|
|
|
btTransformUtil::calculateVelocity(m_interpolationWorldTransform, m_worldTransform, timeStep, m_linearVelocity, m_angularVelocity);
|
|
m_interpolationLinearVelocity = m_linearVelocity;
|
|
m_interpolationAngularVelocity = m_angularVelocity;
|
|
m_interpolationWorldTransform = m_worldTransform;
|
|
//printf("angular = %f %f %f\n",m_angularVelocity.getX(),m_angularVelocity.getY(),m_angularVelocity.getZ());
|
|
}
|
|
}
|
|
|
|
void btRigidBody::getAabb(btVector3& aabbMin, btVector3& aabbMax) const
|
|
{
|
|
getCollisionShape()->getAabb(m_worldTransform, aabbMin, aabbMax);
|
|
}
|
|
|
|
void btRigidBody::setGravity(const btVector3& acceleration)
|
|
{
|
|
if (m_inverseMass != btScalar(0.0))
|
|
{
|
|
m_gravity = acceleration * (btScalar(1.0) / m_inverseMass);
|
|
}
|
|
m_gravity_acceleration = acceleration;
|
|
}
|
|
|
|
void btRigidBody::setDamping(btScalar lin_damping, btScalar ang_damping)
|
|
{
|
|
#ifdef BT_USE_OLD_DAMPING_METHOD
|
|
m_linearDamping = btMax(lin_damping, btScalar(0.0));
|
|
m_angularDamping = btMax(ang_damping, btScalar(0.0));
|
|
#else
|
|
m_linearDamping = btClamped(lin_damping, btScalar(0.0), btScalar(1.0));
|
|
m_angularDamping = btClamped(ang_damping, btScalar(0.0), btScalar(1.0));
|
|
#endif
|
|
}
|
|
|
|
///applyDamping damps the velocity, using the given m_linearDamping and m_angularDamping
|
|
void btRigidBody::applyDamping(btScalar timeStep)
|
|
{
|
|
//On new damping: see discussion/issue report here: http://code.google.com/p/bullet/issues/detail?id=74
|
|
//todo: do some performance comparisons (but other parts of the engine are probably bottleneck anyway
|
|
|
|
#ifdef BT_USE_OLD_DAMPING_METHOD
|
|
m_linearVelocity *= btMax((btScalar(1.0) - timeStep * m_linearDamping), btScalar(0.0));
|
|
m_angularVelocity *= btMax((btScalar(1.0) - timeStep * m_angularDamping), btScalar(0.0));
|
|
#else
|
|
m_linearVelocity *= btPow(btScalar(1) - m_linearDamping, timeStep);
|
|
m_angularVelocity *= btPow(btScalar(1) - m_angularDamping, timeStep);
|
|
#endif
|
|
|
|
if (m_additionalDamping)
|
|
{
|
|
//Additional damping can help avoiding lowpass jitter motion, help stability for ragdolls etc.
|
|
//Such damping is undesirable, so once the overall simulation quality of the rigid body dynamics system has improved, this should become obsolete
|
|
if ((m_angularVelocity.length2() < m_additionalAngularDampingThresholdSqr) &&
|
|
(m_linearVelocity.length2() < m_additionalLinearDampingThresholdSqr))
|
|
{
|
|
m_angularVelocity *= m_additionalDampingFactor;
|
|
m_linearVelocity *= m_additionalDampingFactor;
|
|
}
|
|
|
|
btScalar speed = m_linearVelocity.length();
|
|
if (speed < m_linearDamping)
|
|
{
|
|
btScalar dampVel = btScalar(0.005);
|
|
if (speed > dampVel)
|
|
{
|
|
btVector3 dir = m_linearVelocity.normalized();
|
|
m_linearVelocity -= dir * dampVel;
|
|
}
|
|
else
|
|
{
|
|
m_linearVelocity.setValue(btScalar(0.), btScalar(0.), btScalar(0.));
|
|
}
|
|
}
|
|
|
|
btScalar angSpeed = m_angularVelocity.length();
|
|
if (angSpeed < m_angularDamping)
|
|
{
|
|
btScalar angDampVel = btScalar(0.005);
|
|
if (angSpeed > angDampVel)
|
|
{
|
|
btVector3 dir = m_angularVelocity.normalized();
|
|
m_angularVelocity -= dir * angDampVel;
|
|
}
|
|
else
|
|
{
|
|
m_angularVelocity.setValue(btScalar(0.), btScalar(0.), btScalar(0.));
|
|
}
|
|
}
|
|
}
|
|
}
|
|
|
|
void btRigidBody::applyGravity()
|
|
{
|
|
if (isStaticOrKinematicObject())
|
|
return;
|
|
|
|
applyCentralForce(m_gravity);
|
|
}
|
|
|
|
void btRigidBody::clearGravity()
|
|
{
|
|
if (isStaticOrKinematicObject())
|
|
return;
|
|
|
|
applyCentralForce(-m_gravity);
|
|
}
|
|
|
|
void btRigidBody::proceedToTransform(const btTransform& newTrans)
|
|
{
|
|
setCenterOfMassTransform(newTrans);
|
|
}
|
|
|
|
void btRigidBody::setMassProps(btScalar mass, const btVector3& inertia)
|
|
{
|
|
if (mass == btScalar(0.))
|
|
{
|
|
m_collisionFlags |= btCollisionObject::CF_STATIC_OBJECT;
|
|
m_inverseMass = btScalar(0.);
|
|
}
|
|
else
|
|
{
|
|
m_collisionFlags &= (~btCollisionObject::CF_STATIC_OBJECT);
|
|
m_inverseMass = btScalar(1.0) / mass;
|
|
}
|
|
|
|
//Fg = m * a
|
|
m_gravity = mass * m_gravity_acceleration;
|
|
|
|
m_invInertiaLocal.setValue(inertia.x() != btScalar(0.0) ? btScalar(1.0) / inertia.x() : btScalar(0.0),
|
|
inertia.y() != btScalar(0.0) ? btScalar(1.0) / inertia.y() : btScalar(0.0),
|
|
inertia.z() != btScalar(0.0) ? btScalar(1.0) / inertia.z() : btScalar(0.0));
|
|
|
|
m_invMass = m_linearFactor * m_inverseMass;
|
|
}
|
|
|
|
void btRigidBody::updateInertiaTensor()
|
|
{
|
|
m_invInertiaTensorWorld = m_worldTransform.getBasis().scaled(m_invInertiaLocal) * m_worldTransform.getBasis().transpose();
|
|
}
|
|
|
|
btVector3 btRigidBody::getLocalInertia() const
|
|
{
|
|
btVector3 inertiaLocal;
|
|
const btVector3 inertia = m_invInertiaLocal;
|
|
inertiaLocal.setValue(inertia.x() != btScalar(0.0) ? btScalar(1.0) / inertia.x() : btScalar(0.0),
|
|
inertia.y() != btScalar(0.0) ? btScalar(1.0) / inertia.y() : btScalar(0.0),
|
|
inertia.z() != btScalar(0.0) ? btScalar(1.0) / inertia.z() : btScalar(0.0));
|
|
return inertiaLocal;
|
|
}
|
|
|
|
inline btVector3 evalEulerEqn(const btVector3& w1, const btVector3& w0, const btVector3& T, const btScalar dt,
|
|
const btMatrix3x3& I)
|
|
{
|
|
const btVector3 w2 = I * w1 + w1.cross(I * w1) * dt - (T * dt + I * w0);
|
|
return w2;
|
|
}
|
|
|
|
inline btMatrix3x3 evalEulerEqnDeriv(const btVector3& w1, const btVector3& w0, const btScalar dt,
|
|
const btMatrix3x3& I)
|
|
{
|
|
btMatrix3x3 w1x, Iw1x;
|
|
const btVector3 Iwi = (I * w1);
|
|
w1.getSkewSymmetricMatrix(&w1x[0], &w1x[1], &w1x[2]);
|
|
Iwi.getSkewSymmetricMatrix(&Iw1x[0], &Iw1x[1], &Iw1x[2]);
|
|
|
|
const btMatrix3x3 dfw1 = I + (w1x * I - Iw1x) * dt;
|
|
return dfw1;
|
|
}
|
|
|
|
btVector3 btRigidBody::computeGyroscopicForceExplicit(btScalar maxGyroscopicForce) const
|
|
{
|
|
btVector3 inertiaLocal = getLocalInertia();
|
|
btMatrix3x3 inertiaTensorWorld = getWorldTransform().getBasis().scaled(inertiaLocal) * getWorldTransform().getBasis().transpose();
|
|
btVector3 tmp = inertiaTensorWorld * getAngularVelocity();
|
|
btVector3 gf = getAngularVelocity().cross(tmp);
|
|
btScalar l2 = gf.length2();
|
|
if (l2 > maxGyroscopicForce * maxGyroscopicForce)
|
|
{
|
|
gf *= btScalar(1.) / btSqrt(l2) * maxGyroscopicForce;
|
|
}
|
|
return gf;
|
|
}
|
|
|
|
btVector3 btRigidBody::computeGyroscopicImpulseImplicit_Body(btScalar step) const
|
|
{
|
|
btVector3 idl = getLocalInertia();
|
|
btVector3 omega1 = getAngularVelocity();
|
|
btQuaternion q = getWorldTransform().getRotation();
|
|
|
|
// Convert to body coordinates
|
|
btVector3 omegab = quatRotate(q.inverse(), omega1);
|
|
btMatrix3x3 Ib;
|
|
Ib.setValue(idl.x(), 0, 0,
|
|
0, idl.y(), 0,
|
|
0, 0, idl.z());
|
|
|
|
btVector3 ibo = Ib * omegab;
|
|
|
|
// Residual vector
|
|
btVector3 f = step * omegab.cross(ibo);
|
|
|
|
btMatrix3x3 skew0;
|
|
omegab.getSkewSymmetricMatrix(&skew0[0], &skew0[1], &skew0[2]);
|
|
btVector3 om = Ib * omegab;
|
|
btMatrix3x3 skew1;
|
|
om.getSkewSymmetricMatrix(&skew1[0], &skew1[1], &skew1[2]);
|
|
|
|
// Jacobian
|
|
btMatrix3x3 J = Ib + (skew0 * Ib - skew1) * step;
|
|
|
|
// btMatrix3x3 Jinv = J.inverse();
|
|
// btVector3 omega_div = Jinv*f;
|
|
btVector3 omega_div = J.solve33(f);
|
|
|
|
// Single Newton-Raphson update
|
|
omegab = omegab - omega_div; //Solve33(J, f);
|
|
// Back to world coordinates
|
|
btVector3 omega2 = quatRotate(q, omegab);
|
|
btVector3 gf = omega2 - omega1;
|
|
return gf;
|
|
}
|
|
|
|
btVector3 btRigidBody::computeGyroscopicImpulseImplicit_World(btScalar step) const
|
|
{
|
|
// use full newton-euler equations. common practice to drop the wxIw term. want it for better tumbling behavior.
|
|
// calculate using implicit euler step so it's stable.
|
|
|
|
const btVector3 inertiaLocal = getLocalInertia();
|
|
const btVector3 w0 = getAngularVelocity();
|
|
|
|
btMatrix3x3 I;
|
|
|
|
I = m_worldTransform.getBasis().scaled(inertiaLocal) *
|
|
m_worldTransform.getBasis().transpose();
|
|
|
|
// use newtons method to find implicit solution for new angular velocity (w')
|
|
// f(w') = -(T*step + Iw) + Iw' + w' + w'xIw'*step = 0
|
|
// df/dw' = I + 1xIw'*step + w'xI*step
|
|
|
|
btVector3 w1 = w0;
|
|
|
|
// one step of newton's method
|
|
{
|
|
const btVector3 fw = evalEulerEqn(w1, w0, btVector3(0, 0, 0), step, I);
|
|
const btMatrix3x3 dfw = evalEulerEqnDeriv(w1, w0, step, I);
|
|
|
|
btVector3 dw;
|
|
dw = dfw.solve33(fw);
|
|
//const btMatrix3x3 dfw_inv = dfw.inverse();
|
|
//dw = dfw_inv*fw;
|
|
|
|
w1 -= dw;
|
|
}
|
|
|
|
btVector3 gf = (w1 - w0);
|
|
return gf;
|
|
}
|
|
|
|
void btRigidBody::integrateVelocities(btScalar step)
|
|
{
|
|
if (isStaticOrKinematicObject())
|
|
return;
|
|
|
|
m_linearVelocity += m_totalForce * (m_inverseMass * step);
|
|
m_angularVelocity += m_invInertiaTensorWorld * m_totalTorque * step;
|
|
|
|
#define MAX_ANGVEL SIMD_HALF_PI
|
|
/// clamp angular velocity. collision calculations will fail on higher angular velocities
|
|
btScalar angvel = m_angularVelocity.length();
|
|
if (angvel * step > MAX_ANGVEL)
|
|
{
|
|
m_angularVelocity *= (MAX_ANGVEL / step) / angvel;
|
|
}
|
|
}
|
|
|
|
btQuaternion btRigidBody::getOrientation() const
|
|
{
|
|
btQuaternion orn;
|
|
m_worldTransform.getBasis().getRotation(orn);
|
|
return orn;
|
|
}
|
|
|
|
void btRigidBody::setCenterOfMassTransform(const btTransform& xform)
|
|
{
|
|
if (isKinematicObject())
|
|
{
|
|
m_interpolationWorldTransform = m_worldTransform;
|
|
}
|
|
else
|
|
{
|
|
m_interpolationWorldTransform = xform;
|
|
}
|
|
m_interpolationLinearVelocity = getLinearVelocity();
|
|
m_interpolationAngularVelocity = getAngularVelocity();
|
|
m_worldTransform = xform;
|
|
updateInertiaTensor();
|
|
}
|
|
|
|
void btRigidBody::addConstraintRef(btTypedConstraint* c)
|
|
{
|
|
///disable collision with the 'other' body
|
|
|
|
int index = m_constraintRefs.findLinearSearch(c);
|
|
//don't add constraints that are already referenced
|
|
//btAssert(index == m_constraintRefs.size());
|
|
if (index == m_constraintRefs.size())
|
|
{
|
|
m_constraintRefs.push_back(c);
|
|
btCollisionObject* colObjA = &c->getRigidBodyA();
|
|
btCollisionObject* colObjB = &c->getRigidBodyB();
|
|
if (colObjA == this)
|
|
{
|
|
colObjA->setIgnoreCollisionCheck(colObjB, true);
|
|
}
|
|
else
|
|
{
|
|
colObjB->setIgnoreCollisionCheck(colObjA, true);
|
|
}
|
|
}
|
|
}
|
|
|
|
void btRigidBody::removeConstraintRef(btTypedConstraint* c)
|
|
{
|
|
int index = m_constraintRefs.findLinearSearch(c);
|
|
//don't remove constraints that are not referenced
|
|
if (index < m_constraintRefs.size())
|
|
{
|
|
m_constraintRefs.remove(c);
|
|
btCollisionObject* colObjA = &c->getRigidBodyA();
|
|
btCollisionObject* colObjB = &c->getRigidBodyB();
|
|
if (colObjA == this)
|
|
{
|
|
colObjA->setIgnoreCollisionCheck(colObjB, false);
|
|
}
|
|
else
|
|
{
|
|
colObjB->setIgnoreCollisionCheck(colObjA, false);
|
|
}
|
|
}
|
|
}
|
|
|
|
int btRigidBody::calculateSerializeBufferSize() const
|
|
{
|
|
int sz = sizeof(btRigidBodyData);
|
|
return sz;
|
|
}
|
|
|
|
///fills the dataBuffer and returns the struct name (and 0 on failure)
|
|
const char* btRigidBody::serialize(void* dataBuffer, class btSerializer* serializer) const
|
|
{
|
|
btRigidBodyData* rbd = (btRigidBodyData*)dataBuffer;
|
|
|
|
btCollisionObject::serialize(&rbd->m_collisionObjectData, serializer);
|
|
|
|
m_invInertiaTensorWorld.serialize(rbd->m_invInertiaTensorWorld);
|
|
m_linearVelocity.serialize(rbd->m_linearVelocity);
|
|
m_angularVelocity.serialize(rbd->m_angularVelocity);
|
|
rbd->m_inverseMass = m_inverseMass;
|
|
m_angularFactor.serialize(rbd->m_angularFactor);
|
|
m_linearFactor.serialize(rbd->m_linearFactor);
|
|
m_gravity.serialize(rbd->m_gravity);
|
|
m_gravity_acceleration.serialize(rbd->m_gravity_acceleration);
|
|
m_invInertiaLocal.serialize(rbd->m_invInertiaLocal);
|
|
m_totalForce.serialize(rbd->m_totalForce);
|
|
m_totalTorque.serialize(rbd->m_totalTorque);
|
|
rbd->m_linearDamping = m_linearDamping;
|
|
rbd->m_angularDamping = m_angularDamping;
|
|
rbd->m_additionalDamping = m_additionalDamping;
|
|
rbd->m_additionalDampingFactor = m_additionalDampingFactor;
|
|
rbd->m_additionalLinearDampingThresholdSqr = m_additionalLinearDampingThresholdSqr;
|
|
rbd->m_additionalAngularDampingThresholdSqr = m_additionalAngularDampingThresholdSqr;
|
|
rbd->m_additionalAngularDampingFactor = m_additionalAngularDampingFactor;
|
|
rbd->m_linearSleepingThreshold = m_linearSleepingThreshold;
|
|
rbd->m_angularSleepingThreshold = m_angularSleepingThreshold;
|
|
|
|
// Fill padding with zeros to appease msan.
|
|
#ifdef BT_USE_DOUBLE_PRECISION
|
|
memset(rbd->m_padding, 0, sizeof(rbd->m_padding));
|
|
#endif
|
|
|
|
return btRigidBodyDataName;
|
|
}
|
|
|
|
void btRigidBody::serializeSingleObject(class btSerializer* serializer) const
|
|
{
|
|
btChunk* chunk = serializer->allocate(calculateSerializeBufferSize(), 1);
|
|
const char* structType = serialize(chunk->m_oldPtr, serializer);
|
|
serializer->finalizeChunk(chunk, structType, BT_RIGIDBODY_CODE, (void*)this);
|
|
}
|