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add support for anchor constraint between deformable and rigid

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This commit is contained in:
Xuchen Han
2019-10-16 19:23:01 -07:00
parent 3d622a3bee
commit 60dfe1fe69
11 changed files with 487 additions and 2 deletions
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236
examples/DeformableDemo/DeformableClothAnchor.cpp Normal file
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@@ -0,0 +1,236 @@
/*
Bullet Continuous Collision Detection and Physics Library
Copyright (c) 2019 Google Inc. http://bulletphysics.org
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 "DeformableClothAnchor.h"
///btBulletDynamicsCommon.h is the main Bullet include file, contains most common include files.
#include "btBulletDynamicsCommon.h"
#include "BulletSoftBody/btDeformableMultiBodyDynamicsWorld.h"
#include "BulletSoftBody/btSoftBody.h"
#include "BulletSoftBody/btSoftBodyHelpers.h"
#include "BulletSoftBody/btDeformableBodySolver.h"
#include "BulletSoftBody/btSoftBodyRigidBodyCollisionConfiguration.h"
#include "BulletDynamics/Featherstone/btMultiBodyConstraintSolver.h"
#include <stdio.h> //printf debugging
#include "../CommonInterfaces/CommonRigidBodyBase.h"
#include "../Utils/b3ResourcePath.h"
///The DeformableClothAnchor shows contact between deformable objects and rigid objects.
class DeformableClothAnchor : public CommonRigidBodyBase
{
btAlignedObjectArray<btDeformableLagrangianForce*> m_forces;
public:
DeformableClothAnchor(struct GUIHelperInterface* helper)
: CommonRigidBodyBase(helper)
{
}
virtual ~DeformableClothAnchor()
{
}
void initPhysics();
void exitPhysics();
void resetCamera()
{
float dist = 20;
float pitch = -45;
float yaw = 100;
float targetPos[3] = {0, -3, 0};
m_guiHelper->resetCamera(dist, yaw, pitch, targetPos[0], targetPos[1], targetPos[2]);
}
void stepSimulation(float deltaTime)
{
//use a smaller internal timestep, there are stability issues
float internalTimeStep = 1. / 240.f;
m_dynamicsWorld->stepSimulation(deltaTime, 4, internalTimeStep);
}
virtual const btDeformableMultiBodyDynamicsWorld* getDeformableDynamicsWorld() const
{
///just make it a btSoftRigidDynamicsWorld please
///or we will add type checking
return (btDeformableMultiBodyDynamicsWorld*)m_dynamicsWorld;
}
virtual btDeformableMultiBodyDynamicsWorld* getDeformableDynamicsWorld()
{
///just make it a btSoftRigidDynamicsWorld please
///or we will add type checking
return (btDeformableMultiBodyDynamicsWorld*)m_dynamicsWorld;
}
virtual void renderScene()
{
CommonRigidBodyBase::renderScene();
btDeformableMultiBodyDynamicsWorld* deformableWorld = getDeformableDynamicsWorld();
for (int i = 0; i < deformableWorld->getSoftBodyArray().size(); i++)
{
btSoftBody* psb = (btSoftBody*)deformableWorld->getSoftBodyArray()[i];
//if (softWorld->getDebugDrawer() && !(softWorld->getDebugDrawer()->getDebugMode() & (btIDebugDraw::DBG_DrawWireframe)))
{
btSoftBodyHelpers::DrawFrame(psb, deformableWorld->getDebugDrawer());
btSoftBodyHelpers::Draw(psb, deformableWorld->getDebugDrawer(), deformableWorld->getDrawFlags());
}
}
}
};
void DeformableClothAnchor::initPhysics()
{
m_guiHelper->setUpAxis(1);
///collision configuration contains default setup for memory, collision setup
m_collisionConfiguration = new btSoftBodyRigidBodyCollisionConfiguration();
///use the default collision dispatcher. For parallel processing you can use a diffent dispatcher (see Extras/BulletMultiThreaded)
m_dispatcher = new btCollisionDispatcher(m_collisionConfiguration);
m_broadphase = new btDbvtBroadphase();
btDeformableBodySolver* deformableBodySolver = new btDeformableBodySolver();
///the default constraint solver. For parallel processing you can use a different solver (see Extras/BulletMultiThreaded)
btDeformableMultiBodyConstraintSolver* sol = new btDeformableMultiBodyConstraintSolver();
sol->setDeformableSolver(deformableBodySolver);
m_solver = sol;
m_dynamicsWorld = new btDeformableMultiBodyDynamicsWorld(m_dispatcher, m_broadphase, sol, m_collisionConfiguration, deformableBodySolver);
// deformableBodySolver->setWorld(getDeformableDynamicsWorld());
// m_dynamicsWorld->getSolverInfo().m_singleAxisDeformableThreshold = 0.f;//faster but lower quality
btVector3 gravity = btVector3(0, -10, 0);
m_dynamicsWorld->setGravity(gravity);
getDeformableDynamicsWorld()->getWorldInfo().m_gravity = gravity;
// getDeformableDynamicsWorld()->before_solver_callbacks.push_back(dynamics);
m_guiHelper->createPhysicsDebugDrawer(m_dynamicsWorld);
{
///create a ground
btCollisionShape* groundShape = new btBoxShape(btVector3(btScalar(150.), btScalar(25.), btScalar(150.)));
m_collisionShapes.push_back(groundShape);
btTransform groundTransform;
groundTransform.setIdentity();
groundTransform.setOrigin(btVector3(0, -50, 0));
groundTransform.setRotation(btQuaternion(btVector3(1, 0, 0), SIMD_PI * 0.));
//We can also use DemoApplication::localCreateRigidBody, but for clarity it is provided here:
btScalar mass(0.);
//rigidbody is dynamic if and only if mass is non zero, otherwise static
bool isDynamic = (mass != 0.f);
btVector3 localInertia(0, 0, 0);
if (isDynamic)
groundShape->calculateLocalInertia(mass, localInertia);
//using motionstate is recommended, it provides interpolation capabilities, and only synchronizes 'active' objects
btDefaultMotionState* myMotionState = new btDefaultMotionState(groundTransform);
btRigidBody::btRigidBodyConstructionInfo rbInfo(mass, myMotionState, groundShape, localInertia);
btRigidBody* body = new btRigidBody(rbInfo);
body->setFriction(1);
//add the ground to the dynamics world
m_dynamicsWorld->addRigidBody(body);
}
// create a piece of cloth
{
const btScalar s = 4;
const btScalar h = 6;
const int r = 9;
btSoftBody* psb = btSoftBodyHelpers::CreatePatch(getDeformableDynamicsWorld()->getWorldInfo(), btVector3(-s, h, -s),
btVector3(+s, h, -s),
btVector3(-s, h, +s),
btVector3(+s, h, +s), r, r, 4 + 8, true);
psb->getCollisionShape()->setMargin(0.1);
psb->generateBendingConstraints(2);
psb->setTotalMass(1);
psb->m_cfg.kKHR = 1; // collision hardness with kinematic objects
psb->m_cfg.kCHR = 1; // collision hardness with rigid body
psb->m_cfg.kDF = 2;
psb->m_cfg.collisions = btSoftBody::fCollision::SDF_RD;
getDeformableDynamicsWorld()->addSoftBody(psb);
btDeformableMassSpringForce* mass_spring = new btDeformableMassSpringForce(100,1, true);
getDeformableDynamicsWorld()->addForce(psb, mass_spring);
m_forces.push_back(mass_spring);
btDeformableGravityForce* gravity_force = new btDeformableGravityForce(gravity);
getDeformableDynamicsWorld()->addForce(psb, gravity_force);
m_forces.push_back(gravity_force);
btTransform startTransform;
startTransform.setIdentity();
startTransform.setOrigin(btVector3(0, h, -(s + 3.5)));
btRigidBody* body = createRigidBody(2, startTransform, new btBoxShape(btVector3(s, 1, 3)));
psb->appendDeformableAnchor(0, body);
psb->appendDeformableAnchor(r - 1, body);
}
getDeformableDynamicsWorld()->setImplicit(false);
getDeformableDynamicsWorld()->setLineSearch(false);
m_guiHelper->autogenerateGraphicsObjects(m_dynamicsWorld);
}
void DeformableClothAnchor::exitPhysics()
{
//cleanup in the reverse order of creation/initialization
//remove the rigidbodies from the dynamics world and delete them
int i;
for (i = m_dynamicsWorld->getNumCollisionObjects() - 1; i >= 0; i--)
{
btCollisionObject* obj = m_dynamicsWorld->getCollisionObjectArray()[i];
btRigidBody* body = btRigidBody::upcast(obj);
if (body && body->getMotionState())
{
delete body->getMotionState();
}
m_dynamicsWorld->removeCollisionObject(obj);
delete obj;
}
// delete forces
for (int j = 0; j < m_forces.size(); j++)
{
btDeformableLagrangianForce* force = m_forces[j];
delete force;
}
m_forces.clear();
//delete collision shapes
for (int j = 0; j < m_collisionShapes.size(); j++)
{
btCollisionShape* shape = m_collisionShapes[j];
delete shape;
}
m_collisionShapes.clear();
delete m_dynamicsWorld;
delete m_solver;
delete m_broadphase;
delete m_dispatcher;
delete m_collisionConfiguration;
}
class CommonExampleInterface* DeformableClothAnchorCreateFunc(struct CommonExampleOptions& options)
{
return new DeformableClothAnchor(options.m_guiHelper);
}

19
examples/DeformableDemo/DeformableClothAnchor.h Normal file
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@@ -0,0 +1,19 @@
/*
Bullet Continuous Collision Detection and Physics Library
Copyright (c) 2019 Google Inc. http://bulletphysics.org
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.
*/
#ifndef DEFORMABLE_CLOTH_ANCHOR_H
#define DEFORMABLE_CLOTH_ANCHOR_H
class CommonExampleInterface* DeformableClothAnchorCreateFunc(struct CommonExampleOptions& options);
#endif //DEFORMABLE_CLOTH_ANCHOR_H

2
examples/ExampleBrowser/CMakeLists.txt
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@@ -371,6 +371,8 @@ SET(BulletExampleBrowser_SRCS
../DeformableDemo/DeformableRigid.h
../DeformableDemo/VolumetricDeformable.cpp
../DeformableDemo/VolumetricDeformable.h
../DeformableDemo/DeformableClothAnchor.cpp
../DeformableDemo/DeformableClothAnchor.h
../MultiBody/MultiDofDemo.cpp
../MultiBody/MultiDofDemo.h
../RigidBody/RigidBodySoftContact.cpp

2
examples/ExampleBrowser/ExampleEntries.cpp
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@@ -53,6 +53,7 @@
#include "../DeformableDemo/VolumetricDeformable.h"
#include "../DeformableDemo/GraspDeformable.h"
#include "../DeformableDemo/DeformableContact.h"
#include "../DeformableDemo/DeformableClothAnchor.h"
#include "../SharedMemory/PhysicsServerExampleBullet2.h"
#include "../SharedMemory/PhysicsServerExample.h"
#include "../SharedMemory/PhysicsClientExample.h"
@@ -198,6 +199,7 @@ static ExampleEntry gDefaultExamples[] =
ExampleEntry(1, "Grasp Deformable Cube", "Grasping test", PinchCreateFunc),
ExampleEntry(1, "Grasp Deformable with Motor", "Grasping test", GraspDeformableCreateFunc),
ExampleEntry(1, "Volumetric Deformable Objects", "Volumetric Deformable test", VolumetricDeformableCreateFunc),
ExampleEntry(1, "Deformable Cloth Anchor", "Deformable Anchor test", DeformableClothAnchorCreateFunc),
ExampleEntry(1, "Deformable-MultiBody Contact", "MultiBody and Deformable contact", DeformableMultibodyCreateFunc),
// ExampleEntry(1, "MultiBody Baseline", "MultiBody Baseline", MultiBodyBaselineCreateFunc),

121
src/BulletSoftBody/btDeformableContactConstraint.cpp
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@@ -15,6 +15,127 @@
#include "btDeformableContactConstraint.h"
/* ================ Deformable Node Anchor =================== */
btDeformableNodeAnchorConstraint::btDeformableNodeAnchorConstraint(const btSoftBody::DeformableNodeRigidAnchor& a)
: m_anchor(&a)
, btDeformableContactConstraint(a.m_cti.m_normal)
{
}
btDeformableNodeAnchorConstraint::btDeformableNodeAnchorConstraint(const btDeformableNodeAnchorConstraint& other)
: m_anchor(other.m_anchor)
, btDeformableContactConstraint(other)
{
}
btVector3 btDeformableNodeAnchorConstraint::getVa() const
{
const btSoftBody::sCti& cti = m_anchor->m_cti;
btVector3 va(0, 0, 0);
if (cti.m_colObj->hasContactResponse())
{
btRigidBody* rigidCol = 0;
btMultiBodyLinkCollider* multibodyLinkCol = 0;
// grab the velocity of the rigid body
if (cti.m_colObj->getInternalType() == btCollisionObject::CO_RIGID_BODY)
{
rigidCol = (btRigidBody*)btRigidBody::upcast(cti.m_colObj);
va = rigidCol ? (rigidCol->getVelocityInLocalPoint(m_anchor->m_c1)) : btVector3(0, 0, 0);
}
else if (cti.m_colObj->getInternalType() == btCollisionObject::CO_FEATHERSTONE_LINK)
{
// multibody anchor not supported yet
btAssert(false);
multibodyLinkCol = (btMultiBodyLinkCollider*)btMultiBodyLinkCollider::upcast(cti.m_colObj);
if (multibodyLinkCol)
{
const int ndof = multibodyLinkCol->m_multiBody->getNumDofs() + 6;
const btScalar* J_n = &m_anchor->jacobianData_normal.m_jacobians[0];
const btScalar* J_t1 = &m_anchor->jacobianData_t1.m_jacobians[0];
const btScalar* J_t2 = &m_anchor->jacobianData_t2.m_jacobians[0];
const btScalar* local_v = multibodyLinkCol->m_multiBody->getVelocityVector();
const btScalar* local_dv = multibodyLinkCol->m_multiBody->getDeltaVelocityVector();
// add in the normal component of the va
btScalar vel = 0.0;
for (int k = 0; k < ndof; ++k)
{
vel += (local_v[k]+local_dv[k]) * J_n[k];
}
va = cti.m_normal * vel;
// add in the tangential components of the va
vel = 0.0;
for (int k = 0; k < ndof; ++k)
{
vel += (local_v[k]+local_dv[k]) * J_t1[k];
}
va += m_anchor->t1 * vel;
vel = 0.0;
for (int k = 0; k < ndof; ++k)
{
vel += (local_v[k]+local_dv[k]) * J_t2[k];
}
va += m_anchor->t2 * vel;
}
}
}
return va;
}
btScalar btDeformableNodeAnchorConstraint::solveConstraint()
{
const btSoftBody::sCti& cti = m_anchor->m_cti;
btVector3 va = getVa();
btVector3 vb = getVb();
btVector3 vr = (vb - va);
// + (m_anchor->m_node->m_x - cti.m_colObj->getWorldTransform() * m_anchor->m_local) * 10.0
const btScalar dn = btDot(vr, cti.m_normal);
// dn is the normal component of velocity diffrerence. Approximates the residual. // todo xuchenhan@: this prob needs to be scaled by dt
btScalar residualSquare = dn*dn;
btVector3 impulse = m_anchor->m_c0 * vr;
// apply impulse to deformable nodes involved and change their velocities
applyImpulse(impulse);
// apply impulse to the rigid/multibodies involved and change their velocities
if (cti.m_colObj->getInternalType() == btCollisionObject::CO_RIGID_BODY)
{
btRigidBody* rigidCol = 0;
rigidCol = (btRigidBody*)btRigidBody::upcast(cti.m_colObj);
if (rigidCol)
{
rigidCol->applyImpulse(impulse, m_anchor->m_c1);
}
}
else if (cti.m_colObj->getInternalType() == btCollisionObject::CO_FEATHERSTONE_LINK)
{
btMultiBodyLinkCollider* multibodyLinkCol = 0;
multibodyLinkCol = (btMultiBodyLinkCollider*)btMultiBodyLinkCollider::upcast(cti.m_colObj);
if (multibodyLinkCol)
{
const btScalar* deltaV_normal = &m_anchor->jacobianData_normal.m_deltaVelocitiesUnitImpulse[0];
// apply normal component of the impulse
multibodyLinkCol->m_multiBody->applyDeltaVeeMultiDof2(deltaV_normal, impulse.dot(cti.m_normal));
// apply tangential component of the impulse
const btScalar* deltaV_t1 = &m_anchor->jacobianData_t1.m_deltaVelocitiesUnitImpulse[0];
multibodyLinkCol->m_multiBody->applyDeltaVeeMultiDof2(deltaV_t1, impulse.dot(m_anchor->t1));
const btScalar* deltaV_t2 = &m_anchor->jacobianData_t2.m_deltaVelocitiesUnitImpulse[0];
multibodyLinkCol->m_multiBody->applyDeltaVeeMultiDof2(deltaV_t2, impulse.dot(m_anchor->t2));
}
}
return residualSquare;
}
btVector3 btDeformableNodeAnchorConstraint::getVb() const
{
return m_anchor->m_node->m_v;
}
void btDeformableNodeAnchorConstraint::applyImpulse(const btVector3& impulse)
{
btVector3 dv = impulse * m_anchor->m_c2;
m_anchor->m_node->m_v -= dv;
}
/* ================ Deformable vs. Rigid =================== */
btDeformableRigidContactConstraint::btDeformableRigidContactConstraint(const btSoftBody::DeformableRigidContact& c)
: m_contact(&c)

26
src/BulletSoftBody/btDeformableContactConstraint.h
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@@ -108,6 +108,32 @@ public:
virtual void applyImpulse(const btVector3& impulse){}
};
//
// Anchor Constraint between rigid and deformable node
class btDeformableNodeAnchorConstraint : public btDeformableContactConstraint
{
public:
const btSoftBody::DeformableNodeRigidAnchor* m_anchor;
btDeformableNodeAnchorConstraint(){}
btDeformableNodeAnchorConstraint(const btSoftBody::DeformableNodeRigidAnchor& c);
btDeformableNodeAnchorConstraint(const btDeformableNodeAnchorConstraint& other);
virtual ~btDeformableNodeAnchorConstraint()
{
}
virtual btScalar solveConstraint();
// object A is the rigid/multi body, and object B is the deformable node/face
virtual btVector3 getVa() const;
// get the velocity of the deformable node in contact
virtual btVector3 getVb() const;
virtual btVector3 getDv(const btSoftBody::Node* n) const
{
return btVector3(0,0,0);
}
virtual void applyImpulse(const btVector3& impulse);
};
//
// Constraint between rigid/multi body and deformable objects
class btDeformableRigidContactConstraint : public btDeformableContactConstraint

29
src/BulletSoftBody/btDeformableContactProjection.cpp
View File

@@ -32,6 +32,14 @@ btScalar btDeformableContactProjection::update()
}
}
// anchor constraints
for (int index = 0; index < m_nodeAnchorConstraints.size(); ++index)
{
btDeformableNodeAnchorConstraint& constraint = *m_nodeAnchorConstraints.getAtIndex(index);
btScalar localResidualSquare = constraint.solveConstraint();
residualSquare = btMax(residualSquare, localResidualSquare);
}
// face constraints
for (int index = 0; index < m_allFaceConstraints.size(); ++index)
{
@@ -73,6 +81,24 @@ void btDeformableContactProjection::setConstraints()
continue;
}
// set up deformable anchors
for (int j = 0; j < psb->m_deformableAnchors.size(); ++j)
{
btSoftBody::DeformableNodeRigidAnchor& anchor = psb->m_deformableAnchors[j];
// skip fixed points
if (anchor.m_node->m_im == 0)
{
continue;
}
if (m_nodeAnchorConstraints.find(anchor.m_node->index) == NULL)
{
anchor.m_c1 = anchor.m_cti.m_colObj->getWorldTransform().getBasis() * anchor.m_local;
btDeformableNodeAnchorConstraint constraint(anchor);
m_nodeAnchorConstraints.insert(anchor.m_node->index, constraint);
}
}
// set Deformable Node vs. Rigid constraint
for (int j = 0; j < psb->m_nodeRigidContacts.size(); ++j)
{
@@ -262,7 +288,7 @@ void btDeformableContactProjection::setProjection()
bool existStaticConstraint = false;
btVector3 averagedNormal(0,0,0);
btAlignedObjectArray<btVector3> normals;
if (m_staticConstraints.find(index) != NULL)
if (m_staticConstraints.find(index) != NULL || m_nodeAnchorConstraints.find(index) != NULL)
{
existStaticConstraint = true;
hasConstraint = true;
@@ -451,6 +477,7 @@ void btDeformableContactProjection::applyDynamicFriction(TVStack& f)
void btDeformableContactProjection::reinitialize(bool nodeUpdated)
{
m_staticConstraints.clear();
m_nodeAnchorConstraints.clear();
m_nodeRigidConstraints.clear();
m_faceRigidConstraints.clear();
m_deformableConstraints.clear();

2
src/BulletSoftBody/btDeformableContactProjection.h
View File

@@ -36,6 +36,8 @@ public:
btHashMap<btHashInt, btAlignedObjectArray<btDeformableFaceRigidContactConstraint*> > m_faceRigidConstraints;
// map from node index to deformable constraint
btHashMap<btHashInt, btAlignedObjectArray<btDeformableFaceNodeContactConstraint*> > m_deformableConstraints;
// map from node index to node anchor constraint
btHashMap<btHashInt, btDeformableNodeAnchorConstraint> m_nodeAnchorConstraints;
// all constraints involving face
btAlignedObjectArray<btDeformableContactConstraint*> m_allFaceConstraints;

7
src/BulletSoftBody/btDeformableMultiBodyDynamicsWorld.cpp
View File

@@ -140,6 +140,13 @@ void btDeformableMultiBodyDynamicsWorld::integrateTransforms(btScalar timeStep)
node.m_q = node.m_x;
node.m_vn = node.m_v;
}
// enforce anchor constraints
for (int j = 0; j < psb->m_deformableAnchors.size();++j)
{
btSoftBody::DeformableNodeRigidAnchor& a = psb->m_deformableAnchors[j];
btSoftBody::Node* n = a.m_node;
n->m_x = a.m_cti.m_colObj->getWorldTransform() * a.m_local;
}
psb->interpolateRenderMesh();
}
}

35
src/BulletSoftBody/btSoftBody.cpp
View File

@@ -411,6 +411,41 @@ void btSoftBody::appendAnchor(int node, btRigidBody* body, const btVector3& loca
m_anchors.push_back(a);
}
//
void btSoftBody::appendDeformableAnchor(int node, btRigidBody* body)
{
DeformableNodeRigidAnchor c;
btSoftBody::Node& n = m_nodes[node];
const btScalar ima = n.m_im;
const btScalar imb = body->getInvMass();
btVector3 nrm;
const btCollisionShape* shp = body->getCollisionShape();
const btTransform& wtr = body->getWorldTransform();
btScalar dst =
m_worldInfo->m_sparsesdf.Evaluate(
wtr.invXform(m_nodes[node].m_x),
shp,
nrm,
0);
c.m_cti.m_colObj = body;
c.m_cti.m_normal = wtr.getBasis() * nrm;
c.m_cti.m_offset = dst;
c.m_node = &m_nodes[node];
const btScalar fc = m_cfg.kDF * body->getFriction();
c.m_c2 = ima;
c.m_c3 = fc;
c.m_c4 = body->isStaticOrKinematicObject() ? m_cfg.kKHR : m_cfg.kCHR;
static const btMatrix3x3 iwiStatic(0, 0, 0, 0, 0, 0, 0, 0, 0);
const btMatrix3x3& iwi = body->getInvInertiaTensorWorld();
const btVector3 ra = n.m_x - wtr.getOrigin();
c.m_c0 = ImpulseMatrix(1, ima, imb, iwi, ra);
c.m_c1 = ra;
c.m_local = body->getWorldTransform().inverse() * m_nodes[node].m_x;
m_deformableAnchors.push_back(c);
}
//
void btSoftBody::appendLinearJoint(const LJoint::Specs& specs, Cluster* body0, Body body1)
{

8
src/BulletSoftBody/btSoftBody.h
View File

@@ -354,6 +354,12 @@ public:
Node* m_node; // Owner node
};
class DeformableNodeRigidAnchor : public DeformableNodeRigidContact
{
public:
btVector3 m_local; // Anchor position in body space
};
class DeformableFaceRigidContact : public DeformableRigidContact
{
public:
@@ -774,6 +780,7 @@ public:
btAlignedObjectArray<TetraScratch> m_tetraScratches;
btAlignedObjectArray<TetraScratch> m_tetraScratchesTn;
tAnchorArray m_anchors; // Anchors
btAlignedObjectArray<DeformableNodeRigidAnchor> m_deformableAnchors;
tRContactArray m_rcontacts; // Rigid contacts
btAlignedObjectArray<DeformableNodeRigidContact> m_nodeRigidContacts;
btAlignedObjectArray<DeformableFaceNodeContact> m_faceNodeContacts;
@@ -897,6 +904,7 @@ public:
Material* mat = 0);
/* Append anchor */
void appendDeformableAnchor(int node, btRigidBody* body);
void appendAnchor(int node,
btRigidBody* body, bool disableCollisionBetweenLinkedBodies = false, btScalar influence = 1);
void appendAnchor(int node, btRigidBody* body, const btVector3& localPivot, bool disableCollisionBetweenLinkedBodies = false, btScalar influence = 1);