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add support for deformable vs. deformable contact

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Xuchen Han
2019-09-16 16:03:36 -07:00
parent 403eb62dfa
commit 1bfb226be8
12 changed files with 426 additions and 76 deletions
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126
src/BulletSoftBody/btDeformableContactProjection.cpp
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@@ -35,7 +35,7 @@ btScalar btDeformableContactProjection::update()
// face constraints
for (int index = 0; index < m_allFaceConstraints.size(); ++index)
{
btDeformableFaceRigidContactConstraint* constraint = m_allFaceConstraints[index];
btDeformableContactConstraint* constraint = m_allFaceConstraints[index];
btScalar localResidualSquare = constraint->solveConstraint();
residualSquare = btMax(residualSquare, localResidualSquare);
}
@@ -140,66 +140,64 @@ void btDeformableContactProjection::setConstraints()
delete constraint;
}
}
}
// todo xuchenhan@: set Deformable Face vs. Deformable Node
}
void btDeformableContactProjection::enforceConstraint(TVStack& x)
{
// x is set to zero when passed in
// loop through node constraints to add in contributions to dv
for (int index = 0; index < m_nodeRigidConstraints.size(); ++index)
{
btAlignedObjectArray<btDeformableNodeRigidContactConstraint>& constraintsList = *m_nodeRigidConstraints.getAtIndex(index);
// i is node index
int i = m_nodeRigidConstraints.getKeyAtIndex(index).getUid1();
int numConstraints = 1;
// int numConstraints = constraintsList.size();
// if (m_faceRigidConstraints.find(i) != NULL)
// {
// numConstraints += m_faceRigidConstraints[i]->size();
// }
for (int j = 0; j < constraintsList.size(); ++j)
// set Deformable Face vs. Deformable Node constraint
for (int j = 0; j < psb->m_faceNodeContacts.size(); ++j)
{
const btDeformableNodeRigidContactConstraint& constraint = constraintsList[j];
x[i] += constraint.getDv(constraint.getContact()->m_node)/btScalar(numConstraints);
}
}
// loop through face constraints to add in contributions to dv
// note that for each face constraint is owned by three nodes. Be careful here to only add the dv to the node that owns the constraint
for (int index = 0; index < m_faceRigidConstraints.size(); ++index)
{
btAlignedObjectArray<btDeformableFaceRigidContactConstraint*>& constraintsList = *m_faceRigidConstraints.getAtIndex(index);
// i is node index
int i = m_faceRigidConstraints.getKeyAtIndex(index).getUid1();
for (int j = 0; j < constraintsList.size(); ++j)
{
const btDeformableFaceRigidContactConstraint* constraint = constraintsList[j];
const btSoftBody::Face* face = constraint->m_face;
btSoftBody::Node* node;
// find the node that owns the constraint
for (int k = 0; k < 3; ++k)
const btSoftBody::DeformableFaceNodeContact& contact = psb->m_faceNodeContacts[j];
btDeformableFaceNodeContactConstraint* constraint = new btDeformableFaceNodeContactConstraint(contact);
btVector3 va = constraint->getVa();
btVector3 vb = constraint->getVb();
const btVector3 vr = vb - va;
const btScalar dn = btDot(vr, contact.m_normal);
if (dn > -SIMD_EPSILON)
{
if (face->m_n[k]->index == i)
btSoftBody::Node* node = contact.m_node;
btSoftBody::Face* face = contact.m_face;
m_allFaceConstraints.push_back(constraint);
if (node->m_im != 0)
{
node = face->m_n[k];
break;
if (m_deformableConstraints.find(node->index) == NULL)
{
btAlignedObjectArray<btDeformableFaceNodeContactConstraint*> constraintsList;
constraintsList.push_back(constraint);
m_deformableConstraints.insert(node->index, constraintsList);
}
else
{
btAlignedObjectArray<btDeformableFaceNodeContactConstraint*>& constraintsList = *m_deformableConstraints[node->index];
constraintsList.push_back(constraint);
}
}
// add face constraints to each of the nodes
for (int k = 0; k < 3; ++k)
{
btSoftBody::Node* node = face->m_n[k];
// static node does not need to own face/rigid constraint
if (node->m_im != 0)
{
if (m_deformableConstraints.find(node->index) == NULL)
{
btAlignedObjectArray<btDeformableFaceNodeContactConstraint*> constraintsList;
constraintsList.push_back(constraint);
m_deformableConstraints.insert(node->index, constraintsList);
}
else
{
btAlignedObjectArray<btDeformableFaceNodeContactConstraint*>& constraintsList = *m_deformableConstraints[node->index];
constraintsList.push_back(constraint);
}
}
}
}
x[i] += constraint->getDv(node);
else
{
delete constraint;
}
}
}
// todo xuchenhan@: add deformable deformable constraints' contribution to dv
// Finally, loop through static constraints to set dv of static nodes to zero
for (int index = 0; index < m_staticConstraints.size(); ++index)
{
const btDeformableStaticConstraint& constraint = *m_staticConstraints.getAtIndex(index);
int i = m_staticConstraints.getKeyAtIndex(index).getUid1();
x[i] = constraint.getDv(constraint.m_node);
}
}
void btDeformableContactProjection::project(TVStack& x)
@@ -258,7 +256,7 @@ void btDeformableContactProjection::setProjection()
hasConstraint = true;
}
// accumulate normals
// accumulate normals from Deformable Node vs. Rigid constraints
if (!existStaticConstraint && m_nodeRigidConstraints.find(index) != NULL)
{
hasConstraint = true;
@@ -276,6 +274,7 @@ void btDeformableContactProjection::setProjection()
}
}
// accumulate normals from Deformable Face vs. Rigid constraints
if (!existStaticConstraint && m_faceRigidConstraints.find(index) != NULL)
{
hasConstraint = true;
@@ -293,6 +292,24 @@ void btDeformableContactProjection::setProjection()
}
}
// accumulate normals from Deformable Node vs. Deformable Face constraints
if (!existStaticConstraint && m_deformableConstraints.find(index) != NULL)
{
hasConstraint = true;
btAlignedObjectArray<btDeformableFaceNodeContactConstraint*>& constraintsList = *m_deformableConstraints[index];
for (int k = 0; k < constraintsList.size(); ++k)
{
if (constraintsList[k]->m_static)
{
existStaticConstraint = true;
break;
}
const btVector3& local_normal = constraintsList[k]->m_normal;
normals.push_back(local_normal);
averagedNormal += local_normal;
}
}
// build projections
if (!hasConstraint)
@@ -388,6 +405,7 @@ void btDeformableContactProjection::reinitialize(bool nodeUpdated)
m_staticConstraints.clear();
m_nodeRigidConstraints.clear();
m_faceRigidConstraints.clear();
m_deformableConstraints.clear();
m_projectionsDict.clear();
for (int i = 0; i < m_allFaceConstraints.size(); ++i)
{