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add initial impulse

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This commit is contained in:
jingyuc
2021-07-18 00:52:13 -04:00
parent c24f2a72ef
commit 4119d8812e
3 changed files with 58 additions and 85 deletions
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97
examples/ReducedDeformableDemo/BasicTest.cpp
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@@ -40,10 +40,10 @@ class BasicTest : public CommonDeformableBodyBase
typedef btAlignedObjectArray<btSoftBody::Node> tNodeArray;
// btDeformableLinearElasticityForce* m_linearElasticity;
btDeformableMassSpringForce* m_massSpring;
// btDeformableMassSpringForce* m_massSpring;
static const unsigned int m_startMode = 6; // actual mode# should +1
static const unsigned int m_nReduced = 1;
static const unsigned int m_nReduced = 2;
static const unsigned int selected_mode = 0;
unsigned int m_nFull;
btScalar sim_time;
@@ -55,13 +55,10 @@ class BasicTest : public CommonDeformableBodyBase
btAssert(psb->m_reducedDofs.size() == m_nReduced);
for (int j = 0; j < m_nReduced; ++j)
{
psb->m_reducedDofs[j] = 0;
for (int i = 0; i < m_nFull; ++i)
for (int k = 0; k < 3; ++k)
{
int idx_f = 3 * i + k;
psb->m_reducedDofs[j] = psb->m_modes[j][idx_f] * (psb->m_nodes[i].m_x[k] - psb->m_x0[idx_f]);
// psb->m_reducedVelocity[j] = psb->m_modes[j][idx_f] * psb->m_nodes[i].m_v[k];
}
psb->m_reducedDofs[j] += psb->m_modes[j][3 * i + k] * (psb->m_nodes[i].m_x[k] - psb->m_x0[3 * i + k]);
}
}
@@ -69,16 +66,21 @@ class BasicTest : public CommonDeformableBodyBase
void mapToFullDofs(btSoftBody* psb)
{
btAssert(psb->m_nodes.size() == m_nFull);
for (int j = 0; j < m_nReduced; ++j)
btAlignedObjectArray<btVector3> delta_x;
delta_x.resize(m_nFull);
for (int i = 0; i < m_nFull; ++i)
{
for (int i = 0; i < m_nFull; ++i)
for (int k = 0; k < 3; ++k)
{
int idx_f = 3 * i + k;
psb->m_nodes[i].m_x[k] = psb->m_x0[idx_f] + psb->m_modes[j][idx_f] * psb->m_reducedDofs[j];
// psb->m_nodes[i].m_v[k] = psb->m_modes[j][idx_f] * psb->m_reducedVelocity[j];
}
for (int k = 0; k < 3; ++k)
{
// compute displacement
delta_x[i][k] = 0;
for (int j = 0; j < m_nReduced; ++j)
delta_x[i][k] += psb->m_modes[j][3 * i + k] * psb->m_reducedDofs[j];
// get new coordinates
psb->m_nodes[i].m_x[k] = psb->m_x0[3 * i + k] + delta_x[i][k];
}
}
}
// get deformed shape
@@ -93,7 +95,6 @@ public:
BasicTest(struct GUIHelperInterface* helper)
: CommonDeformableBodyBase(helper)
{
m_massSpring = nullptr;
m_nFull = 0;
sim_time = 0;
first_step = true;
@@ -137,7 +138,7 @@ public:
// TODO: remove this. very hacky way of adding initial deformation
if (first_step && !psb->m_bUpdateRtCst)
{
getDeformedShape(psb, 0, 100);
// getDeformedShape(psb, 0, 0.5);
first_step = false;
mapToReducedDofs(psb);
// std::cout << psb->m_reducedDofs[0] << "\n";
@@ -192,7 +193,7 @@ void BasicTest::initPhysics()
m_solver = sol;
m_dynamicsWorld = new btDeformableMultiBodyDynamicsWorld(m_dispatcher, m_broadphase, sol, m_collisionConfiguration, deformableBodySolver);
btVector3 gravity = btVector3(0, 0, 0);
btVector3 gravity = btVector3(0, -10, 0);
m_dynamicsWorld->setGravity(gravity);
m_guiHelper->createPhysicsDebugDrawer(m_dynamicsWorld);
@@ -216,56 +217,18 @@ void BasicTest::initPhysics()
std::string modes_file("../../../examples/SoftDemo/modes.bin");
btSoftBodyHelpers::readBinaryModes(psb->m_modes, m_startMode, m_nReduced, 3 * m_nFull, modes_file.c_str()); // default to 3D
// std::string Kr_dense_file("../../../examples/SoftDemo/Kr_dense.bin");
// btSoftBodyHelpers::readBinaryMat(psb->m_KrDense, m_startMode, m_nReduced, 3 * m_nFull, Kr_dense_file.c_str());
// std::string Mr_dense_file("../../../examples/SoftDemo/Mr_dense.bin");
// btSoftBodyHelpers::readBinaryMat(psb->m_MrDense, m_startMode, m_nReduced, 3 * m_nFull, Mr_dense_file.c_str());
// for (int i = 0; i < 3*m_nFull; ++i)
// std::cout << psb->m_modes[0][i] << '\n';
// std::string M_file("../../../examples/SoftDemo/M_diag_mat.bin");
// btSoftBodyHelpers::readBinary(psb->m_M, buffer_n_modes, M_file.c_str());
// get rest position
psb->m_x0.resize(3 * psb->m_nodes.size());
for (int i = 0; i < psb->m_nodes.size(); ++i)
for (int k = 0; k < 3; ++k)
psb->m_x0[3 * i + k] = psb->m_nodes[i].m_x[k];
// btAlignedObjectArray<btAlignedObjectArray<btScalar> > M_red;
// M_red.resize(m_nReduced);
// for (int i = 0; i < m_nReduced; ++i) {
// M_red.resize(m_nReduced);
// }
// for (int i = 0; i < m_nFull; ++i) {
// for (int j = 0; j < m_nReduced; ++j) {
// for (int k = 0; k < m_nFull; ++k) {
// for (int l = 0; l < m_nReduced; ++l) {
// btScalar tmp = psb->m_modes[i][j] * psb->m_M[i] * psb->m_modes[k][l];
// std::cout << tmp << '\n';
// }
// }
// }
// }
// std::ofstream outfile1("before_map.txt");
// for (int i = 0; i < psb->m_nodes.size(); ++i) {
// for (int k = 0; k < 3; ++k)
// outfile1 << psb->m_nodes[i].m_x[k] << '\n';
// }
// outfile1.close();
// mapToFullDofs(psb->m_modes, psb->m_reducedNodes, psb->m_reducedVelocity, psb->m_nodes);
// std::ofstream outfile2("after_map.txt");
// for (int i = 0; i < psb->m_nodes.size(); ++i) {
// for (int k = 0; k < 3; ++k)
// outfile2 << psb->m_nodes[i].m_x[k] << '\n';
// }
// outfile2.close();
std::ofstream outfile1("before_map.txt");
for (int i = 0; i < psb->m_nodes.size(); ++i) {
for (int k = 0; k < 3; ++k)
outfile1 << psb->m_nodes[i].m_x[k] << '\n';
}
outfile1.close();
getDeformableDynamicsWorld()->addSoftBody(psb);
psb->scale(btVector3(2, 2, 2));
@@ -281,14 +244,10 @@ void BasicTest::initPhysics()
btSoftBodyHelpers::generateBoundaryFaces(psb);
psb->setVelocity(btVector3(0, -COLLIDING_VELOCITY, 0));
// btDeformableLinearElasticityForce* linearElasticity = new btDeformableLinearElasticityForce(100,100,0.01);
// m_linearElasticity = linearElasticity;
m_massSpring = new btDeformableMassSpringForce(10.0, 0.0); //TODO: this stiffness needs to match the modes
getDeformableDynamicsWorld()->addForce(psb, m_massSpring);
m_forces.push_back(m_massSpring);
btDeformableGravityForce* gravity_force = new btDeformableGravityForce(gravity);
getDeformableDynamicsWorld()->addForce(psb, gravity_force);
m_forces.push_back(gravity_force);
}
getDeformableDynamicsWorld()->setImplicit(false);
getDeformableDynamicsWorld()->setLineSearch(false);