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clean up initialzation

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This commit is contained in:
jyc-n
2021-07-26 15:30:35 -04:00
parent 9baee29300
commit 7678545e76
6 changed files with 136 additions and 114 deletions
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95
examples/ReducedDeformableDemo/BasicTest.cpp
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@@ -37,54 +37,9 @@ static btScalar COLLIDING_VELOCITY = 0;
class BasicTest : public CommonDeformableBodyBase
{
typedef btAlignedObjectArray<btSoftBody::Node> tNodeArray;
// btDeformableLinearElasticityForce* m_linearElasticity;
// btDeformableMassSpringForce* m_massSpring;
static const unsigned int m_startMode = 6; // actual mode# should +1
static const unsigned int m_nReduced = 2;
static const unsigned int selected_mode = 0;
unsigned int m_nFull;
btScalar sim_time;
bool first_step;
// compute reduced degree of freedoms
void mapToReducedDofs(btReducedSoftBody* rsb)
{
btAssert(rsb->m_reducedDofs.size() == m_nReduced);
for (int j = 0; j < m_nReduced; ++j)
{
rsb->m_reducedDofs[j] = 0;
for (int i = 0; i < m_nFull; ++i)
for (int k = 0; k < 3; ++k)
rsb->m_reducedDofs[j] += rsb->m_modes[j][3 * i + k] * (rsb->m_nodes[i].m_x[k] - rsb->m_x0[3 * i + k]);
}
}
// compute full degree of freedoms
void mapToFullDofs(btReducedSoftBody* rsb)
{
btAssert(rsb->m_nodes.size() == m_nFull);
btAlignedObjectArray<btVector3> delta_x;
delta_x.resize(m_nFull);
btVector3 origin = rsb->getWorldTransform().getOrigin();
for (int i = 0; i < m_nFull; ++i)
{
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] += rsb->m_modes[j][3 * i + k] * rsb->m_reducedDofs[j];
// get new coordinates
rsb->m_nodes[i].m_x[k] = rsb->m_x0[3 * i + k] + delta_x[i][k] + origin[k]; //TODO: assume the initial origin is at (0,0,0)
}
}
}
// get deformed shape
void getDeformedShape(btReducedSoftBody* rsb, const int mode_n, const btScalar scale = 1)
{
@@ -97,7 +52,6 @@ public:
BasicTest(struct GUIHelperInterface* helper)
: CommonDeformableBodyBase(helper)
{
m_nFull = 0;
sim_time = 0;
first_step = true;
}
@@ -142,13 +96,11 @@ public:
{
// getDeformedShape(rsb, 0, 0.5);
first_step = false;
mapToReducedDofs(rsb);
rsb->updateReducedDofs();
// std::cout << rsb->m_reducedDofs[0] << "\n";
}
// compute reduced dofs
rsb->m_reducedDofs.resize(m_nReduced);
rsb->m_reducedVelocity.resize(m_nReduced);
sim_time += deltaTime;
// std::cout << rsb->m_eigenvalues[0] << "\t" << sim_time << "\t" << deltaTime << "\t" << sin(rsb->m_eigenvalues[0] * sim_time) << "\n";
@@ -158,7 +110,7 @@ public:
// m_dynamicsWorld->stepSimulation(1, 1, internalTimeStep);
// map reduced dof back to full
mapToFullDofs(rsb);
rsb->updateFullDofs();
}
virtual void renderScene()
@@ -200,30 +152,13 @@ void BasicTest::initPhysics()
m_guiHelper->createPhysicsDebugDrawer(m_dynamicsWorld);
// create volumetric soft body
{
std::string filename("../../../examples/SoftDemo/mesh.vtk");
btReducedSoftBody* rsb = btReducedSoftBodyHelpers::CreateFromVtkFile(getDeformableDynamicsWorld()->getWorldInfo(), filename.c_str());
m_nFull = rsb->m_nodes.size();
rsb->m_reducedModel = true;
// read in eigenmodes, stiffness and mass matrices
std::string eigenvalues_file("../../../examples/SoftDemo/eigenvalues.bin");
btReducedSoftBodyHelpers::readBinary(rsb->m_eigenvalues, m_startMode, m_nReduced, 3 * m_nFull, eigenvalues_file.c_str());
std::string Kr_file("../../../examples/SoftDemo/K_r_diag_mat.bin");
btReducedSoftBodyHelpers::readBinary(rsb->m_Kr, m_startMode, m_nReduced, 3 * m_nFull, Kr_file.c_str());
std::string Mr_file("../../../examples/SoftDemo/M_r_diag_mat.bin");
btReducedSoftBodyHelpers::readBinary(rsb->m_Mr, m_startMode, m_nReduced, 3 * m_nFull, Mr_file.c_str());
std::string modes_file("../../../examples/SoftDemo/modes.bin");
btReducedSoftBodyHelpers::readBinaryModes(rsb->m_modes, m_startMode, m_nReduced, 3 * m_nFull, modes_file.c_str()); // default to 3D
// get rest position
rsb->m_x0.resize(3 * rsb->m_nodes.size());
for (int i = 0; i < rsb->m_nodes.size(); ++i)
for (int k = 0; k < 3; ++k)
rsb->m_x0[3 * i + k] = rsb->m_nodes[i].m_x[k];
{
std::string filepath("../../../examples/SoftDemo/");
std::string filename = filepath + "mesh.vtk";
btReducedSoftBody* rsb = btReducedSoftBodyHelpers::createFromVtkFile(getDeformableDynamicsWorld()->getWorldInfo(), filename.c_str());
rsb->setReducedModes(6, 2, rsb->m_nodes.size());
btReducedSoftBodyHelpers::readReducedDeformableInfoFromFiles(rsb, filepath.c_str());
getDeformableDynamicsWorld()->addSoftBody(rsb);
rsb->scale(btVector3(2, 2, 2));
@@ -237,18 +172,6 @@ void BasicTest::initPhysics()
rsb->m_cfg.collisions |= btSoftBody::fCollision::SDF_RDN;
rsb->m_sleepingThreshold = 0;
btSoftBodyHelpers::generateBoundaryFaces(rsb);
std::string M_file("../../../examples/SoftDemo/M_diag_mat.bin");
btAlignedObjectArray<btScalar> mass_array;
btReducedSoftBodyHelpers::readBinary(mass_array, 0, 3 * m_nFull, 3 * m_nFull, M_file.c_str());
// assign mass to nodes
btScalar mass = 0;
for (int i = 0; i < rsb->m_nodes.size(); ++i)
{
rsb->m_nodes[i].m_im = mass_array[3 * i]; // here we use m_im as the actual mass not the mass inverse
mass += mass_array[3 * i];
}
rsb->setMass(mass);
rsb->setVelocity(btVector3(0, -COLLIDING_VELOCITY, 0));