code clean up

examples/DeformableDemo/DeformableRigid.cpp

@@ -232,7 +232,7 @@ void DeformableRigid::initPhysics()
         psb->setDampingCoefficient(0.05);
         psb->m_cfg.kKHR = 1; // collision hardness with kinematic objects
         psb->m_cfg.kCHR = 1; // collision hardness with rigid body
-        psb->m_cfg.kDF = 0;
+        psb->m_cfg.kDF = 1;
         psb->m_cfg.collisions = btSoftBody::fCollision::SDF_RD;
         getDeformableDynamicsWorld()->addSoftBody(psb);
         getDeformableDynamicsWorld()->addForce(psb, new btDeformableMassSpringForce());

examples/DeformableDemo/GraspDeformable.cpp

@@ -331,10 +331,10 @@ void GraspDeformable::initPhysics()
         psb->getCollisionShape()->setMargin(0.1);
         psb->setTotalMass(1);
         psb->setSpringStiffness(0);
-        psb->setDampingCoefficient(0.02);
+        psb->setDampingCoefficient(0.1);
         psb->m_cfg.kKHR = 1; // collision hardness with kinematic objects
         psb->m_cfg.kCHR = 1; // collision hardness with rigid body
-        psb->m_cfg.kDF = 0;
+        psb->m_cfg.kDF = 2;
         psb->m_cfg.collisions = btSoftBody::fCollision::SDF_RD;
         getDeformableDynamicsWorld()->addSoftBody(psb);
         getDeformableDynamicsWorld()->addForce(psb, new btDeformableMassSpringForce());

examples/DeformableDemo/VolumetricDeformable.cpp

@@ -234,7 +234,7 @@ void VolumetricDeformable::initPhysics()
         psb->getCollisionShape()->setMargin(0.25);
 //        psb->generateBendingConstraints(2);
         psb->setTotalMass(1);
-        psb->setSpringStiffness(1);
+        psb->setSpringStiffness(0);
         psb->setDampingCoefficient(0.01);
         psb->m_cfg.kKHR = 1; // collision hardness with kinematic objects
         psb->m_cfg.kCHR = 1; // collision hardness with rigid body
@@ -242,6 +242,7 @@ void VolumetricDeformable::initPhysics()
         psb->m_cfg.collisions = btSoftBody::fCollision::SDF_RD;
         getDeformableDynamicsWorld()->addForce(psb, new btDeformableMassSpringForce());
         getDeformableDynamicsWorld()->addForce(psb, new btDeformableGravityForce(gravity));
+        getDeformableDynamicsWorld()->addForce(psb, new btDeformableCorotatedForce(.5,.5));
     }
     // add a few rigid bodies
     Ctor_RbUpStack(4); 

src/BulletSoftBody/btCGProjection.h

@@ -53,49 +53,6 @@ struct DeformableContactConstraint
     }
 };
 
-struct DeformableFrictionConstraint
-{
-    btAlignedObjectArray<bool> m_static; // whether the friction is static
-    btAlignedObjectArray<btScalar> m_impulse; // the impulse magnitude the node feels
-    btAlignedObjectArray<btScalar> m_dv;      // the dv magnitude of the node
-    btAlignedObjectArray<btVector3> m_direction; // the direction of the friction for the node
-    
-    
-    btAlignedObjectArray<bool> m_static_prev;
-    btAlignedObjectArray<btScalar> m_impulse_prev;
-    btAlignedObjectArray<btScalar> m_dv_prev;
-    btAlignedObjectArray<btVector3> m_direction_prev;
-    
-    btAlignedObjectArray<bool> m_released; // whether the contact is released
-
-    
-    // the total impulse the node applied to the rb in the tangential direction in the cg solve
-    btAlignedObjectArray<btVector3> m_accumulated_tangent_impulse;
-    
-    DeformableFrictionConstraint()
-    {
-        append();
-    }
-    
-    void append()
-    {
-        m_static.push_back(false);
-        m_static_prev.push_back(false);
-        
-        m_direction_prev.push_back(btVector3(0,0,0));
-        m_direction.push_back(btVector3(0,0,0));
-        
-        m_impulse.push_back(0);
-        m_impulse_prev.push_back(0);
-        
-        m_dv.push_back(0);
-        m_dv_prev.push_back(0);
-        
-        m_accumulated_tangent_impulse.push_back(btVector3(0,0,0));
-        m_released.push_back(false);
-    }
-};
-
 class btCGProjection
 {
 public:
@@ -104,7 +61,6 @@ public:
     typedef btAlignedObjectArray<btAlignedObjectArray<btScalar> > TArrayStack;
     btAlignedObjectArray<btSoftBody *>& m_softBodies;
     btDeformableRigidDynamicsWorld* m_world;
-//    const btAlignedObjectArray<btSoftBody::Node*>* m_nodes;
     const btScalar& m_dt;
     
     btCGProjection(btAlignedObjectArray<btSoftBody *>& softBodies, const btScalar& dt)

src/BulletSoftBody/btDeformableBodySolver.cpp

@@ -19,6 +19,7 @@
 btDeformableBodySolver::btDeformableBodySolver()
 : m_numNodes(0)
 , m_cg(10)
+, m_contact_iterations(10)
 {
     m_objective = new btDeformableBackwardEulerObjective(m_softBodySet, m_backupVelocity);
 }
@@ -46,7 +47,7 @@ void btDeformableBodySolver::solveConstraints(float solverdt)
 void btDeformableBodySolver::computeStep(TVStack& dv, const TVStack& residual)
 {
     
-    btScalar tolerance = std::numeric_limits<float>::epsilon() * m_objective->computeNorm(residual);
+    btScalar tolerance = std::numeric_limits<float>::epsilon() * 1024 * m_objective->computeNorm(residual);
     m_cg.solve(*m_objective, dv, residual, tolerance);
 }
 
@@ -76,7 +77,7 @@ void btDeformableBodySolver::setConstraints()
 {
     BT_PROFILE("setConstraint");
     m_objective->setConstraints();
-    for (int i = 0; i < 10; ++i)
+    for (int i = 0; i < m_contact_iterations; ++i)
     {
         m_objective->projection.update();
         m_objective->enforceConstraint(m_dv);

src/BulletSoftBody/btDeformableBodySolver.h

@@ -37,6 +37,7 @@ protected:
    
     btAlignedObjectArray<btVector3> m_backupVelocity;
     btScalar m_dt;
+    btScalar m_contact_iterations;
     btConjugateGradient<btDeformableBackwardEulerObjective> m_cg;