add extreme deformation demo

examples/DeformableDemo/LargeDeformation.cpp

@@ -0,0 +1,226 @@
+/*
+ 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 "LargeDeformation.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 "../CommonInterfaces/CommonParameterInterface.h"
+#include <stdio.h>  //printf debugging
+
+#include "../CommonInterfaces/CommonDeformableBodyBase.h"
+#include "../Utils/b3ResourcePath.h"
+
+///The LargeDeformation shows the contact between volumetric deformable objects and rigid objects.
+static btScalar E = 25;
+static btScalar nu = 0.3;
+static btScalar damping = 0.01;
+
+struct TetraCube
+{
+#include "../SoftDemo/cube.inl"
+};
+
+class LargeDeformation : public CommonDeformableBodyBase
+{
+	btDeformableLinearElasticityForce* m_linearElasticity;
+
+public:
+	LargeDeformation(struct GUIHelperInterface* helper)
+		: CommonDeformableBodyBase(helper)
+	{
+        m_linearElasticity = 0;
+	}
+	virtual ~LargeDeformation()
+	{
+	}
+	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)
+    {
+		m_linearElasticity->setPoissonRatio(nu);
+		m_linearElasticity->setYoungsModulus(E);
+		m_linearElasticity->setDamping(damping);
+        float internalTimeStep = 1. / 60.f;
+        m_dynamicsWorld->stepSimulation(deltaTime, 1, internalTimeStep);
+    }
+    
+    virtual void renderScene()
+    {
+        CommonDeformableBodyBase::renderScene();
+        btDeformableMultiBodyDynamicsWorld* deformableWorld = getDeformableDynamicsWorld();
+        
+        for (int i = 0; i < deformableWorld->getSoftBodyArray().size(); i++)
+        {
+            btSoftBody* psb = (btSoftBody*)deformableWorld->getSoftBodyArray()[i];
+            {
+                btSoftBodyHelpers::DrawFrame(psb, deformableWorld->getDebugDrawer());
+                btSoftBodyHelpers::Draw(psb, deformableWorld->getDebugDrawer(), deformableWorld->getDrawFlags());
+            }
+        }
+    }
+};
+
+void LargeDeformation::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();
+
+	btDeformableMultiBodyConstraintSolver* sol = new btDeformableMultiBodyConstraintSolver();
+    sol->setDeformableSolver(deformableBodySolver);
+	m_solver = sol;
+
+	m_dynamicsWorld = new btDeformableMultiBodyDynamicsWorld(m_dispatcher, m_broadphase, sol, m_collisionConfiguration, deformableBodySolver);
+	m_guiHelper->createPhysicsDebugDrawer(m_dynamicsWorld);
+
+    // create volumetric soft body
+    {
+        btSoftBody* psb = btSoftBodyHelpers::CreateFromTetGenData(getDeformableDynamicsWorld()->getWorldInfo(),
+                                                                  TetraCube::getElements(),
+                                                                  0,
+                                                                  TetraCube::getNodes(),
+                                                                  false, true, true);
+        getDeformableDynamicsWorld()->addSoftBody(psb);
+        psb->scale(btVector3(2, 2, 2));
+        psb->translate(btVector3(0, 5, 0));
+        psb->getCollisionShape()->setMargin(0.1);
+        psb->setTotalMass(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 = 0.5;
+        psb->m_cfg.collisions = btSoftBody::fCollision::SDF_RD;
+        psb->m_cfg.collisions |= btSoftBody::fCollision::SDF_RDN;
+		psb->m_sleepingThreshold = 0;
+        btSoftBodyHelpers::generateBoundaryFaces(psb);
+		for (int i = 0; i < psb->m_nodes.size(); ++i)
+		{
+			for (int j = 0; j < 3; ++j)
+				psb->m_nodes[i].m_x[j] = ((double) 2*rand() / (RAND_MAX))-1.0;
+			psb->m_nodes[i].m_x[1]+=8;
+		}
+        
+        btDeformableLinearElasticityForce* linearElasticity = new btDeformableLinearElasticityForce(100,100,0.01);
+		m_linearElasticity = linearElasticity;
+        getDeformableDynamicsWorld()->addForce(psb, linearElasticity);
+        m_forces.push_back(linearElasticity);
+    }
+    getDeformableDynamicsWorld()->setImplicit(true);
+    getDeformableDynamicsWorld()->setLineSearch(false);
+    getDeformableDynamicsWorld()->setUseProjection(true);
+    getDeformableDynamicsWorld()->getSolverInfo().m_deformable_erp = 0.1;
+    getDeformableDynamicsWorld()->getSolverInfo().m_deformable_maxErrorReduction = btScalar(20);
+    getDeformableDynamicsWorld()->getSolverInfo().m_leastSquaresResidualThreshold = 1e-3;
+    getDeformableDynamicsWorld()->getSolverInfo().m_splitImpulse = true;
+    getDeformableDynamicsWorld()->getSolverInfo().m_numIterations = 100;
+    // add a few rigid bodies
+	m_guiHelper->autogenerateGraphicsObjects(m_dynamicsWorld);
+	
+	{
+		SliderParams slider("Young's Modulus", &E);
+		slider.m_minVal = 0;
+		slider.m_maxVal = 200;
+		if (m_guiHelper->getParameterInterface())
+			m_guiHelper->getParameterInterface()->registerSliderFloatParameter(slider);
+	}
+	{
+		SliderParams slider("Poisson Ratio", &nu);
+		slider.m_minVal = 0.05;
+		slider.m_maxVal = 0.40;
+		if (m_guiHelper->getParameterInterface())
+			m_guiHelper->getParameterInterface()->registerSliderFloatParameter(slider);
+	}
+	{
+		SliderParams slider("Damping", &damping);
+		slider.m_minVal = 0.001;
+		slider.m_maxVal = 0.01;
+		if (m_guiHelper->getParameterInterface())
+			m_guiHelper->getParameterInterface()->registerSliderFloatParameter(slider);
+	}
+}
+
+void LargeDeformation::exitPhysics()
+{
+	//cleanup in the reverse order of creation/initialization
+    removePickingConstraint();
+	//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* LargeDeformationCreateFunc(struct CommonExampleOptions& options)
+{
+	return new LargeDeformation(options.m_guiHelper);
+}
+
+

examples/DeformableDemo/LargeDeformation.h

@@ -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 _LARGE_DEFORMATION_H
+#define _LARGE_DEFORMATION_H
+
+class CommonExampleInterface* LargeDeformationCreateFunc(struct CommonExampleOptions& options);
+
+#endif  //_LARGE_DEFORMATION_H

examples/DeformableDemo/VolumetricDeformable.cpp

@@ -100,7 +100,7 @@ public:
     
     void Ctor_RbUpStack(int count)
     {
-        float mass = 0.2;
+        float mass = 2;
         
         btCompoundShape* cylinderCompound = new btCompoundShape;
         btCollisionShape* cylinderShape = new btCylinderShapeX(btVector3(2, .5, .5));
@@ -212,18 +212,16 @@ void VolumetricDeformable::initPhysics()
         psb->setTotalMass(0.5);
         psb->m_cfg.kKHR = 1; // collision hardness with kinematic objects
         psb->m_cfg.kCHR = 1; // collision hardness with rigid body
-        psb->m_cfg.kDF = 0.5;
+		psb->m_cfg.kDF = 0.5;
         psb->m_cfg.collisions = btSoftBody::fCollision::SDF_RD;
-//        psb->m_cfg.collisions |= btSoftBody::fCollision::SDF_RDF;
         psb->m_cfg.collisions |= btSoftBody::fCollision::SDF_RDN;
 		psb->m_sleepingThreshold = 0;
         btSoftBodyHelpers::generateBoundaryFaces(psb);
-        
         btDeformableGravityForce* gravity_force =  new btDeformableGravityForce(gravity);
         getDeformableDynamicsWorld()->addForce(psb, gravity_force);
         m_forces.push_back(gravity_force);
         
-        btDeformableLinearElasticityForce* linearElasticity = new btDeformableLinearElasticityForce(1000,1000,0.01);
+        btDeformableLinearElasticityForce* linearElasticity = new btDeformableLinearElasticityForce(100,100,0.01);
 		m_linearElasticity = linearElasticity;
         getDeformableDynamicsWorld()->addForce(psb, linearElasticity);
         m_forces.push_back(linearElasticity);
@@ -231,6 +229,11 @@ void VolumetricDeformable::initPhysics()
     getDeformableDynamicsWorld()->setImplicit(true);
     getDeformableDynamicsWorld()->setLineSearch(false);
     getDeformableDynamicsWorld()->setUseProjection(true);
+    getDeformableDynamicsWorld()->getSolverInfo().m_deformable_erp = 0.1;
+    getDeformableDynamicsWorld()->getSolverInfo().m_deformable_maxErrorReduction = btScalar(20);
+    getDeformableDynamicsWorld()->getSolverInfo().m_leastSquaresResidualThreshold = 1e-3;
+    getDeformableDynamicsWorld()->getSolverInfo().m_splitImpulse = true;
+    getDeformableDynamicsWorld()->getSolverInfo().m_numIterations = 100;
     // add a few rigid bodies
     Ctor_RbUpStack(4);
 	m_guiHelper->autogenerateGraphicsObjects(m_dynamicsWorld);
@@ -238,21 +241,21 @@ void VolumetricDeformable::initPhysics()
 	{
 		SliderParams slider("Young's Modulus", &E);
 		slider.m_minVal = 0;
-		slider.m_maxVal = 50;
+		slider.m_maxVal = 200;
 		if (m_guiHelper->getParameterInterface())
 			m_guiHelper->getParameterInterface()->registerSliderFloatParameter(slider);
 	}
 	{
 		SliderParams slider("Poisson Ratio", &nu);
 		slider.m_minVal = 0.05;
-		slider.m_maxVal = 0.40;
+		slider.m_maxVal = 0.49;
 		if (m_guiHelper->getParameterInterface())
 			m_guiHelper->getParameterInterface()->registerSliderFloatParameter(slider);
 	}
 	{
 		SliderParams slider("Damping", &damping);
 		slider.m_minVal = 0.001;
-		slider.m_maxVal = 0.02;
+		slider.m_maxVal = 0.01;
 		if (m_guiHelper->getParameterInterface())
 			m_guiHelper->getParameterInterface()->registerSliderFloatParameter(slider);
 	}

examples/ExampleBrowser/CMakeLists.txt

@@ -373,6 +373,8 @@ SET(BulletExampleBrowser_SRCS
   ../DeformableDemo/SplitImpulse.h
   ../DeformableDemo/VolumetricDeformable.cpp
   ../DeformableDemo/VolumetricDeformable.h
+  ../DeformableDemo/LargeDeformation.cpp
+  ../DeformableDemo/LargeDeformation.h
   ../DeformableDemo/DeformableClothAnchor.cpp
   ../DeformableDemo/DeformableClothAnchor.h
   ../DeformableDemo/MultibodyClothAnchor.cpp

examples/ExampleBrowser/ExampleEntries.cpp

@@ -52,6 +52,7 @@
 #include "../DeformableDemo/PinchFriction.h"
 #include "../DeformableDemo/DeformableMultibody.h"
 #include "../DeformableDemo/VolumetricDeformable.h"
+#include "../DeformableDemo/LargeDeformation.h"
 #include "../DeformableDemo/GraspDeformable.h"
 #include "../DeformableDemo/DeformableContact.h"
 #include "../DeformableDemo/DeformableClothAnchor.h"
@@ -202,6 +203,7 @@ 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, "Extreme Deformation", "Recovery from extreme deformation", LargeDeformationCreateFunc),
         ExampleEntry(1, "Rigid Cloth Anchor", "Deformable Rigid body Anchor test", DeformableClothAnchorCreateFunc),
         ExampleEntry(1, "Multibody Cloth Anchor", "Deformable Multibody Anchor test", MultibodyClothAnchorCreateFunc),
         ExampleEntry(1, "Deformable-MultiBody Contact", "MultiBody and Deformable contact", DeformableMultibodyCreateFunc),