add mode visualizer example.

examples/ExampleBrowser/CMakeLists.txt

@@ -390,6 +390,8 @@ SET(BulletExampleBrowser_SRCS
   ../RigidBody/KinematicRigidBodyExample.cpp
 	../ReducedDeformableDemo/BasicTest.cpp
 	../ReducedDeformableDemo/BasicTest.h
+	../ReducedDeformableDemo/ModeVisualizer.cpp
+	../ReducedDeformableDemo/ModeVisualizer.h
   ../Constraints/TestHingeTorque.cpp
   ../Constraints/TestHingeTorque.h
   ../Constraints/ConstraintDemo.cpp

examples/ExampleBrowser/ExampleEntries.cpp

@@ -73,6 +73,7 @@
 #include "../RoboticsLearning/KukaGraspExample.h"
 #include "../RoboticsLearning/GripperGraspExample.h"
 #include "../ReducedDeformableDemo/BasicTest.h"
+#include "../ReducedDeformableDemo/ModeVisualizer.h"
 #include "../InverseKinematics/InverseKinematicsExample.h"
 
 #ifdef B3_ENABLE_TINY_AUDIO
@@ -217,6 +218,7 @@ static ExampleEntry gDefaultExamples[] =
         // ExampleEntry(1, "MultiBody Baseline", "MultiBody Baseline", MultiBodyBaselineCreateFunc),
 		
 		ExampleEntry(0, "Reduced Deformabe Body"),
+		ExampleEntry(1, "Mode Visualizer", "Visualizer the modes for reduced deformable objects", ReducedModeVisualizerCreateFunc),
 		ExampleEntry(1, "BasicRD", "Simple dynamics test for the reduced deformable objects", ReducedBasicTestCreateFunc),
 		// ExampleEntry(1, "Simple Reduced Deformable Test", "Simple dynamics test for the reduced deformable objects", ReducedBasicTestCreateFunc),
         

examples/ReducedDeformableDemo/ModeVisualizer.cpp

@@ -0,0 +1,203 @@
+/*
+ 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 "ModeVisualizer.h"
+///btBulletDynamicsCommon.h is the main Bullet include file, contains most common include files.
+#include "btBulletDynamicsCommon.h"
+#include "BulletSoftBody/btDeformableMultiBodyDynamicsWorld.h"
+#include "BulletSoftBody/BulletReducedSoftBody/btReducedSoftBody.h"
+#include "BulletSoftBody/BulletReducedSoftBody/btReducedSoftBodyHelpers.h"
+#include "BulletSoftBody/BulletReducedSoftBody/btReducedSoftBodySolver.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"
+
+
+static int start_mode = 6;
+static int num_modes = 20;
+static btScalar visualize_mode = 0;
+static btScalar frequency_scale = 1;
+
+class ModeVisualizer : public CommonDeformableBodyBase
+{
+    btScalar sim_time;
+
+    // get deformed shape
+    void getDeformedShape(btReducedSoftBody* rsb, const int mode_n, const btScalar time_term = 1)
+    {
+      for (int i = 0; i < rsb->m_nodes.size(); ++i)
+        for (int k = 0; k < 3; ++k)
+          rsb->m_nodes[i].m_x[k] = rsb->m_x0[i][k] + rsb->m_modes[mode_n][3 * i + k] * time_term;
+    }
+
+public:
+    ModeVisualizer(struct GUIHelperInterface* helper)
+        : CommonDeformableBodyBase(helper)
+    {
+        sim_time = 0;
+    }
+    virtual ~ModeVisualizer()
+    {
+    }
+    void initPhysics();
+
+    void exitPhysics();
+
+    // disable pick force. non-interactive example.
+    bool pickBody(const btVector3& rayFromWorld, const btVector3& rayToWorld) {
+        return false;
+    } 
+
+    void resetCamera()
+    {
+        float dist = 10;
+        float pitch = 0;
+        float yaw = 90;
+        float targetPos[3] = {0, 3, 0};
+        m_guiHelper->resetCamera(dist, yaw, pitch, targetPos[0], targetPos[1], targetPos[2]);
+    }
+    
+    void stepSimulation(float deltaTime)
+    {
+      btReducedSoftBody* rsb = static_cast<btReducedSoftBody*>(static_cast<btDeformableMultiBodyDynamicsWorld*>(m_dynamicsWorld)->getSoftBodyArray()[0]);
+
+      sim_time += deltaTime;
+      int n_mode = floor(visualize_mode);
+      btScalar scale = sin(rsb->m_eigenvalues[n_mode] * sim_time / frequency_scale);
+      getDeformedShape(rsb, n_mode, scale);
+    }
+    
+    virtual void renderScene()
+    {
+        CommonDeformableBodyBase::renderScene();
+        btDeformableMultiBodyDynamicsWorld* deformableWorld = getDeformableDynamicsWorld();
+        
+        for (int i = 0; i < deformableWorld->getSoftBodyArray().size(); i++)
+        {
+            btSoftBody* rsb = (btSoftBody*)deformableWorld->getSoftBodyArray()[i];
+            {
+                btSoftBodyHelpers::DrawFrame(rsb, deformableWorld->getDebugDrawer());
+                btSoftBodyHelpers::Draw(rsb, deformableWorld->getDebugDrawer(), deformableWorld->getDrawFlags());
+            }
+        }
+    }
+};
+
+void ModeVisualizer::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();
+    btReducedSoftBodySolver* reducedSoftBodySolver = new btReducedSoftBodySolver();
+
+    btDeformableMultiBodyConstraintSolver* sol = new btDeformableMultiBodyConstraintSolver();
+    sol->setDeformableSolver(reducedSoftBodySolver);
+    m_solver = sol;
+
+    m_dynamicsWorld = new btDeformableMultiBodyDynamicsWorld(m_dispatcher, m_broadphase, sol, m_collisionConfiguration, reducedSoftBodySolver);
+    m_guiHelper->createPhysicsDebugDrawer(m_dynamicsWorld);
+
+    // create volumetric soft body
+    {
+      std::string filepath("../../../examples/SoftDemo/");
+      std::string filename = filepath + "mesh.vtk";
+      btReducedSoftBody* rsb = btReducedSoftBodyHelpers::createFromVtkFile(getDeformableDynamicsWorld()->getWorldInfo(), filename.c_str());
+      
+      rsb->setReducedModes(start_mode, num_modes, rsb->m_nodes.size());
+      btReducedSoftBodyHelpers::readReducedDeformableInfoFromFiles(rsb, filepath.c_str());
+
+      getDeformableDynamicsWorld()->addSoftBody(rsb);
+      rsb->getCollisionShape()->setMargin(0.1);
+      btSoftBodyHelpers::generateBoundaryFaces(rsb);
+    }
+    getDeformableDynamicsWorld()->setImplicit(false);
+    m_guiHelper->autogenerateGraphicsObjects(m_dynamicsWorld);
+    
+    {
+      SliderParams slider("Visualize Mode", &visualize_mode);
+      slider.m_minVal = 0;
+      slider.m_maxVal = num_modes;
+      if (m_guiHelper->getParameterInterface())
+          m_guiHelper->getParameterInterface()->registerSliderFloatParameter(slider);
+    }
+    {
+      SliderParams slider("Frequency Reduction", &frequency_scale);
+      slider.m_minVal = 1;
+      slider.m_maxVal = 1e3;
+      if (m_guiHelper->getParameterInterface())
+          m_guiHelper->getParameterInterface()->registerSliderFloatParameter(slider);
+    }
+}
+
+void ModeVisualizer::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* ReducedModeVisualizerCreateFunc(struct CommonExampleOptions& options)
+{
+    return new ModeVisualizer(options.m_guiHelper);
+}
+
+

examples/ReducedDeformableDemo/ModeVisualizer.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 _REDUCED_MODE_VISUALIZER_H
+#define _REDUCED_MODE_VISUALIZER_H
+
+class CommonExampleInterface* ReducedModeVisualizerCreateFunc(struct CommonExampleOptions& options);
+
+#endif  //_REDUCED_MODE_VISUALIZER_H