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RbdBallDrop

Rigid ball drop example


Description

This example demonstrates various rigid bodies using iMSTK's position-based-dynamics solver.

RbdBallDropExample.cpp

/*
** This file is part of the Interactive Medical Simulation Toolkit (iMSTK)
** iMSTK is distributed under the Apache License, Version 2.0.
** See accompanying NOTICE for details.
*/

#include "imstkCamera.h"
#include "imstkCollisionUtils.h"
#include "imstkDirectionalLight.h"
#include "imstkGeometryUtilities.h"
#include "imstkKeyboardDeviceClient.h"
#include "imstkKeyboardSceneControl.h"
#include "imstkMouseDeviceClient.h"
#include "imstkMouseSceneControl.h"
#include "imstkNew.h"
#include "imstkPlane.h"
#include "imstkRbdConstraint.h"
#include "imstkRenderMaterial.h"
#include "imstkRigidBodyModel2.h"
#include "imstkRigidObject2.h"
#include "imstkRigidObjectCollision.h"
#include "imstkScene.h"
#include "imstkSceneManager.h"
#include "imstkSimulationManager.h"
#include "imstkSimulationUtils.h"
#include "imstkSphere.h"
#include "imstkSurfaceMesh.h"
#include "imstkUnidirectionalPlaneToSphereCD.h"
#include "imstkVisualModel.h"
#include "imstkVTKViewer.h"

using namespace imstk;

namespace
{
} // namespace

///
/// \brief This examples demonstrates rigid body interaction between
/// primitives
///
int
main()
{
    // Write log to stdout and file
    Logger::startLogger();

    auto scene = std::make_shared<Scene>("RbdMeshMeshCollision");

    // This model is shared among interacting rigid bodies
    // In most cases instances of iMSTK object should be created
    // on the heap and stored in std::shared_ptr
    auto rbdModel = std::make_shared<RigidBodyModel2>();

    // iMSTK coordinates are right handed with Y pointing up
    // While we have defined types for Vectors and Matrices
    // these are all Eigen https://eigen.tuxfamily.org/index.php
    // types and all of Eigen is available in iMSTK
    rbdModel->getConfig()->m_gravity = Vec3d(0.0, -9.8, 0.0);
    rbdModel->getConfig()->m_maxNumIterations = 10;

    // iMSTK knows about various kinds of geometry, amongst others
    // analytical shapes and meshes, here a analytical sphere is used
    auto sphere = std::make_shared<Sphere>(Vec3d(0, 0, 0), 0.5);

    // Create a SceneObject that is a RigidObject
    // Then we set up the object with all the data necessary
    auto sphereObject = std::make_shared<RigidObject2>("Sphere");

    // Give the object something to visualize, this can be shortcut by using
    // addVisualGeometry()
    auto sphereVisualModel = std::make_shared<VisualModel>();
    sphereVisualModel->setGeometry(sphere);
    sphereObject->addVisualModel(sphereVisualModel);

    // Customize the look using a material
    auto sphereMaterial = std::make_shared<RenderMaterial>();
    sphereMaterial->setDiffuseColor(Color(1.0, 0.333, 0.259));
    sphereMaterial->setShadingModel(RenderMaterial::ShadingModel::PBR);
    sphereMaterial->setRoughness(0.5);
    sphereMaterial->setMetalness(0.5);
    sphereVisualModel->setRenderMaterial(sphereMaterial);

    // This is the geometry used for collision detection
    sphereObject->setCollidingGeometry(sphere);

    // Forces and physical effects are applied to the physics geometry
    sphereObject->setPhysicsGeometry(sphere);

    sphereObject->setDynamicalModel(rbdModel);
    sphereObject->getRigidBody()->m_mass = 1.0;

    sphereObject->getRigidBody()->m_initPos = Vec3d(0.0, 3.0, 0.0);
    sphereObject->getRigidBody()->m_intertiaTensor = Mat3d::Identity();

    // Finally add the object to the scene
    scene->addSceneObject(sphereObject);

    // Create a plane at the origin with a normal along the Y-Axis
    auto plane = std::make_shared<Plane>(Vec3d::Zero(), Vec3d::UnitY());

    // This "width" is just used visually, this is an analytical plane
    // that is infinite
    plane->setWidth(10.0);

    // A CollidingObject is static and will not react to forces
    auto planeObject = std::make_shared<CollidingObject>("Plane");
    planeObject->setVisualGeometry(plane);
    planeObject->setCollidingGeometry(plane);
    scene->addSceneObject(planeObject);

    // To affect collision detection and response the appropriate interaction has to be instantiated
    // and added to the scene, the type of the interaction is dependent on the interacting model types
    // in this case Rigid and Colliding (Static) object
    // the type of the collision detection is dependent on the kinds of geometry involved
    // Add collisions for all the rigid bodies with the bowl
    scene->addInteraction(
        std::make_shared<RigidObjectCollision>(sphereObject, planeObject, UnidirectionalPlaneToSphereCD::getStaticTypeName()));

    // Camera
    scene->getActiveCamera()->setPosition(0, 3, 20);
    scene->getActiveCamera()->setFocalPoint(0.0, 0.0, 0.0);
    scene->getActiveCamera()->setViewUp(0, 1, 0);

    // Light
    imstkNew<DirectionalLight> light;
    light->setIntensity(1.0);
    scene->addLight("light", light);

    // Setup a viewer to render in its own thread
    auto viewer = std::make_shared<VTKViewer>();
    viewer->setActiveScene(scene);

    // Setup a scene manager to advance the scene in its own thread
    auto sceneManager = std::make_shared<SceneManager>();
    sceneManager->setActiveScene(scene);
    sceneManager->pause();

    // The simulation manager is responsible to direct multiple modules
    auto simulationManager = std::make_shared<SimulationManager>();
    simulationManager->addModule(viewer);
    simulationManager->addModule(sceneManager);
    simulationManager->setDesiredDt(0.001);

    // Add default mouse and keyboard controls to the viewer
    std::shared_ptr<Entity> mouseAndKeyControls =
        SimulationUtils::createDefaultSceneControl(simulationManager);
    scene->addSceneObject(mouseAndKeyControls);

    // iMSTK utilizes an event system this is one of many ways to connect to this system
    // postUpdateFunction will be called every time the SceneManager posts a
    // postUdate event, in this case a lambda is used to capture the scene by
    // value as we don't have an object scope to use use, depending on your needs a free function
    // or a member function can be used as callbacks for events.
    connect<Event>(sceneManager, &SceneManager::postUpdate, [scene](Event*) {
            // Remove comment to print out the elapsed time every frame
            // LOG(INFO) << "Elapsed: " << scene->getSceneTime();
        });

    // By default the scene will start "paused" press space to start the simulation
    // look at the console for more instructions about available key strokes
    simulationManager->start();

    return 0;
}