TestSoftBody.java

/*
 Copyright (c) 2019, Stephen Gold
 All rights reserved.

 Redistribution and use in source and binary forms, with or without
 modification, are permitted provided that the following conditions are met:
 * Redistributions of source code must retain the above copyright
 notice, this list of conditions and the following disclaimer.
 * Redistributions in binary form must reproduce the above copyright
 notice, this list of conditions and the following disclaimer in the
 documentation and/or other materials provided with the distribution.
 * Neither the name of the copyright holder nor the names of its contributors
 may be used to endorse or promote products derived from this software without
 specific prior written permission.

 THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS "AS IS" AND
 ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED
 WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE
 DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT HOLDER OR CONTRIBUTORS BE LIABLE
 FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
 DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR
 SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER
 CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY,
 OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE
 OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
 */
package jme3utilities.minie.test;

import com.jme3.bullet.PhysicsSoftSpace;
import com.jme3.bullet.SoftPhysicsAppState;
import com.jme3.bullet.collision.shapes.BoxCollisionShape;
import com.jme3.bullet.control.RigidBodyControl;
import com.jme3.bullet.objects.PhysicsRigidBody;
import com.jme3.bullet.objects.PhysicsSoftBody;
import com.jme3.bullet.objects.infos.Sbcp;
import com.jme3.bullet.util.NativeSoftBodyUtil;
import com.jme3.input.KeyInput;
import com.jme3.material.Material;
import com.jme3.math.Vector3f;
import com.jme3.scene.Geometry;
import com.jme3.scene.Mesh;
import com.jme3.scene.shape.Box;
import com.jme3.system.AppSettings;
import java.util.logging.Level;
import java.util.logging.Logger;
import jme3utilities.Misc;
import jme3utilities.MyAsset;
import jme3utilities.minie.DumpFlags;
import jme3utilities.minie.PhysicsDumper;
import jme3utilities.minie.test.mesh.Icosphere;
import jme3utilities.ui.ActionApplication;
import jme3utilities.ui.CameraOrbitAppState;
import jme3utilities.ui.InputMode;

/**
 * Test soft-body physics.
 *
 * @author Stephen Gold sgold@sonic.net
 */
public class TestSoftBody extends ActionApplication {
    // *************************************************************************
    // constants and loggers

    /**
     * magnitude of the gravitational acceleration (≥0)
     */
    final private float gravity = 1f;
    /**
     * mass of the soft body (>0)
     */
    final private float mass = 1f;
    /**
     * pose-matching coefficient: how strongly the soft body will match its
     * default pose (≥0, ≤1)
     */
    final private float poseMatchingCoeff = 0.02f;
    /**
     * radius of the soft body (in world units, >0)
     */
    final private float radius = 0.5f;
    /**
     * message logger for this class
     */
    final public static Logger logger
            = Logger.getLogger(TestSoftBody.class.getName());
    /**
     * application name (for the title bar of the app's window)
     */
    final private static String applicationName
            = TestSoftBody.class.getSimpleName();
    // *************************************************************************
    // fields

    /**
     * space for physics simulation
     */
    private PhysicsSoftSpace physicsSpace;
    // *************************************************************************
    // new methods exposed

    /**
     * Main entry point for the TestSoftBody application.
     *
     * @param ignored array of command-line arguments (not null)
     */
    public static void main(String[] ignored) {
        /*
         * Mute the chatty loggers in certain packages.
         */
        Misc.setLoggingLevels(Level.WARNING);

        TestSoftBody application = new TestSoftBody();
        /*
         * Customize the window's title bar.
         */
        AppSettings settings = new AppSettings(true);
        settings.setTitle(applicationName);

        settings.setGammaCorrection(true);
        settings.setSamples(4); // anti-aliasing
        settings.setVSync(true);
        application.setSettings(settings);

        application.start();
    }
    // *************************************************************************
    // ActionApplication methods

    /**
     * Initialize this application.
     */
    @Override
    public void actionInitializeApplication() {
        configureCamera();
        configurePhysics();
        addBox();
        addFatBall();
    }

    /**
     * Add application-specific hotkey bindings and override existing ones.
     */
    @Override
    public void moreDefaultBindings() {
        InputMode dim = getDefaultInputMode();

        dim.bind("dump physicsSpace", KeyInput.KEY_O);
        dim.bind("dump scenes", KeyInput.KEY_P);
        dim.bind("signal orbitLeft", KeyInput.KEY_LEFT);
        dim.bind("signal orbitRight", KeyInput.KEY_RIGHT);
        dim.bind("toggle pause", KeyInput.KEY_PERIOD);
    }

    /**
     * Process an action that wasn't handled by the active input mode.
     *
     * @param actionString textual description of the action (not null)
     * @param ongoing true if the action is ongoing, otherwise false
     * @param tpf time interval between frames (in seconds, ≥0)
     */
    @Override
    public void onAction(String actionString, boolean ongoing, float tpf) {
        if (ongoing) {
            switch (actionString) {
                case "dump physicsSpace":
                    dumpPhysicsSpace();
                    return;

                case "dump scenes":
                    dumpScenes();
                    return;

                case "toggle pause":
                    togglePause();
                    return;
            }
        }
        super.onAction(actionString, ongoing, tpf);
    }
    // *************************************************************************
    // private methods

    /**
     * Add a large static box to the scene, to serve as a platform.
     */
    private void addBox() {
        float halfExtent = 50f; // mesh units
        Mesh mesh = new Box(halfExtent, halfExtent, halfExtent);
        Geometry boxGeometry = new Geometry("box", mesh);
        rootNode.attachChild(boxGeometry);

        boxGeometry.move(0f, -halfExtent, 0f);
        Material material = MyAsset.createDebugMaterial(assetManager);
        boxGeometry.setMaterial(material);

        BoxCollisionShape shape = new BoxCollisionShape(halfExtent);
        float boxMass = PhysicsRigidBody.massForStatic;
        RigidBodyControl boxBody = new RigidBodyControl(shape, boxMass);
        boxGeometry.addControl(boxBody);
        boxBody.setApplyScale(true);
        boxBody.setPhysicsSpace(physicsSpace);
    }

    /**
     * Add a squishy ball to the scene.
     */
    private void addFatBall() {
        int numSteps = 3;
        Mesh mesh = new Icosphere(numSteps, radius);
        PhysicsSoftBody softBody = new PhysicsSoftBody();
        NativeSoftBodyUtil.appendFromTriMesh(mesh, softBody);
        softBody.setMass(mass);

        PhysicsSoftBody.Config config = softBody.getSoftConfig();
        config.set(Sbcp.PoseMatching, poseMatchingCoeff);

        boolean setVolumePose = false;
        boolean setFramePose = true;
        softBody.setPose(setVolumePose, setFramePose);

        softBody.setPhysicsLocation(new Vector3f(0f, 3f, 0f));
        physicsSpace.add(softBody);
        softBody.setGravity(new Vector3f(0f, -gravity, 0f));
    }

    /**
     * Configure the camera during startup.
     */
    private void configureCamera() {
        flyCam.setDragToRotate(true);
        flyCam.setMoveSpeed(4f);
        cam.setLocation(new Vector3f(0f, 1.2f, 5f));

        CameraOrbitAppState orbitState
                = new CameraOrbitAppState(cam, "orbitLeft", "orbitRight");
        stateManager.attach(orbitState);
    }

    /**
     * Configure physics during startup.
     */
    private void configurePhysics() {
        SoftPhysicsAppState bulletAppState = new SoftPhysicsAppState();
        bulletAppState.setDebugEnabled(true);
        stateManager.attach(bulletAppState);
        physicsSpace = bulletAppState.getPhysicsSoftSpace();
    }

    /**
     * Process a "dump physicsSpace" action.
     */
    private void dumpPhysicsSpace() {
        PhysicsDumper dumper = new PhysicsDumper();
        dumper.setEnabled(DumpFlags.JointsInBodies, true);
        dumper.setEnabled(DumpFlags.JointsInSpaces, true);
        dumper.dump(physicsSpace);
    }

    /**
     * Process a "dump scenes" action.
     */
    private void dumpScenes() {
        PhysicsDumper dumper = new PhysicsDumper();
        dumper.setEnabled(DumpFlags.Transforms, true);
        dumper.dump(renderManager);
    }

    /**
     * Toggle the animation and physics simulation: paused/running.
     */
    private void togglePause() {
        float newSpeed = (speed > 1e-12f) ? 1e-12f : 1f;
        setSpeed(newSpeed);
    }
}