org.ams.physics.things.AbstractThingWithBody.java Source code

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Here is the source code for org.ams.physics.things.AbstractThingWithBody.java

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/*
 *
 *  The MIT License (MIT)
 *
 *  Copyright (c) <2015> <Andreas Modahl>
 *
 *  Permission is hereby granted, free of charge, to any person obtaining a copy
 *  of this software and associated documentation files (the "Software"), to deal
 *  in the Software without restriction, including without limitation the rights
 *  to use, copy, modify, merge, publish, distribute, sublicense, and/or sell
 *  copies of the Software, and to permit persons to whom the Software is
 *  furnished to do so, subject to the following conditions:
 *
 *  The above copyright notice and this permission notice shall be included in
 *  all copies or substantial portions of the Software.
 *
 *  THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
 *  IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
 *  FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE
 *  AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER
 *  LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM,
 *  OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN
 *  THE SOFTWARE.
 *
 */

/*
 * To change this license header, choose License Headers in Project Properties.
 * To change this template file, choose Tools | Templates
 * and open the template in the editor.
 */
package org.ams.physics.things;

import com.badlogic.gdx.math.Vector2;
import com.badlogic.gdx.physics.box2d.Body;
import com.badlogic.gdx.physics.box2d.BodyDef;
import com.badlogic.gdx.physics.box2d.Fixture;
import com.badlogic.gdx.physics.box2d.FixtureDef;
import org.ams.physics.things.def.ThingDef;
import org.ams.physics.things.def.ThingWithBodyDef;
import org.ams.physics.world.BoxWorld;

/**
 * @author Andreas
 */
public abstract class AbstractThingWithBody extends AbstractThing implements ThingWithBody {

    /**
     * Definition from when this thing was created. Some values can change.
     */
    protected BodyDef bodyDef;
    /**
     * Definition from when this thing was created. Some values can change.
     */
    protected FixtureDef fixtureDef;

    protected Body body;

    private boolean setTransformLater = false;
    private float angleForLater;
    private Vector2 posForLater;

    /**
     * If the value is 0 then this property is ignored. Otherwise all
     * things with equal value will never collide.
     */
    protected int antiCollisionGroup = 0;

    public AbstractThingWithBody(ThingWithBodyDef def) {
        super(def);
        initFromDefinition(def);
    }

    protected void initFromDefinition(ThingWithBodyDef def) {
        bodyDef = new BodyDef();

        bodyDef.active = def.active;
        bodyDef.angle = def.angle;
        bodyDef.angularDamping = def.angularDamping;
        bodyDef.awake = def.awake;
        bodyDef.bullet = def.bullet;
        bodyDef.fixedRotation = def.fixedRotation;
        bodyDef.linearDamping = def.linearDamping;
        bodyDef.position.set(def.position);
        bodyDef.type = def.type;

        fixtureDef = new FixtureDef();

        fixtureDef.density = def.density;
        fixtureDef.friction = def.friction;
        fixtureDef.restitution = def.restitution;
        fixtureDef.filter.categoryBits = def.categoryBits;
        fixtureDef.filter.groupIndex = def.groupIndex;
        fixtureDef.filter.maskBits = def.maskBits;

        antiCollisionGroup = def.antiCollisionGroup;
    }

    @Override
    public void thingHasBeenAddedToBoxWorld(BoxWorld boxWorld) {
        super.thingHasBeenAddedToBoxWorld(boxWorld);

        body = boxWorld.world.createBody(bodyDef);
        body.setUserData(this);

        if (setTransformLater) {
            body.setTransform(posForLater.x, posForLater.y, angleForLater);
        }

        // set some initial values to avoid this polygon being rendered on (0,0) the first frame
        float angle = body.getAngle();
        Vector2 pos = body.getPosition();

        lastPhysicsPos.set(pos);
        lastPhysicsAngle = angle;

    }

    @Override
    public boolean hasBody() {
        return true;
    }

    @Override
    public Body getBody() {
        return body;
    }

    @Override
    public void setAntiCollisionGroup(int i) {
        antiCollisionGroup = i;
    }

    @Override
    public int getAntiCollisionGroup() {
        return antiCollisionGroup;
    }

    @Override
    public void dispose() {
        super.dispose();
        body = null;
    }

    @Override
    public void interpolate(float f) {

        interpolatedPosition.x = lastPhysicsPos.x * f;
        interpolatedPosition.y = lastPhysicsPos.y * f;

        interpolatedPosition.x += body.getPosition().x * (1 - f);
        interpolatedPosition.y += body.getPosition().y * (1 - f);

        interpolatedAngle = lastPhysicsAngle * f;
        interpolatedAngle += body.getAngle() * (1 - f);

    }

    @Override
    public void storeCurrentState() {
        lastPhysicsPos.set(body.getPosition());
        lastPhysicsAngle = body.getAngle();
    }

    @Override
    public void setTransform(float x, float y, float angle) {
        if (body == null) {
            setTransformLater = true;
            posForLater = new Vector2(x, y);
            angleForLater = angle;
        } else {
            body.setTransform(x, y, angle);
        }
    }

    @Override
    public float getInterpolatedAngle() {
        return interpolatedAngle;
    }

    @Override
    public Vector2 getInterpolatedPosition() {
        return interpolatedPosition;
    }

    @Override
    public Vector2 getPosition() {
        if (body != null)
            return body.getPosition();
        return posForLater != null ? posForLater : new Vector2();
    }

    @Override
    public float getAngle() {
        if (body != null)
            return body.getAngle();
        return angleForLater;
    }

    @Override
    public void setFriction(float friction) {
        fixtureDef.friction = friction;
        if (body != null) {
            for (Fixture fixture : body.getFixtureList()) {
                fixture.setFriction(friction);
            }
        }
    }

    @Override
    public float getFriction() {
        return fixtureDef.friction;
    }
}