import com.badlogic.gdx.physics.box2d.MassData; //导入依赖的package包/类
public static Body createCircle() {
	if (!BodyFactory.initialized) {
		throw new IllegalStateException("You must initialize BodyFactory before using its functions");
	}
	final BodyDef testBodyDef2 = new BodyDef();
	testBodyDef2.position.set(2, 3);
	testBodyDef2.type = BodyDef.BodyType.DynamicBody;
	testBodyDef2.fixedRotation = true;
	final Body body2 = BodyFactory.world.createBody(testBodyDef2);
	final CircleShape testShape2 = new CircleShape();
	testShape2.setRadius(1f);
	final FixtureDef testFixtureDef2 = new FixtureDef();
	testFixtureDef2.shape = testShape2;
	testFixtureDef2.density = 25f;
	testFixtureDef2.friction = 1f;
	testFixtureDef2.restitution = 0;
	body2.createFixture(testFixtureDef2);
	final MassData md = body2.getMassData();
	md.mass = 80; // kg
	body2.setMassData(md);
	// System.out.println("circle - mass: " + body2.getMassData().mass + " density: " + body2.getFixtureList().get(0).getDensity());
	testShape2.dispose();
	return body2;
}
 

import com.badlogic.gdx.physics.box2d.MassData; //导入依赖的package包/类
public void create () {
	cam = new OrthographicCamera(48, 32);
	cam.position.set(0, 15, 0);
	renderer = new Box2DDebugRenderer();

	world = new World(new Vector2(0, -10), true);
	Body body = world.createBody(new BodyDef());
	CircleShape shape = new CircleShape();
	shape.setRadius(1f);
	MassData mass = new MassData();
	mass.mass = 1f;
	body.setMassData(mass);
	body.setFixedRotation(true);
	body.setType(BodyType.KinematicBody);
	body.createFixture(shape, 1);
	body.setBullet(true);
	body.setTransform(new Vector2(0, 0), body.getAngle());
	body.setLinearVelocity(new Vector2(50f, 0));
}
 

import com.badlogic.gdx.physics.box2d.MassData; //导入依赖的package包/类
/**
 * @param position
 * @return Body
 */
public static Body createPlayerPlatformerBody2(final Vector2 position) {
	if (!BodyFactory.initialized) {
		throw new IllegalStateException("You must initialize BodyFactory before using its functions");
	}
	final BodyDef bodyDef = new BodyDef();
	bodyDef.position.set(position.x, position.y);
	bodyDef.type = BodyDef.BodyType.DynamicBody;
	bodyDef.fixedRotation = true;
	// create body with world
	final Body b2Body = BodyFactory.world.createBody(bodyDef);

	// create shape
	final PolygonShape boxShape = new PolygonShape();
	boxShape.setAsBox(0.4f / 2f, 1.6f / 2f); // width: 50cm, heigth: 1,8meters ... div 2, because setAsBox(...) calcs in half sizes

	// create fixture to attach shape to body
	final FixtureDef fixtureDef = new FixtureDef();
	fixtureDef.shape = boxShape;
	fixtureDef.density = 20f; // BMI of human?
	fixtureDef.friction = 0.5f;
	fixtureDef.restitution = 0.1f;
	b2Body.createFixture(fixtureDef);

	final MassData md = b2Body.getMassData();
	md.mass = 60; // kg
	b2Body.setMassData(md);
	boxShape.dispose(); // clean up!!
	return b2Body;
}
 

import com.badlogic.gdx.physics.box2d.MassData; //导入依赖的package包/类
/**
 * Genera un cuerpo con forma circular
 * @param world El mundo
 * @param x posici�n X
 * @param y posicion Y
 * @return El cuerpo creado
 */
public static Body createCircleBody(World world, float x, float y) {
	
	// Masa (en kg)
	MassData mass = new MassData();
	mass.mass = 100f;
	
	// Define un cuerpo f�sico din�mico con posici�n en el mundo 2D
	BodyDef bodyDef = new BodyDef();
	bodyDef.type = BodyType.DynamicBody;
	bodyDef.position.set(x, y);
	Body body = world.createBody(bodyDef);
	
	// Define una forma circular de 6 unidades de di�metro
	CircleShape circle = new CircleShape();
	circle.setRadius(6f);
	
	// Define un elemento f�sico y sus propiedades y le asigna la forma circular
	FixtureDef fixtureDef = new FixtureDef();
	// Forma del elemento f�sico
	fixtureDef.shape = circle;
	// Densidad (kg/m^2)
	fixtureDef.density = DENSITY;
	// Coeficiente de fricci�n (0 - 1)
	fixtureDef.friction = FRICTION;
	// Elasticidad (0 - 1)
	fixtureDef.restitution = RESTITUTION;
	// A�ade el elemento f�sico al cuerpo del mundo 2D
	Fixture fixture = body.createFixture(fixtureDef);
	
	// Definir la masa del cuerpo modifica las propiedades (FixtureDef) y viceversa (densidad)
	body.setMassData(mass);
	
	circle.dispose();
	
	return body;
}
 

import com.badlogic.gdx.physics.box2d.MassData; //导入依赖的package包/类
/**
 * Genera un cuerpo con forma de caja
 * @param world El mundo
 * @param x Posici�n x
 * @param y Posici�n y
 * @return El cuerpo creado
 */
public static Body createBoxBody(World world, float x, float y) {

	// Masa (en kg)
	MassData mass = new MassData();
	mass.mass = 100f;
	
	// Define un cuerpo f�sico din�mico con posici�n en el mundo 2D
	BodyDef bodyDef = new BodyDef();
	bodyDef.type = BodyType.DynamicBody;
	bodyDef.position.set(x, y);
	Body body = world.createBody(bodyDef);
	
	// Define una forma circular de 6 unidades de di�metro
	PolygonShape box = new PolygonShape();
	box.setAsBox(10f, 10f);
	
	// Define un elemento f�sico y sus propiedades y le asigna la forma circular
	FixtureDef fixtureDef = new FixtureDef();
	// Forma del elemento f�sico
	fixtureDef.shape = box;
	// Densidad (kg/m^2)
	fixtureDef.density = 10f;
	// Coeficiente de fricci�n (0 - 1)
	fixtureDef.friction = 0.4f;
	// Elasticidad (0 - 1)
	fixtureDef.restitution = 0.1f;
	// A�ade el elemento f�sico al cuerpo del mundo 2D
	Fixture fixture = body.createFixture(fixtureDef);
	
	// Definir la masa del cuerpo modifica las propiedades (FixtureDef) y viceversa (densidad)
	body.setMassData(mass);
	
	box.dispose();
	
	return body;
}
 

import com.badlogic.gdx.physics.box2d.MassData; //导入依赖的package包/类
public Player(World world, float x, float y, float width) {
    super(Assets.getTexture("cage"), new CircleShape(), world, x, y, width);
    this.body.setLinearDamping(2);
    MassData massData = body.getMassData();
    massData.mass = 1;
    this.body.setMassData(massData);
    addController();
}
 

import com.badlogic.gdx.physics.box2d.MassData; //导入依赖的package包/类
private void setMass() {
	MassData masa = new MassData();
	masa.center.set(getWidth()/2, getHeight()/2);
	masa.mass = 25; // Pesa 5 kilogr�mos.
	
	getBody().setMassData(masa);
	getBody().resetMassData();
}
 

import com.badlogic.gdx.physics.box2d.MassData; //导入依赖的package包/类
public MassData getMassData() {
	return massData;
}
 

import com.badlogic.gdx.physics.box2d.MassData; //导入依赖的package包/类
public void setMassData(MassData massData) {
    body.setMassData(massData);
}
 

import com.badlogic.gdx.physics.box2d.MassData; //导入依赖的package包/类
public MeshData(BodyDef bodyDef, MassData massData, FixtureDef[] fixtureDefs) {
    this.bodyDef = bodyDef;
    this.massData = massData;
    this.fixtureDefs = fixtureDefs;
}
 

import com.badlogic.gdx.physics.box2d.MassData; //导入依赖的package包/类
@SuppressWarnings({ "rawtypes", "unchecked" })
@Override
public Body read(Json json, JsonValue jsonData, Class type) 
{
	if(world == null)
		return null;
	BodyDef defaults = RubeDefaults.Body.definition;

	int bodyType = json.readValue("type", int.class, defaults.type.getValue(), jsonData);
	
	if(bodyType == BodyType.DynamicBody.getValue())
		def.type = BodyType.DynamicBody;
	else if(bodyType == BodyType.KinematicBody.getValue())
		def.type = BodyType.KinematicBody;
	else
		def.type = BodyType.StaticBody;
	
	def.position.set(		json.readValue("position", 			Vector2.class, defaults.position, 		jsonData));
	def.linearVelocity.set(	json.readValue("linearVelocity", 	Vector2.class, defaults.linearVelocity, jsonData));
	
	def.angle 			= json.readValue("angle", 			float.class, defaults.angle, 			jsonData);
	def.angularVelocity = json.readValue("angularVelocity", float.class, defaults.angularVelocity, 	jsonData);
	def.linearDamping 	= json.readValue("linearDamping", 	float.class, defaults.linearDamping, 	jsonData);
	def.angularDamping 	= json.readValue("angularDamping", 	float.class, defaults.angularDamping, 	jsonData);
	def.gravityScale 	= json.readValue("gravityScale", 	float.class, defaults.gravityScale, 	jsonData);
	
	def.allowSleep 		= json.readValue("allowSleep", 		boolean.class, defaults.allowSleep, 	jsonData);
	def.awake 			= json.readValue("awake",			boolean.class, defaults.awake, 			jsonData);
	def.fixedRotation 	= json.readValue("fixedRotation", 	boolean.class, defaults.fixedRotation, 	jsonData);
	def.bullet 			= json.readValue("bullet", 			boolean.class, defaults.bullet, 		jsonData);
	def.active 			= json.readValue("active", 			boolean.class, defaults.active, 		jsonData);
	
	Body body = world.createBody(def);
	
	if(def.type == BodyType.DynamicBody)
	{
		Vector2 center = json.readValue("massData-center",  Vector2.class, jsonData);
		float mass = json.readValue("massData-mass", 	float.class, 0.0f, 	jsonData);
		float I = json.readValue("massData-I", 	float.class, 0.0f, 	jsonData);
		
		if(center != null)
		{
			MassData massData = new MassData();
			
			massData.center.set(center);
			massData.mass = mass;
			massData.I = I;
			
			if(massData.mass != 0.0f || massData.I != 0.0f || massData.center.x != 0.0f || massData.center.y != 0.0f)
				body.setMassData(massData);
		}
	}
	scene.parseCustomProperties(json, body, jsonData);
	
	String name = json.readValue("name", String.class, jsonData);
	if (name != null)
	{
	   scene.putNamed(name, body);
	}
	
	fixtureSerializer.setBody(body);
	
	scene.addFixtures(json.readValue("fixture", Array.class, Fixture.class, jsonData));
	
	return body;
}