Java Code Examples for org.jbox2d.collision.shapes.PolygonShape#setAsBox()

private void updateTopAndBottomBounds() {
    BodyDef bodyDef = new BodyDef();
    bodyDef.type = BodyType.STATIC;

    PolygonShape shape = new PolygonShape();
    float hx = mappingView2Body(width);
    float hy = mappingView2Body(proportion);
    shape.setAsBox(hx, hy);

    FixtureDef def = new FixtureDef();
    def.shape = shape;
    def.density = density;
    def.friction = frictionRatio;
    def.restitution = restitutionRatio;

    bodyDef.position.set(0, -hy);
    Body topBody = world.createBody(bodyDef);
    topBody.createFixture(def);

    bodyDef.position.set(0, mappingView2Body(height) + hy);
    Body bottomBody = world.createBody(bodyDef);
    bottomBody.createFixture(def);
}
 

public void makeDomino(float x, float y, boolean horizontal, World world) {

    PolygonShape sd = new PolygonShape();
    sd.setAsBox(.5f * dwidth, .5f * dheight);
    FixtureDef fd = new FixtureDef();
    fd.shape = sd;
    fd.density = ddensity;
    BodyDef bd = new BodyDef();
    bd.type = BodyType.DYNAMIC;
    fd.friction = dfriction;
    fd.restitution = 0.65f;
    bd.position = new Vec2(x, y);
    bd.angle = horizontal ? (float) (Math.PI / 2.0) : 0f;
    Body myBody = getWorld().createBody(bd);
    myBody.createFixture(fd);
  }
 

@Override
public synchronized void step(TestbedSettings settings) {
  super.step(settings);

  if (m_count < MAX_NUM) {
    BodyDef bd = new BodyDef();
    bd.type = BodyType.DYNAMIC;
    bd.position.set(0.0f, 10.0f);
    Body body = m_world.createBody(bd);

    PolygonShape shape = new PolygonShape();
    shape.setAsBox(0.125f, 0.125f);
    body.createFixture(shape, 1.0f);

    ++m_count;
  }
}
 

private void updateLeftAndRightBounds() {
    BodyDef bodyDef = new BodyDef();
    //生成静态刚体
    bodyDef.type = BodyType.STATIC;

    //设置形状 - 多边形
    PolygonShape shape = new PolygonShape();

    //hx 1  hy 屏幕高度
    float hx = mappingView2Body(proportion);
    float hy = mappingView2Body(height);
    shape.setAsBox(hx, hy);

    //设置 系数
    FixtureDef def = new FixtureDef();
    def.shape = shape;
    def.density = density;
    def.friction = frictionRatio;
    def.restitution = restitutionRatio;

    //-1 高度
    bodyDef.position.set(-hx, hy);
    Body leftBody = world.createBody(bodyDef);
    //设置位置
    leftBody.createFixture(def);

    //这里便于理解 应该是 w + 1  h
    //而不是 w + 1 0 验证结果一样
    bodyDef.position.set(mappingView2Body(width) + hx, 0);
    Body rightBody = world.createBody(bodyDef);
    rightBody.createFixture(def);
}
 

private Box2d() {
  // Define the gravity vector.
  Vec2 gravity = new Vec2(0f, -9.8f);

  // Initialise the World.
  world = new World(gravity);

  // Create the ground (Something for dynamic bodies to collide with).
  {
    BodyDef groundBodyDef = new BodyDef();
    groundBodyDef.position.set(10, -40);
    groundBodyDef.type = BodyType.STATIC;

    // Create the Body in the World.
    Body ground = world.createBody(groundBodyDef);

    // Create the fixtures (physical aspects) of the ground body.
    FixtureDef groundEdgeFixtureDef = new FixtureDef();
    groundEdgeFixtureDef.density = 1.0f;
    groundEdgeFixtureDef.friction = 1.0f;
    groundEdgeFixtureDef.restitution = 0.4f;

    PolygonShape groundEdge = new PolygonShape();
    groundEdgeFixtureDef.shape = groundEdge;

    // Bottom Edge.
    groundEdge.setAsBox(100, 1);
    ground.createFixture(groundEdgeFixtureDef);
  }

  for (int i = 0; i < NUM_BALLS; i++) {
    spawnBall();
  }
}
 

@Override
public void initTest(boolean deserialized) {
  {
    BodyDef bd = new BodyDef();
    bd.type = BodyType.DYNAMIC;
    bd.allowSleep = false;
    bd.position.set(0.0f, 10.0f);
    Body body = m_world.createBody(bd);

    PolygonShape shape = new PolygonShape();
    shape.setAsBox(0.5f, 10.0f, new Vec2(10.0f, 0.0f), 0.0f);
    body.createFixture(shape, 5.0f);
    shape.setAsBox(0.5f, 10.0f, new Vec2(-10.0f, 0.0f), 0.0f);
    body.createFixture(shape, 5.0f);
    shape.setAsBox(10.0f, 0.5f, new Vec2(0.0f, 10.0f), 0.0f);
    body.createFixture(shape, 5.0f);
    shape.setAsBox(10.0f, 0.5f, new Vec2(0.0f, -10.0f), 0.0f);
    body.createFixture(shape, 5.0f);

    RevoluteJointDef jd = new RevoluteJointDef();
    jd.bodyA = getGroundBody();
    jd.bodyB = body;
    jd.localAnchorA.set(0.0f, 10.0f);
    jd.localAnchorB.set(0.0f, 0.0f);
    jd.referenceAngle = 0.0f;
    jd.motorSpeed = 0.05f * MathUtils.PI;
    jd.maxMotorTorque = 1e8f;
    jd.enableMotor = true;
    m_joint = (RevoluteJoint) m_world.createJoint(jd);
  }
  m_count = 0;
}
 

@Override
public void initTest(boolean argDeserialized) {
	
	input.transformA = new Transform();
	input.transformB = new Transform();
	{
		m_transformA = new Transform();
		m_transformA.setIdentity();
		m_transformA.p.set(0.0f, -0.2f);
		m_polygonA = new PolygonShape();
		m_polygonA.setAsBox(10.0f, 0.2f);
	}
	
	{
		m_positionB = new Vec2();
		m_positionB.set(12.017401f, 0.13678508f);
		m_angleB = -0.0109265f;
		
		m_transformB = new Transform();
		m_transformB.set(m_positionB, m_angleB);
		
		m_polygonB = new PolygonShape();
		m_polygonB.setAsBox(2.0f, 0.1f);
	}
	for (int i = 0; i < v.length; i++) {
		v[i] = new Vec2();
	}
}
 

private Shape createPolygonBody(View childView) {
    PolygonShape polygonShape = new PolygonShape();
    //形状的大小为 view 的一半 （还可以等比缩放）
    polygonShape.setAsBox(mappingView2Body(childView.getWidth() / 2), mappingView2Body(childView.getHeight() / 2));
    return polygonShape;
}
 

@Override
public void initTest(boolean deserialized) {
  if (deserialized) {
    return;
  }
  // Ground body
  {
    EdgeShape shape = new EdgeShape();
    shape.set(new Vec2(-50.0f, 0.0f), new Vec2(50.0f, 0.0f));

    FixtureDef sd = new FixtureDef();
    sd.shape = shape;

    BodyDef bd = new BodyDef();
    Body ground = getWorld().createBody(bd);
    ground.createFixture(sd);
  }

  float xLo = -5.0f, xHi = 5.0f;
  float yLo = 2.0f, yHi = 35.0f;

  // Small triangle
  Vec2 vertices[] = new Vec2[3];
  vertices[0] = new Vec2(-1.0f, 0.0f);
  vertices[1] = new Vec2(1.0f, 0.0f);
  vertices[2] = new Vec2(0.0f, 2.0f);

  PolygonShape polygon = new PolygonShape();
  polygon.set(vertices, 3);

  FixtureDef triangleShapeDef = new FixtureDef();
  triangleShapeDef.shape = polygon;
  triangleShapeDef.density = 1.0f;

  BodyDef triangleBodyDef = new BodyDef();
  triangleBodyDef.type = BodyType.DYNAMIC;
  triangleBodyDef.position.set(MathUtils.randomFloat(xLo, xHi), MathUtils.randomFloat(yLo, yHi));

  Body body1 = getWorld().createBody(triangleBodyDef);
  body1.createFixture(triangleShapeDef);

  // Large triangle (recycle definitions)
  vertices[0].mulLocal(2.0f);
  vertices[1].mulLocal(2.0f);
  vertices[2].mulLocal(2.0f);
  polygon.set(vertices, 3);

  triangleBodyDef.position.set(MathUtils.randomFloat(xLo, xHi), MathUtils.randomFloat(yLo, yHi));

  Body body2 = getWorld().createBody(triangleBodyDef);
  body2.createFixture(triangleShapeDef);

  // Small box
  polygon.setAsBox(1.0f, 0.5f);

  FixtureDef boxShapeDef = new FixtureDef();
  boxShapeDef.shape = polygon;
  boxShapeDef.density = 1.0f;

  BodyDef boxBodyDef = new BodyDef();
  boxBodyDef.type = BodyType.DYNAMIC;
  boxBodyDef.position.set(MathUtils.randomFloat(xLo, xHi), MathUtils.randomFloat(yLo, yHi));

  Body body3 = getWorld().createBody(boxBodyDef);
  body3.createFixture(boxShapeDef);

  // Large box (recycle definitions)
  polygon.setAsBox(2.0f, 1.0f);
  boxBodyDef.position.set(MathUtils.randomFloat(xLo, xHi), MathUtils.randomFloat(yLo, yHi));

  Body body4 = getWorld().createBody(boxBodyDef);
  body4.createFixture(boxShapeDef);

  // Small circle
  CircleShape circle = new CircleShape();
  circle.m_radius = 1.0f;

  FixtureDef circleShapeDef = new FixtureDef();
  circleShapeDef.shape = circle;
  circleShapeDef.density = 1.0f;

  BodyDef circleBodyDef = new BodyDef();
  circleBodyDef.type = BodyType.DYNAMIC;
  circleBodyDef.position.set(MathUtils.randomFloat(xLo, xHi), MathUtils.randomFloat(yLo, yHi));

  Body body5 = getWorld().createBody(circleBodyDef);
  body5.createFixture(circleShapeDef);

  // Large circle
  circle.m_radius *= 2.0f;
  circleBodyDef.position.set(MathUtils.randomFloat(xLo, xHi), MathUtils.randomFloat(yLo, yHi));

  Body body6 = getWorld().createBody(circleBodyDef);
  body6.createFixture(circleShapeDef);
}