@Override
public boolean touchDown(int x, int y, int pointer, int newParam) {
// translate the mouse coordinates to world coordinates
testPoint.set(x, y, 0);
camera.unproject(testPoint);
// ask the world which bodies are within the given
// bounding box around the mouse pointer
hitBody = null;
world.QueryAABB(
callback, testPoint.x - 0.1f, testPoint.y - 0.1f, testPoint.x + 0.1f, testPoint.y + 0.1f);
// if we hit something we create a new mouse joint
// and attach it to the hit body.
if (hitBody != null) {
MouseJointDef def = new MouseJointDef();
def.bodyA = groundBody;
def.bodyB = hitBody;
def.collideConnected = true;
def.target.set(testPoint.x, testPoint.y);
def.maxForce = 1000.0f * hitBody.getMass();
mouseJoint = (MouseJoint) world.createJoint(def);
hitBody.setAwake(true);
} else {
for (Body box : boxes) world.destroyBody(box);
boxes.clear();
createBoxes();
}
return false;
}
@Override
public void render() {
Gdx.gl.glClearColor(0, 0, 0, 1);
Gdx.gl.glClear(GL20.GL_COLOR_BUFFER_BIT);
camera.position.set(circleBody.getPosition().x, circleBody.getPosition().y, 0);
camera.update();
renderer.render(world, camera.combined);
System.out.println(
"player.getPosition().x = "
+ player.getPosition().x
+ "\nplayer.getPosition().y = "
+ player.getPosition().y
+ "\ncamera.position = "
+ camera.position);
Sprite sprite;
sprite = (Sprite) circleBody.getUserData();
// set position and width and height and makes sure it is in the center
sprite.setBounds(
convertToWorld(circleBody.getPosition().x) - sprite.getWidth() / 2,
convertToWorld(circleBody.getPosition().y) - sprite.getHeight() / 2,
convertToWorld(circleShape.getRadius() * 2),
convertToWorld(circleShape.getRadius() * 2));
tiledMapRenderer.setView(camera);
tiledMapRenderer.render();
System.out.println(
"Bouncing circle: " + circleBody.getMass() + "\n" + "Player: " + player.getMass());
// world.step(1/45f, 6, 2);
world.step(Gdx.graphics.getDeltaTime(), 4, 4);
player.setAwake(true);
// camera.project(point.set(player.getPosition().x, player.getPosition().y, 0));
// logger.log();
batch.begin();
// Circle.draw(batch);
sprite.draw(batch);
batch.end();
}
public static void moveTo(Entity entity, Vector2 destination) {
Physics physicsComponent = EntityUtil.getComponent(entity, Physics.class);
Body body = physicsComponent.getBody();
float mass = body.getMass();
Vector2 currentVelocity = body.getLinearVelocity();
Vector2 position = body.getPosition();
Vector2 desiredVelocity =
destination.cpy().sub(position).nor().scl(physicsComponent.getMaxSpeed());
Vector2 impulse = desiredVelocity.sub(currentVelocity).scl(mass);
PhysicsUtil.applyImpulse(entity, impulse);
}
@Override
public boolean touchUp(int x, int y, int arg2, int arg3) {
Vector3 coordinates = new Vector3(x, y, 0);
camera.unproject(coordinates);
if (lastTouchPolygon != null) {
Vector2 impulse =
new Vector2(coordinates.x, coordinates.y)
.sub(lastTouchCoordinates)
.scl(lastTouchPolygon.getMass());
Log.log(
"LiveMode.touchUp",
"applying impulse: " + impulse + " on body: " + lastTouchPolygon.getPosition());
lastTouchPolygon.applyLinearImpulse(
impulse, lastTouchPolygonLocalCoordinates.add(lastTouchPolygon.getPosition()), true);
lastTouchCoordinates = null;
lastTouchPolygon = null;
lastTouchPolygonLocalCoordinates = null;
}
return false;
}
/**
* adjust the density so that the mass has the given value
*
* @param mass
*/
public void changeMass(float mass) {
fixture.setDensity(mass / body.getMass() * fixture.getDensity());
body.resetMassData();
}
/**
* @param f - fixture that is affected
* @return true if force was applied, false otherwise.
*/
private boolean ApplyToFixture(Fixture f) {
float shapeDensity = mUseDensity ? f.getDensity() : mFluidDensity;
// don't bother with buoyancy on sensors or fixtures with no density
if (f.isSensor() || (shapeDensity == 0)) {
return false;
}
Body body = f.getBody();
mAreac.set(Vector2.Zero);
mMassc.set(Vector2.Zero);
float area = 0;
// Get shape for displacement area calculations
Shape shape = f.getShape();
mSC.set(Vector2.Zero);
float sarea;
switch (shape.getType()) {
case Circle:
sarea =
B2ShapeExtensions.ComputeSubmergedArea(
(CircleShape) shape, mSurfaceNormal, mSurfaceHeight, body.getTransform(), mSC);
break;
case Chain:
sarea =
B2ShapeExtensions.ComputeSubmergedArea(
(ChainShape) shape, mSurfaceNormal, mSurfaceHeight, body.getTransform(), mSC);
break;
case Edge:
sarea =
B2ShapeExtensions.ComputeSubmergedArea(
(EdgeShape) shape, mSurfaceNormal, mSurfaceHeight, body.getTransform(), mSC);
break;
case Polygon:
sarea =
B2ShapeExtensions.ComputeSubmergedArea(
(PolygonShape) shape, mSurfaceNormal, mSurfaceHeight, body.getTransform(), mSC);
break;
default:
sarea = 0;
break;
}
area += sarea;
mAreac.x += sarea * mSC.x;
mAreac.y += sarea * mSC.y;
float mass = sarea * shapeDensity;
mMassc.x += sarea * mSC.x * shapeDensity;
mMassc.y += sarea * mSC.y * shapeDensity;
mAreac.x /= area;
mAreac.y /= area;
mMassc.x /= mass;
mMassc.y /= mass;
if (area < Float.MIN_VALUE) {
return false;
}
if (DEBUG_BUOYANCY) {
// Run debug w/HCR to see the effects of different fluid densities / linear drag
mFluidDensity = 2f;
mLinearDrag = 5;
mAngularDrag = 2;
}
// buoyancy force.
mTmp.set(mGravity).scl(-mFluidDensity * area);
body.applyForce(mTmp, mMassc, true); // multiply by -density to invert gravity
// linear drag.
mTmp.set(
body.getLinearVelocityFromWorldPoint(mAreac).sub(mFluidVelocity).mul(-mLinearDrag * area));
body.applyForce(mTmp, mAreac, true);
// angular drag.
float bodyMass = body.getMass();
if (bodyMass < 1) // prevent a huge torque from being generated...
{
bodyMass = 1;
}
float torque = -body.getInertia() / bodyMass * area * body.getAngularVelocity() * mAngularDrag;
body.applyTorque(torque, true);
return true;
}
// Get the combined mass of all bodies
public float getMass() {
float mass = 0;
for (Body b : scene.getBodies()) mass += b.getMass();
return mass;
}
