com.badlogic.gdx.physics.box2d.Contact Java Examples

@Override
public void endContact(Contact contact) {
	/*
	 * For each fixture contacting (A and B) check if it has user data
	 * associated. In that case and only if it is the number 3 that we
	 * previously associated to our player, change isPlayerGrounded false to
	 * indicate that our player is jumping.
	 */
	Object userData = contact.getFixtureA().getUserData();
	if (userData != null && (Integer) userData == 3) {
		isPlayerGrounded = false;
		hasDoubleJump = false;
	} else {
		userData = contact.getFixtureB().getUserData();
		if (userData != null && (Integer) userData == 3) {
			isPlayerGrounded = false;
		}
	}
}
 

@Override
public void beginContact(Contact contact) {
	/*
	 * For each fixture contacting (A and B) check if it has user data
	 * associated. In that case and only if it is the number 3 that we
	 * previously associated to our player, change isPlayerGrounded and
	 * hasDobleJump variables to true.
	 */
	Object userData = contact.getFixtureA().getUserData();
	if (userData != null && (Integer) userData == 3) {
		isPlayerGrounded = true;
		hasDoubleJump = true;
	} else {
		userData = contact.getFixtureB().getUserData();
		if (userData != null && (Integer) userData == 3) {
			isPlayerGrounded = true;
			hasDoubleJump = true;
		}
	}
}
 

@Override public void endContact(Contact contact) {
    Fixture fixture = null;
    Ball ball = ballWithBody(contact.getFixtureA().getBody());
    if (ball != null) {
        fixture = contact.getFixtureB();
    }
    else {
        ball = ballWithBody(contact.getFixtureB().getBody());
        if (ball != null) {
            fixture = contact.getFixtureA();
        }
    }

    if (ball != null) {
        contactedBalls.add(ball);
        contactedFixtures.add(fixture);
    }
}
 

private boolean checkContact(Contact contact) {
    // ignore not touching contacts
    if (!contact.isTouching()) return false;

    Fixture fixtureA = contact.getFixtureA();
    if (fixtureA == null) return false;

    Fixture fixtureB = contact.getFixtureB();
    if (fixtureB == null) return false;

    Body bodyA = fixtureA.getBody();
    Body bodyB = fixtureB.getBody();

    String nameA = (String) bodyA.getUserData();
    String nameB = (String) bodyB.getUserData();

    if (nameA == null || nameB == null) {               // nameless bodies, check if sound needs to be played
        checkCollisionSound(contact, bodyA, bodyB);
        return false;
    } else if (nameA.equals(ObjectName.EDGE_SENSOR_NAME) || nameB.equals(ObjectName.EDGE_SENSOR_NAME)) {    // check edges
        Log.d(TAG, "onUpdate: OFF THE EDGE");

        setBallOut();

        return true;
    } else if (nameA.equals(ObjectName.SINKHOLE_NAME) || nameB.equals(ObjectName.SINKHOLE_NAME)) {  // check sinkhole
        Log.d(TAG, "onUpdate: SINKHOLE");

        setLevelComplete();

        return true;
    }

    return false;
}
 

@Override
public void beginContact(Contact contact) {
	Fixture fixtureA = contact.getFixtureA();
	Fixture fixtureB = contact.getFixtureB();

	/*
	 * If one of the fixture contacting is an static body, and is the wall,
	 * set ballTouchedWall to true.
	 */
	if (fixtureA.getBody().getType() == BodyType.StaticBody) {
		if (fixtureA.getBody().equals(walls)) {
			ballTouchedBox = false;
			ballTouchedWall = true;
		} else {
			ballTouchedBox = true;
			ballTouchedWall = false;
		}
	} else if (fixtureB.getBody().getType() == BodyType.StaticBody) {
		if (fixtureA.getBody().equals(walls)) {
			ballTouchedBox = false;
			ballTouchedWall = true;
		} else {
			ballTouchedBox = true;
			ballTouchedWall = false;
		}
	}
}
 

@Override
public void init(GameLevel gameLevel, PhysicsWorld physicsWorld, Engine engine) {
    _gameLevel = gameLevel;
    _physicsWorld = physicsWorld;
    _engine = engine;

    _contactListener = new ContactListenerAdapter() {
        @Override
        public void beginContact(Contact contact) {
            checkCollision(contact);
        }
    };
    _physicsWorld.setContactListener(_contactListener);
}
 

private void checkCollisionSound(Contact contact, Body bodyA, Body bodyB) {
    WorldManifold manifold = contact.getWorldManifold();
    Vector2 contactPoint = manifold.getPoints()[0];
    Vector2 vel1 = bodyA.getLinearVelocityFromWorldPoint(contactPoint);
    Vector2 vel2 = bodyB.getLinearVelocityFromWorldPoint(contactPoint);
    Vector2 impactVelocity = vel1.sub(vel2);
    float impactLen = impactVelocity.len();
    if (impactLen > MIN_BALL_SOUND_SPEED) {
        float dot = Math.abs(impactVelocity.dot(manifold.getNormal()));
        if (dot > MIN_IMPACT_SOUND_SPEED) {
            float volume = (float) Math.min((dot - MIN_IMPACT_SOUND_SPEED) / MAX_IMPACT_SOUND_SPEED, 1.0);
            SoundManager.getInstance().play(R.raw.bounce_1, volume);
        }
    }
}
 

@Override
public void beginContact(Contact contact) {
	Fixture fixtureA = contact.getFixtureA();
	Fixture fixtureB = contact.getFixtureB();

	if (fixtureA.isSensor()
			&& fixtureB.getBody().getType() == BodyType.DynamicBody) {
		buoyancyController.addBody(fixtureB);
	} else if (fixtureB.isSensor()
			&& fixtureA.getBody().getType() == BodyType.DynamicBody) {
		buoyancyController.addBody(fixtureA);
	}
}
 

@Override
public void endContact(Contact contact) {
	Fixture fixtureA = contact.getFixtureA();
	Fixture fixtureB = contact.getFixtureB();

	if (fixtureA.isSensor()
			&& fixtureB.getBody().getType() == BodyType.DynamicBody) {
		buoyancyController.removeBody(fixtureB);
	} else if (fixtureB.isSensor()
			&& fixtureA.getBody().getType() == BodyType.DynamicBody) {
		if (fixtureA.getBody().getWorldCenter().y > -1) {
			buoyancyController.removeBody(fixtureA);
		}
	}
}
 

@Override
public void beginContact(final Contact contact) {
	if (CARROT_IDENTIFIER.equals(contact.getFixtureA().getUserData())) {
		collectCarrot(contact.getFixtureA());
	} else if (CARROT_IDENTIFIER.equals(contact.getFixtureB().getUserData())) {
		collectCarrot(contact.getFixtureB());
	}
}
 

@Override
public void process (Contact contact, ContactImpulse impulse) {
	Fixture a = contact.getFixtureA();
	Fixture b = contact.getFixtureB();

	ifCarThenCollide(contact, a, b, impulse);
	ifCarThenCollide(contact, b, a, impulse);
}
 

@Override
public void beginContact(final Contact contact) {
	// Foot sensor is touching the ground
	if (FOOT_IDENTIFIER.equals(contact.getFixtureA().getUserData()) ||
			FOOT_IDENTIFIER.equals(contact.getFixtureB().getUserData()) &&
			(GROUND_IDENTIFIER.equals(contact.getFixtureA().getUserData()) ||
			GROUND_IDENTIFIER.equals(contact.getFixtureB().getUserData()))) {
		groundContacts++;
	}
}
 

@Override
public void endContact(final Contact contact) {
	if (FOOT_IDENTIFIER.equals(contact.getFixtureA().getUserData()) ||
			FOOT_IDENTIFIER.equals(contact.getFixtureB().getUserData()) &&
			(GROUND_IDENTIFIER.equals(contact.getFixtureA().getUserData()) ||
			GROUND_IDENTIFIER.equals(contact.getFixtureB().getUserData()))) {
		groundContacts--;
	}

}
 

@Override
public void postSolve(Contact contact, ContactImpulse impulse) {
}
 

@Override
public void beginContact (Contact contact) {
	// if(Box2DUtils.isCar(contact.getFixtureA()) || Box2DUtils.isCar(contact.getFixtureB()))
	// System.out.println("beginContact");
}
 

@Override
public void preSolve(Contact contact, Manifold oldManifold) {
}
 

@Override
public void postSolve(final Contact contact, final ContactImpulse impulse) {
	// TODO Auto-generated method stub
}
 

@Override
public void preSolve(final Contact contact, final Manifold oldManifold) {
	for (ContactListener listener : receivers) {
		listener.preSolve(contact, oldManifold);
	}
}
 

@Override
public void beginContact(final Contact contact) {
	for (ContactListener listener : receivers) {
		listener.beginContact(contact);
	}
}
 

public List<Contact> getContactList() {
	return this.mWorld.getContactList();
}
 

@Override
public void preSolve(final Contact contact, final Manifold oldManifold) {
	// TODO Auto-generated method stub
}
 

@Override
public void endContact(final Contact contact) {
	// TODO Auto-generated method stub
}
 

@Override
public void preSolve(final Contact contact, final Manifold oldManifold) {
	// TODO Auto-generated method stub
}
 

@Override
public void postSolve(final Contact contact, final ContactImpulse impulse) {
	// TODO Auto-generated method stub
}
 

@Override public void preSolve(Contact arg0, Manifold arg1) {
    // Not used.
}
 

@Override
public void endContact (Contact contact) {
	// if(Box2DUtils.isCar(contact.getFixtureA()) || Box2DUtils.isCar(contact.getFixtureB()))
	// System.out.println("endContact");
}
 

@Override
public void preSolve (Contact contact, Manifold oldManifold) {
}
 

@Override
public void postSolve (Contact contact, ContactImpulse impulse) {
	impactManager.process(contact, impulse);
}
 

@Override
public void endContact(final Contact contact) {
	for (ContactListener listener : receivers) {
		listener.endContact(contact);
	}
}
 

private void ifCarThenCollide (Contact contact, Fixture f, Fixture other, ContactImpulse impulse) {
	Body body = f.getBody();
	Object userData = f.getUserData();
	if ((body != null) && (userData == CarType.PlayerCar || userData == CarType.ReplayCar)) {
		Car car = (Car)body.getUserData();
		float[] impulses = impulse.getNormalImpulses();
		tmpVec2.set(impulses[0], impulses[1]);

		// dbg
		Fixture fcar = null;
		if (contact.getFixtureA().getUserData() == CarType.PlayerCar) {
			fcar = contact.getFixtureA();
		} else if (contact.getFixtureB().getUserData() == CarType.PlayerCar) {
			fcar = contact.getFixtureB();
		}

		// assumes perfect side collision
		float front_ratio = 0.5f;

		// compute median front/rear ratio for collision points
		if (fcar != null) {
			front_ratio = 0;
			float ml = car.getCarModel().length;
			float half_ml = ml * 0.5f;
			Vector2[] pts = contact.getWorldManifold().getPoints();

			int num_points = contact.getWorldManifold().getNumberOfContactPoints();
			for (int i = 0; i < num_points; i++) {
				Vector2 lp = fcar.getBody().getLocalPoint(pts[i]);

				// examine front/rear ratio
				float r = MathUtils.clamp(lp.y + half_ml, 0, ml);
				r /= ml;
				front_ratio += r;
			}

			front_ratio /= (float)num_points;
			// Gdx.app.log("Cntct", "" + front_ratio);
		}
		// dbg

		car.onCollide(other, tmpVec2, front_ratio);
	}
}