/* -------------------------------------------------------------*/ private void objectCollision(ArrayList movingObjects) { for (int i = 0; i < movingObjects.size(); i++) { // make sure not testing if collided with yourself :P if (((SpaceObject) movingObjects.get(i)).getObjCount() != objectNum) { SpaceObject object = (SpaceObject) movingObjects.get(i); // find distance vector between two objects int x = pos_x - object.getXPos(); int y = pos_y - object.getYPos(); double distance = Math.sqrt(x * x + y * y); // has it collided with the object? if (distance < (radius + object.getRadius())) { // has it collided with a BULLET (or MISSILE)? if (object.isBullet()) { // do nothing } // is it another SPACESHIP? (INSTANT DEATH) else if (object.isSpaceShip()) { // do nothing } // collided with anything else (e.g PLANET): (INSTANT DEATH) else { collision.play(); kill(movingObjects); // object has died } } } } // end for loop }
/* -------------------------------------------------------------*/ private void gravityEffect(ArrayList movingObjects) { // find effect of gravity on this objects from all other objects for (int i = 0; i < movingObjects.size(); i++) { // reset variables double add_vx = 0.0; double add_vy = 0.0; SpaceObject object = (SpaceObject) movingObjects.get(i); if (object.getObjCount() != objectNum && // ignore yourself (distance = 0!) !object.isBullet() && // ignore bullets !object.isSpaceShip()) // ignore spaceships { // find distance vector between planet and ball int x = pos_x - object.getXPos(); int y = pos_y - object.getYPos(); double distance = Math.sqrt(x * x + y * y); // find effect of planet on velocity double add_vec = (SpaceObject.G * k * object.getMass() * ballMass) / (distance * distance); add_vx = -(x / distance) * add_vec; add_vy = -(y / distance) * add_vec; // add objects speeds onto spaceship speed (clip speed if too large) x_speed += add_vx; y_speed += add_vy; } } }
/** Gets volatility for given instrument. */ public double calculate(final Instrument instrument) { final double[] values = this.getValues(instrument); return Math.sqrt(this.variance.evaluate(values)); }