/** Checks collisions and performs the action */
private void checkCollision() {
for (Obstacle o : obstacles) {
if (o.isColliding(player)) {
o.onCollision();
gameOver();
}
}
for (int i = 0; i < powerUps.size(); i++) {
if (this.powerUps.get(i).isColliding(player)) {
this.powerUps.get(i).onCollision();
this.powerUps.remove(i);
i--;
}
}
if (player.isTouchingEdge()) {
gameOver();
}
}
