Asteroids Orbital is based on the classic game Asteroids. The player pilots a ship aiming to destroy asteroids for points while also avoiding collisions to stay alive. For Orbital I introduced a black hole and the notion of gravity. All objects have a gravitational pull on each other and a ‘black hole’ in the centre sucks in both rocks and the player - he must keep himself out of the hole while destroying rocks. There are a few other changes - the player has a recovering health bar and can bounce off the rocks without instantly dying, but will take damage. The collisions are all modelled using the game physics engine. A particle system is used to illustrate the black-holes pull as well, with the particles affected by all objects’ gravity and colliding with them - speed affects their colour, which makes for an interesting effect. A replenishing timer forces the player to keep engaging the asteroids.