Archive for March, 2007

Travis: Trolley Dash

Friday, March 30th, 2007

travisUse the cursor keys to race your trolley around the supermarket in this Travis oriented racing game.

Postmortem:

This game was written as a development of the Unaccompanied Minors racing game, and used much the same engine underneath. The major change here is that the trolley doesn’t have to behave like a car, and as such needed to be much more slippy-slidey. The simple way to achieve that is with a basic vectored thrust and momentum movement model – something I’ve written many times over for space rocket style games in the past. It’s easy to get it feeling great for rockets (and trolleys), although it really doesn’t feel right for anything but the slipperiest of cars (think ice-racing rally cars, for example).

There are other enhancements over the Unaccompanied Minors game here too. The tracks have a clearly marked out path you can follow, so you needn’t get lost at every corner. Track design in general is much better too: There are shortcuts for the observent to find, pickups to collect for bonus points and the game runs better too due to better prepared graphics (the artist for this one followed my direction perfectly in terms of what would affect performance).

The mood of the game is a little depressing for my taste. The yellow floors and dimly lit store rooms remind me of the bad strip lighting in stores like Lidl and Aldi. That’s on purpose of course – it’s like that to fit in with the Travis song/video, but it still drags the mood down a bit for a racing game.

The biggest mistake in this game however is the collision response. It’ s much improved over Unaccompanied Minors, and you can do a lot more when you have a momentum vector hanging around that you can modify. The edge approximation still sucks however, and it’s not hard to find yourself accidentily rotated into a wall. There are all sorts of horrible special-case hacks in the code for recovering from such incidents, but luckily they don’t have to be used much, unless the player attempts some of the tighter shortcuts where it’s easier to get stuck.

Lessons:

  • Half-decent collision response still isn’t good enough!
  • Decent performance makes everything feel better
  • Everybody likes sliding around