Re: [stella] Collision Detection

Subject: Re: [stella] Collision Detection
From: Rob <kudla@xxxxxxxxx>
Date: Thu, 26 Oct 2000 08:23:46 -0400
At 02:03 PM 10/20/00 -0700, Pete Holland wrote:
>A question occured to me after trying the game X-Man. 
>In X-Man, if you turn a corner too soon, the VCS puts
>you actually inside the playfield graphic and, since
>this is a no-no, boots you back into the aisle.  This
>costs valuable time moving around the maze.  Compare
>this to a game like Pac-Man, where the phenomena
>doesn't happen.  My question is, how is it games like
>Maze Craze and the Pac-family stop you before you hit
>the playfield graphics, and other games move you
>slightly in them and move you out again, making for
>some jerky movements?  Does the computer keep track of

I don't know about Pac-Man, but Ms. Pac-Man used two parallel sets of maze
data - one to draw the playfield, one to indicate which directions were
valid movement for each 'cell' in the maze.  (There's a bug in the code
that assumes you're using a joystick that won't let you go up and down at
the same time - it makes you go left and doesn't check that grid, so you
can end up in a wall.)  This seems like a pretty valid way to handle what
you're describing.

Doesn't surprise me too much that X-Man would be shoddily written, though
;)  The pr0n games were not really about providing a quality gaming


kudla@xxxxxxxxx ... ... Rob

Archives (includes files) at
Unsub & more at

Current Thread