Prof. Dr. rer. nat. Peer Johannsen

Weird Science - Tales from the Vectrex Academy Lab

Vectrex Game Project Title


Project Status

  • Final release version 2-5


  • Minimalistic Pac-Man clone in the style of the original eighties' Vectrex games
  • This project was originally meant as an educational example for the students of this course. It has somehow grown out of hand and has by now evolved into a full Vectrex game.

How To Play

  • Vec-Man lives in a maze and is always hungry. His task is to eat all the food pills that are laid out in the maze in order to advance to the next level.
  • Unfortunately, the mazes are inhabited by hostile ghosts who are also hungry and want to eat Vec-Man. If Vec-Man is caught by a ghost, he looses one of his lives.
  • With higher levels the number of ghosts will increase, and the ghosts will move faster. Also the layout of the mazes will become more and more difficult.
  • Some mazes contain power pills. If Vec-Man eats a power pill, then for a short period of time he will be able to eat the ghosts. A bonus life will be awarded if all present ghosts are eaten.


  • The intention of this project is not to recreate the original Pac-Man, but to do a Pac-Man themed clone for the Vectrex that adds slight taste of its own.
  • There are small and large mazes. In each level, the layout is different.
  • Vec-Man can take one of the outer warp exits which cause him to reappear on the  opposite site.
  • The ghosts cannot go through the outer warp exits.
  • In each maze, there are either 2, 3, 4 or 6 ghosts.
  • Each ghost has its unique strategy of chasing Vec-Man.
  • In higher levels, food pills and power pills start to move and are thus more difficult to be caught.
  • Some mazes also contain secret bonus items. Choose wisely when to use them.
  • The sequence of levels is always the same. It is created by procedural content generation techniques based on a determistic pseudo random number generator.
  • The game starts easy, but some of the much higher levels might become crazily difficult to virtually impossible...
  • The starting level can be selected as game option. However, the machine's high score will only be updated if game play is started at level 1.
  • A two player modus is available in which the players take turns.
  • The game is written entirely in C. The original Vectrex BIOS routines are used exclusively for interfacing with the Vectrex hardware.


  • Peer Johannsen


Game Play Video

Alternate Overlay Designs


  • Please read the manual before playing.
  • On initial start, the scaling of the graphics can be calibrated up to a certain degree in order to better compensate for the fact that every console has a slightly different analog behavior.
  • The game's graphics use different brightness levels. Please adjust the brightness of your console (the potentiometer on the back) so that you have a good contrast. The usual rule of thumb ("turn brightness up until the dot in the center of the screen appears, then turn it down again until that dot just vanishes") does not give the best results (vectors are too bright to give a good contrast). Turning down the brightness a bit more works better.
  • During gameplay, use button 1 to pause the game.

Regarding a physical cartridge release


  • Downloads are free and for non commercial use only. Use at your own risk.
  • Please respect the copyright and credit the author and the origin of this game.

Additional Links

Latest modification on 01/08/2020, 11:15
  • Release version 2-5 uploaded