This is at heart a predator prey simulation, but during development evolved into something more of a sandbox world. It contains various interactive simulations of wind, water, rain, grass, fire, trees, numerous particles and flocking AI.

It is also capable of running genetic algorithms to determine the best animal genes to stabilise the zebra and lion populations for a given environment. This includes variables such as birth rate, hunger rate, thirst rate and more.

This is a basic video showing Predray in action. I'll upload a higher quality one soon as this is quite old and low res.

Downloadable Application


  • M - Options menu
  • Escape - Main menu
  • Left Click - Use current tool
  • Middle Click - Draw Zebras
  • Right Click - Change tool
  • Mouse Wheel - Change Tool
  • Hold Right click and drag - Change brush size