some leads..... http://members.optusnet.com.au/nickma/ProjectArchive/crasher.html gatecrasher tandy coco3 128? or 512k 2mhz 8 bit m6809 http://www.axess.com/twilight/sock/gloom/gloom.html gloom 3d a demo of the algorithum used in gatecrasher hopefully u could glean something... - Dazza