Path: chuka.playstation.co.uk!news From: "Miles Buzzing" Newsgroups: scee.yaroze.programming.2d_graphics Subject: Re: Collision detection with rotating sprites Date: 3 Dec 1998 19:45:40 GMT Organization: PlayStation Net Yaroze (SCEE) Lines: 27 Message-ID: <01be1ef5$5bfd4ba0$LocalHost@guildfoc> References: <01be1d86$03a1a160$0a3ddec2@guildfoc> <742u50$9lv3@chuka.playstation.co.uk> <01be1e90$e7e94160$0a3ddec2@guildfoc> <746eq9$c3e2@chuka.playstation.co.uk> <3666DDF3.EBEFDB1E@cthullu.freeserve.co.uk> NNTP-Posting-Host: guildfrd.demon.co.uk X-Newsreader: Microsoft Internet News 4.70.1155 Yes, I've had a go with some broad tests. The method I use is less accurate that yours, but probably faster - check a bounding square based on the longest axis of the sprite first and then use a more precise bounding sphere test (using the anti-christ of fast code - Sqrt). I like bounding spheres but there is just no quick way to calculate square root as far as I can see. Even with a fixed point maths routine I still have to perform at least 12+ iterations to get an reasonable approximation of sqrt. Has anyone out there found a really quick and dirty way of calculating it? By the way, for anyone reading this who hasn't got into fixed point maths yet - do so, very quickly! For the last few years I've been used to programming PCs with powerful maths co-processors, I did some tests using floating point values on the playstation and couldn't believe how sloooooow it is - but use fixed point and it really motors! - Miles Jake Turner wrote: > How about doing simple rectangle bounding box detection first (simple > approximation) and then doing the proper tests.