From: John Carmack 
   Date: Mon, 21 Oct 96 09:00:37 -0500
   To: Kamil Ruszkowski 
   Subject: Re: Quake - fast or easy?
   References: 
   X-PMFLAGS: 34078848
   
   You wrote:
   
   > We've had a bit of an argument about QUAKE using floating 
   > math here in Polish USENET. Some say it is faster, some claim 
   > it is easier to
   > write for FPU and the game would be much faster using just 
   > integer.
   
   It is both faster and easier.
   
   For a 486, AMD, or cyrix cpu, quake would indeed go faster with 
   just integer ops, but not on a pentium or pentium pro.
   
   We do a LOT of multiplies in quake, and we would suffer a great
   deal if they were  blocking integer operations instead of three / 
   one cycle pipelined FP operations.
   
   Also, our inner texture mapping loop has an overlapped FP divide
   running in the background of each group of spans.
   
   People that are still resisting FP are living in the past...
   
   John Carmack