Path: utzoo!utgpu!news-server.csri.toronto.edu!rpi!usc!apple!mrspoc!starnet!sschaem From: sschaem@starnet.uucp (Stephan Schaem) Newsgroups: comp.sys.amiga.programmer Subject: Re: Lemmings - a tutorial Part V (last) Message-ID: <1991Apr6.002145.24010@starnet.uucp> Date: 6 Apr 91 00:21:45 GMT References: <1991Apr4.224045.10542@starnet.uucp> <1991Apr5.023508.17157@mintaka.lcs.mit.edu> Organization: Starnet-Public Access UNIX-Los Altos,CA 415-949-3133, login:info Lines: 24 And about that 2 cycles story... Imagine you have around 110 object to generate... After you find all the trick you could find and its not enouhgt because you have a very short time to do the job you optimize! The first time was with generation 40 SPRITES moving with path created with math structure. We now have 3 pass, and the last pass you need to creat a copper list with 6 instruction per sprites (after the sort). For sorting we came across 3 possibility.First one coded in a few minuts was VERY cycle comsuming, the second one used alot of memory. And we settle for a mix:-) Then turn out good since we reused those sorting table for fast colision with those 40 objects. Also dont forget we are in 6 plane mode, you have only 50% of the bus for you! And with a LARGE copper otside the playground screen, you have to be carefull. 4 cycle here mean 40 simple instruction... You do that a couple of time in every loop, you save ALOT. Dont forget how sprite position need to be coded:-) and we have those sprite structures cut in 2,3 parts for the hardware str and 'user str.(To port over). Untill you know what 4 cycle mean you dont care!