Path: utzoo!utgpu!news-server.csri.toronto.edu!rpi!zaphod.mps.ohio-state.edu!think.com!snorkelwacker.mit.edu!bloom-beacon!eru!hagbard!sunic!mcsun!inesc!unl!unl!jpc From: jpc@fct.unl.pt (Jose Pina Coelho) Newsgroups: comp.sys.amiga.programmer Subject: Re: Lemmings - a tutorial Part IV Message-ID: Date: 11 Apr 91 11:57:50 GMT References: <8496@crash.cts.com> Sender: news@fct.unl.pt (USENET News System) Organization: Universidade Nova de Lisboa -- Lisbon, Portugal Lines: 49 In-Reply-To: uzun@pnet01.cts.com's message of 10 Apr 91 16:56:02 GMT In article <8496@crash.cts.com> uzun@pnet01.cts.com (Roger Uzun) writes: Yes but anything you can think of to do with a game, can be done in an OS legal manner, and since many people have A3000's,A2500's etc you cannot say any particular game will iuse 99% of the CPU. Yes, but for that the OS *must* have real-time extensions, something that will allow it to give the program all the Cpu it needs for the time it needs. The program says PrivateCPU(ON); SpeedCheck(); /* make sure you have the correct speed */ PrivateCPU(OFF); Request(time); PrivateCPU(ON); /* The game is master */ while(1) { GameCycle(); ReleaseCpu(time); /* The game is magnanimous and allow the OS to schedule other programs, but the program counter MUST be here again after time*uSeconds is elapsed */ } The point is the only thing that OS friendly and legal programming practice costs you is memory (and the time to read the RKM's etc, but given the use of source level debuggers and the enforcer,your development task is simpler if you keep the OS around) Yes, but if the OS schedules the mail spooler in the middle of a dogfight, it'll be one hell of a hiccup. Maybe on WB 3.0, we get a real time extension, to allow games to be smooth without ejecting the OS. BTW, real-time extensions are quite hard to add, they must be superbely designed to avoid constant locking. -- Jose Pedro T. Pina Coelho | BITNET/Internet: jpc@fct.unl.pt Rua Jau N 1, 2 Dto | UUCP: ...!mcsun!unl!jpc 1300 Lisboa, PORTUGAL | Home phone: (+351) (1) 640767 - If all men were brothers, would you let one marry your sister ?