Path: utzoo!utgpu!news-server.csri.toronto.edu!cs.utexas.edu!usc!samsung!munnari.oz.au!manuel!ccadfa!prolix!dac From: dac@prolix.ccadfa.oz.au (Andrew Clayton) Newsgroups: comp.sys.amiga.graphics Subject: Re: Mandelbrot Madness Message-ID: <189c7069.ARN2850@prolix.ccadfa.oz.au> Date: 31 Jan 91 13:59:37 GMT References: <188483a4.ARN09773@prolix.ccadfa.oz.au> <1991Jan27.074838.10517@watdragon.waterloo.edu> <18986df1.ARN27d8@prolix.ccadfa.oz.au> <1991Jan29.133659.20006@zorch.SF-Bay.ORG> Reply-To: ccadfa.cc.adfa.oz.au!prolix!dac@munnari.OZ.AU Followup-To: comp.sys.amiga.graphics Organization: More like Mis~, really. Lines: 80 In article <1991Jan29.133659.20006@zorch.SF-Bay.ORG>, Kent Paul Dolan writes: > >> Wimp. It is a fact of life that, however much processing speed you > >> have, you're always going to start generating pictures that take over > >> 20 minutes. > > > Is this some 'aha' experience speaking, or a general truism that > > you've decided to espouse without using anything firm like facts? :-) > > This is the standard answer a graphics freak makes to the Luddite who tells > him he can't _possibly_ make use of any more computer power. Gee, ta, Kent. So I'm now dethroned to the rank of 'luddite'. :-) I was promised a version of a Mandelbrot program that ran on an Amdahl mainfram (IBM 3090 clone), but the guy who wrote it never released the code to me. Dammit. The pictures he was producing, even on a terrible GDDM graphics terminal, were pretty good. Even took the mainframe a deal of time to get down low, and actually broke after 5 zooms. > > Right. (512^2) * 17000 = 4.4*10^12 flops. > > Therefore you are saying that you were doing a screen a second? > > (what's 'a' flops, hmm?). A 4Gflops machine is very bloody fast. > Much too slow. If you can't do full screen resolution (preferably > 1280x1024) to the needed number of iterations (here 17,000, but pick 32K > for a nice number), at the frame rate of the display (say 60 frames per > second) then you don't have enough horsepower yet. 60FPS is overkill. You can get by with 24FPS (I guess a factor of two isn't that much to want - 1280*1024*32K*60 = 2.576*10^12 = 2,576,000,000,000 operations per second. Which is about 256 times quicker than Control Data's top of the line ETA-10 machine was capable of (10,000,000,000 FLOPS). Might take a while to acheive. :-) > > Mandebrot animations, that looked real-time (just going down seahorse > > valley, seemingly forever). > More likely took weeks to create; the universe does not yet contain > sufficent accessible computing power. -the universe- is a little overstating the point, Kent. > > I did n=4000 on MandFXP, and it just took AGES (this was in a window > > about 50 pixels by 20 pixels!). > Well, I went in to a square 1.0E-13 on a side just zooming into interesting > windows found in previous windows, and it tended to take over a day per > frame, but I can testify there's still interesting new stuff down there. > Being heavily into pain, I did this on an Apple ][+. Yuk. I climbed from the mire of Apple ][+ into Amiga, supposedly to play with graphics stuff. I even transcribed a C program to generate Mandelbrots, that took 45 minutes to do the base Mandelbrot. Sigh. Even with a 68030, it's nowhere near quick enough. (And after talking about thousand gigaflop machines, my humble 8.9Million instructions per second '30 is very weak). I went down to 1/128millionth of the screen, (lots of powers of two), saving each miniscule (1" square) picture that I created, and animating the final result. The animation "went too quick", because 'doubling' loses too much definition. I pested ASDG (Agents for CygnusSoft) to see if the guys who wrote MandFXP3.0 had released a 'movie maker' version. I got a 'no' response. :-( > > Tranputerising it would be kinda neat to see, but wasting one's life > > (and CPU) on looking at the Mandelbrot set, seems kind of a waste to > > me. C'est la vie. > The cost in electricity is small, and if you have the cpu power, and an > eye for a pleasing palette, it can be a georgeous exploration. Too repetitive. Self referential. Candy floss for the mind. > Kent, the man from xanth. Dac -- _l _ _ // Andrew Clayton. Canberra, Australia. I Post . (_](_l(_ \X/ ccadfa.cc.adfa.oz.au!prolix!dac@munnari.OZ.AU . . I am. --------------Phone +61 6 285 2537 (+10GMT) // I cannot currently send email.