dave@cs.arizona.edu (Dave P. Schaumann) (01/29/91)
Has anyone implemented the algorithm described in Appendix D of _The Science of Fractal Images_? This is the one that generates 2-color images of the Mandelbrot set very quickly. Also, what about the fractal image generator described in Appendix C of the same book? They both would be very easy to implement for someone familiar with graphics programming. All the (Pascal-ish) code is given. All that needs to be added is the system-specific stuff and a descent user interface. If no one has done either, I may have a go at one over spring break. Dave Schaumann | And then -- what then? Then, future... dave@cs.arizona.edu | -Weather Report
fhwri%CONNCOLL.BITNET@yalevm.ycc.yale.edu (01/29/91)
Nico Francois' MandelBlitz will generate the complete Mandelbrot set in
35 seconds on a 68000 Amiga in 32-color low-res. How much faster do you
want a program to get? He uses an algorithm that is, to my knowledge,
completely unique as well; all areas with the same color are bounded
(the plot goes around the area). It's quite different to watch...
--Rick Wrigley
fhwri@conncoll.bitnetdave@cs.arizona.edu (Dave P. Schaumann) (01/30/91)
The algorithm given in the book determines the minimum distance to the edge of the interior of the set, and then fills in a circle based on that calculation. Naturally, points already colored can be skipped. This leads to a great speed-up since many points can be skipped. This would be very good for exploring regions which require a high iteration value (ie >>1000). Dave Schaumann | And then -- what then? Then, future... dave@cs.arizona.edu | -Weather Report
WTW101@psuvm.psu.edu (Bill Warner) (01/30/91)
In article <43065@nigel.ee.udel.edu>, fhwri%CONNCOLL.BITNET@yalevm.ycc.yale.edu says: > >Nico Francois' MandelBlitz will generate the complete Mandelbrot set in >35 seconds on a 68000 Amiga in 32-color low-res. How much faster do you >want a program to get? He uses an algorithm that is, to my knowledge, >completely unique as well; all areas with the same color are bounded >(the plot goes around the area). It's quite different to watch... > --Rick Wrigley > fhwri@conncoll.bitnet Have you ever seen MandFXP 3.0 by Bruce Dawson and Steve LaRocque? That is the fastest mandelbrot program I have seen. It does a 320x200x5 picture at 30 iterations in about 12 seconds on a stock Amiga. Chris
Richard.Milward@samba.acs.unc.edu (Richard Milward) (01/31/91)
FYI, the public-domain FRACTINT program for the IBM-PC world has a boundary-tracing mode which does what you describe. Yes, it's quite interesting to watch... --Richard Milward / network tech / UNC-CH Ofc. of Data & Video Communications p.s. to N.C. Amigoids: Video Toaster demo this weekend! Contact Triangle Computer Society, Steve Ayscue 477-1067
WTW101@psuvm.psu.edu (Bill Warner) (01/31/91)
I uploaded MandFXP Demo version 3 to abcfd20.larc.nasa.gov because many people
were asking about it. Someone mentioned 'since the program is now public
domain, could you please upload it?'. I take this to mean that the authors
made the non-demo version public domain, but I am guessing. If this is true,
could someone please upload the non-demo version to abcfd20? Also, does anyone
know if the source code is available for this program? I'm sure many people
would be willing to pay a reasonable fee to CygnusSoft for the source code.
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Chrischem194@csc.canterbury.ac.nz (John Davis) (01/31/91)
In article <91029.231158WTW101@psuvm.psu.edu>, WTW101@psuvm.psu.edu (Bill Warner) writes: > In article <43065@nigel.ee.udel.edu>, fhwri%CONNCOLL.BITNET@yalevm.ycc.yale.edu > says: >>Nico Francois' MandelBlitz will generate the complete Mandelbrot set in >>35 seconds on a 68000 Amiga in 32-color low-res. How much faster do you >>want a program to get? He uses an algorithm that is, to my knowledge, >>completely unique as well; all areas with the same color are bounded >>(the plot goes around the area). It's quite different to watch... > > Have you ever seen MandFXP 3.0 by Bruce Dawson and Steve LaRocque? That is the > fastest mandelbrot program I have seen. It does a 320x200x5 picture at 30 > iterations in about 12 seconds on a stock Amiga. Yes, but the crucial question with both of those programs are a) what iteration limit level are they using ( I know MandelBlitz defaults to something ridiculous like itlin=150 .. way too low for anything useful ) b) what precision are they using. It's easy to get a fast mandelbrot plotter, as long as you're willing to sacrifice precision. In the end, I use Mandel (on abcfd20) to zoom around to find an interesting area, then use my own custom written program (straight m/c with inline fpu code - whole main loop sits in cache with all vars enregistered on the fpu) for high precision output (it would be fast if I wasn't having to bump itlim to >3000 to get decent looking pictures :-). Anyone know where I can get cheap 040 - I'd like to be able to get more than the 1 (640x512) screen every 1.5 hours I'm managing at the moment :-) ----------------------------------------------------------- | o John Davis - CHEM194@canterbury.ac.nz o | | o (Depart)mental Programmer,Chemistry Department o | | o University of Canterbury, Christchurch, New Zealand o | | o o | | o co-sysop AmigaINFO BBS,1200/2400 baud CCITT, o | | o 24 hours a day, ph NZ +3-3371-531 o |