Article-I.D.: amiga.470
Posted: Thu Jan  2 22:49:50 1986
Date-Received: Sat, 4-Jan-86 06:25:06 EST
Reply-To: rj@wizard.UUCP (Robert J. Mical)
Distribution: net
Organization: Commodore-Amiga Inc., 983 University Ave #D, Los Gatos CA 95030
Lines: 50


Argh!  
In my version of Mandelbrot, I used an Intuition flag which some of you
don't "know" about yet, since it's released only with the V1.1 system.

It is the INTUITICKS flag, which is an IDCMP flag that allows you to
receive cheap, dirty timer interrupts from Intuition.  "Cheap" because
you don't have to open a timer device to get interrupts, you only
have to set a flag in the IDCMP.  "Dirty" because you'll get interrupts
*approximately* 10 times a second.  I wouldn't think of using these
interrupts for anything vaguely time-critical, since the time interval
could vary up to 75% or so.

To fix the program so that it will compile, add the following line to
the end of the mand.h file:
#define INTUITICKS  0x00400000

=RJ=

Also, while I've got your attention, here's a few presets that the
Amiga people have found (add these to the SetPresets() function near
the end of mand.c):

      case 3:
         fputs("Mandelbrot Recursion\n", console);
         start_r.f = -0.294473;
         end_r.f = -0.288444;
         start_i.f = 0.012677;
         end_i.f = 0.014839;
         color_offset = 26;
         max_count = 30;
         break;
      case 4:
         fputs("Crackle\n", console);
         start_r.f = 0.225;
         end_r.f = 0.275;
         start_i.f = 0.8425;
         end_i.f = 0.8525;
         color_offset = 61;
         max_count = 31;
         break;
      case 5:
         fputs("Connections\n", console);
         start_r.f = 0.115206;
         end_r.f = 0.168190;
         start_i.f = -1.036059;
         end_i.f = -0.985386;
         color_offset = 76;
         color_inc = 2;
         break;

Article-I.D.: uscvax.222
Posted: Wed Jan  8 00:53:45 1986
Date-Received: Thu, 9-Jan-86 06:04:39 EST
References: <470@amiga.amiga.UUCP>
Distribution: net
Organization: CS&CE Depts, U.S.C., Los Angeles, CA
Lines: 33


Great stuff these Mandelbrots! Not like on a Cray, but good enough to put on 
slides.  While compiling the latest version I came accross the following 
points:

1. line 535 of mand.c reads:
   redir_fp == NULL;
   The compiler states that this has no effect (true!). Is the correct one
   redir_fp = NULL;
   instead?

2. mand2.c prints out 11 warnings of "pointers not pointing to same object".
   These can be fixed by prepending the appropriate lines with (APTR).

3. The default values for the Mandelbrot Dragon seem a bit odd.  I found best 
  the ones from the Scientific American article (actually mirrored, since the
  function is the original one from Mandelbrot's book):

  SR = -0.5, ER = 2.0, SI = -1.25, EI = 1.25

4. Also I got stuck twice in the Analize section. No way to get out, beside 
  rebooting. I think this is a bug.


Thanks a lot for a great program.

Marco Papa
USC - Computer Science Dept.

UUCP:	...!{decvax,ucbvax,hplabs}!sdcsvax!sdcrdcf!uscvax!papa
	...!{allegra,trwrb,trwspp,ism780,cithep,oberon}!uscvax!papa
CSNET:	papa@usc-cse.csnet
ARPA:	papa%usc-cse@csnet-relay.arpa