This is a quick Amiga port, done by me, of Torben Æ. Mogensen's great program "Planet"
The following is taking from the original author's "Readme":

============================================================

        Planet

    Planet generating program
    Copyright 1988-2002 Torben Æ. Mogensen
    With additions by Jim Burrows

The program generates planet maps based on recursive spatial
subdivision of a tetrahedron containing the globe (earlier versions
used a rectangular box). The output is a bitmap file, with a choice of
different formats.

============================================================


Included in this archive is the original source and data files as well as optimized
executables for the 68020, 68040, and 68060.  For demonstation I've also included two
sample pictures called A1200map.png and A1200globe.png

This map was created with the following command:

planet -s .0021 -i -0.01 -l 135 -w 800 -h 400 -ps -g 45 -G 45 -c -o A1200map.bmp

A1200globe.png was created with the same map but with orthographic projection and
bumpmapping.  A brief description of all options can be seen below.

WARNING! -- This program is CPU INTENSIVE.  A1200map.png took ~5 min to generate on
            my 50MHz 68060.

HINTS -- Experiment with low resolution images first, they take CONSIDERABLY less
         time to generate.  Once you have a map you like, then generate a high res
         version.

      -- Use the undocumented "-X" option (I found it in the source)
         This option outputs a "progress bar" to the console so you know
         the program is actually working.

If you have any questions, comments, etc about the Amiga version of this program,
please email me:

Michael A. Piva  
michpiva@shaw.ca



Usage: planet [options]

options:

  -s seed        Specifies seed as number between 0.0 and 1.0
  -w width        Specifies width in pixels, default = 800
  -h height        Specifies height in pixels, default = 600
  -m magnification  Specifies magnification, default = 1.0
  -o output_file    Specifies output file, default is standard output
  -l longitude        Specifies longitude of centre in degrees, default = 0.0
  -L latitude        Specifies latitude of centre in degrees, default = 0.0
  -g gridsize        Specifies vertical gridsize in degrees, default = 0.0 (no grid)
  -G gridsize        Specifies horisontal gridsize in degrees, default = 0.0 (no grid)
  -i init_alt        Specifies initial altitude (default = -0.02)
  -c            Colour depends on latitude (default: only altitude)
  -C            Use lighter colours (doesn't work with -a option)
  -N nocols         Use nocols number of colours (default = 256, minimum = 5)
  -a            Switch to alternative colour scheme.
  -M file        Read colour definitions from file
  -O            Produce a black and white outline map
  -E            Trace the edges of land in black on colour map
  -B            Use ``bumpmap'' shading
  -A angle        Angle of ``light'' in bumpmap shading
  -P            Use PPM file format (default is BMP)
  -x            Use XPM file format (default is BMP)
  -b            Reverse background colour (default: black)
  -V number         Distance contribution to variation (default = 0.03)
  -v number         Altitude contribution to variation (default = 0.4)
  -pprojection        Specifies projection: m = Mercator (default)
                      p = Peters
                      q = Square
                      s = Stereographic
                      o = Orthographic
                      g = Gnomonic
                      a = Area preserving azimuthal
                      c = Conical (conformal)
                      M = Mollweide
                      S = Sinusoidal
                      h = Heightfield
                      f = Find match, see below

 PERMSSN    UID  GID    PACKED    SIZE  RATIO     CRC       STAMP          NAME
---------- ----------- ------- ------- ------ ---------- ------------ -------------
[generic]               210976  210976 100.0% -lh0- 8a67 Jan  1  1980 Planet/A1200globe.png
[generic]               173196  173196 100.0% -lh0- 883c Jan  1  1980 Planet/A1200map.png
[generic]                 1710    4041  42.3% -lh5- ac0d Jan  1  1980 Planet/Amiga.readme
[generic]                 1842    2781  66.2% -lh5- bdc0 Jan  1  1980 Planet/Amiga.readme.info
[generic]                  467     830  56.3% -lh5- bd0f Apr 20  2005 Planet/Makefile
[generic]                 6844   17207  39.8% -lh5- ebaa Aug 14  2002 Planet/Manual.txt
[generic]                  124     275  45.1% -lh5- a340 Apr 23  2003 Planet/map5
[generic]                   51      72  70.8% -lh5- ef4a Jun 27  2002 Planet/Mars.rgb
[generic]                66871  178072  37.6% -lh5- 0830 Apr 20  2005 Planet/planet.020
[generic]                70087  173928  40.3% -lh5- 5932 Apr 20  2005 Planet/planet.020fpu
[generic]                62016  148512  41.8% -lh5- 6b11 Apr 20  2005 Planet/planet.040
[generic]                61646  147184  41.9% -lh5- 6419 Apr 20  2005 Planet/planet.060
[generic]                14707   64339  22.9% -lh5- ea90 Aug 31  2004 Planet/planet.c
[generic]                  862    1767  48.8% -lh5- b3aa Aug 14  2002 Planet/ReadMe
[generic]                   47      72  65.3% -lh5- 485e Jun 27  2002 Planet/Yellow.rgb
---------- ----------- ------- ------- ------ ---------- ------------ -------------
 Total        15 files  671446 1123252  59.8%            Apr 23  2005