File: gforge1c.tgz Size: 14050 bytes Date: May 28, 1995 Time: 15:00 PST Author: John Beale AuthorEmail: beale@jump.stanford.edu Uploader: John Beale UploaderEmail: beale@jump.stanford.edu Short: fractal landscape generator:1/f IFFT, 16-bit heightfields GFORGE - Graphical Fractal Forgery v0.1c jpb 5/28/95 Generates 16-bit heightfields for POV-Ray, using a high-quality algorithm: the IFFT of 1/f noise. Several parameters give you control over the appearance of the output, which can range from sand to hills to mountains. Useful also as 2D textures, and the image always tiles perfectly. Files to get: gforge*.tgz contains the C source code only. gforge*.zip includes source, DOS executable and GO32.EXE. "gforge" uses an inverse-fourier transform on 1/f filtered gaussian white noise to produce bumpy surfaces that have the appearance of realistic landscapes. "gforge" does not produce any immediate graphical images on the screen, it just writes a file for a raytracer or graphics viewer. Note the the "TGA" output is physically the standard 24-bit Targa file but in the POV-Ray heightfield format with the red and green bytes holding 16-bit grayscale, so a standard viewer will display it as green-speckled noise. PGM (Portable Grey Map) (ASCII variant) is available also, as 0-65535 integers as ascii strings. If you just want 8-bit output for viewing directly, select PG8 which is a standard 8-bit binary PGM format, which should be compatible with most viewers. All the output formats are greyscales; coloring is left up to you. For more details, see the man page. -John Beale