Modeling Real-World Terrain
Terrain generated with Perlin noise looks like the following.
Because high gradients are frequent, the terrain is rough almost everywhere.
(Mouse over to scroll left or right.)
If the gradients are chosen from an exponential distribution,
then the terrain looks more natural, with rough places occurring
The source code for this paper is
available for free download from
It has been released under the
GNU All-Permissive License and contains the following notice.
If these conditions are unacceptable to you, then do not download them.
Copyright Ian Parberry, (date).
This file is made available under the GNU All-Permissive License.
Copying and distribution of this file, with or without
modification, are permitted in any medium without royalty
provided the copyright notice and this notice are preserved.
This file is offered as-is, without any warranty.
The source code is written in C++ and includes project files for Windows Visual Studio 2012
and a Unix makefile using g++.
A preliminary (and much longer) version of this paper was published
under the title
"Tobler's First Law of Geography, Self Similarity,
and Perlin Noise: A Large Scale Analysis of Gradient
Distribution in Southern Utah with
Application to Procedural Terrain Generation",
LARC Technical Report LARC-2014-04,
Laboratory for Recreational Computing, University of North Texas, June 2014.
Created June 2, 2014.
Written in HTML 4.01 and CSS 3 using vi.
Last updated May 5, 2015.