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CD ROM Paradise Collection 4 1995 Nov.iso
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GEODOME
Version 1.1
Copyright (C) 1994
Andy Wardley
All Rights Reserved.
Copyright Notice:
=================
GEODOME is freely distributed software. No charge or registration fee is
required for using the program and it may be distributed by any electronic
or magnetic media providing the package is complete and unchanged.
No charge may be made for the program expect a small handling charge or
for media supplied. The program may not be sold in any other way without
the express permission of the author, Andy Wardley <abw@oasis.icl.co.uk>.
No guarantees or warranties are made with the program and the author can
accept no responsibility for any damages or losses incurred through using
this program.
Introduction:
=============
GEODOME is a utility to create data files for the POV-Ray ray tracer,
Version 2.x. It creates geodesic spheres that are created from either
triangular facets, or from a mesh of pipes and joints, depending on what
the user requires.
Usage:
======
Running GEODOME with the -h option (infact, any non-valid option) will
display a summary screen:
--
GEODOME V1.1 Geodome generator for POV-Ray V2.n 23-01-94
(C) 1994 Andy Wardley <abw@oasis.icl.co.uk>. All Rights Reserved
usage:
geodome [-r depth] [-t | -m [-p radius] [-j radius]]
-r depth recursion depth (default: 3)
-t generate triangles (default)
-m generate pipe mesh
-p radius pipe radius (mesh only) (default: 0.0100)
-j radius joint radius (mesh only) (default: 0.0150)
GEODOME may be freely distributed provided it is in its
original form and has not been modified in any way.
--
If no options are specified, a faceted geodome is created with a recursion
level (see below) of 3. The data is sent to the standard output (stdout)
and should be redirected to a file using the '>' operator.
e.g. geodome > geodome.inc
In the above example, the output is sent to a file named "geodome.inc" which
will contain something like the following (edited for clarity):
--
/* model data created by geodome V1.1 */
/* by Andy Wardley <abw@oasis.icl.co.uk> */
#declare geodome_eighth =
union {
triangle {
<0.0000000000, 1.0000000000, 0.0000000000>
<0.0000000000, 0.9807852804, 0.1950903220>
<0.1950903220, 0.9807852804, 0.0000000000>
}
[...snip...deleted to save space...]
triangle {
<0.6396021491, 0.4264014327, 0.6396021491>
<0.6396021491, 0.6396021491, 0.4264014327>
<0.4264014327, 0.6396021491, 0.6396021491>
}
}
#declare geodome_hemisphere =
union {
object { geodome_eighth }
object { geodome_eighth rotate <0, 90, 0> }
object { geodome_eighth rotate <0, 180, 0> }
object { geodome_eighth rotate <0, 270, 0> }
}
#declare geodome =
union {
object { geodome_hemisphere }
object { geodome_hemisphere rotate <180, 0, 0> }
}
--
You can then #include this file into a povray scene file and use the defined
objects "geodome_eight", "geodome_hemisphere" and "geodome" as you require.
The effective radius of the geodome is 1 unit and it is centred on the origin.
The object can be scaled and translated as required.
As GEODOME is creating the data file, a summary of what it is doing will be
displayed to standard error (stderr). It's not important to know what this
means, suffice it to say that you will still see the message even if
redirecting standard output to a file (using '>').
Options:
========
-r depth This option sets the recursion depth. If none is specified,
it defaults to 3.
GEODOME works by taking a triangle and sub-dividing it into a further 4
triangle. Each of these is then sub-divided, and so on. The recursion
depth specifies how many times this happens.
A depth of 1 means that each "side" (i.e. eighth) of the dome has 4 triangles.
Depth 2 gives 16 (4 * 4), 3 gives 64 (4 * 4 * 4), 4 gives 256, and so on.
As you can see, it's not long before the number gets very large. At high
recursion depths, it's likely you'll end up waiting a long time, assuming
that you don't run out of memory or disk space first.
-t Specifies that the geodome should be constructed from a
series of triangles. This is the default and can actually
be ignored.
-m Instructs GEODOME to create a data file consisting of pipes
(cylinders) and joints (spheres).
When the -m option is used to specify mesh mode, the -p and -j options can
be applied. If the -t option is used, the -p and -j options are ignored.
-p radius Specifies the radius of the pipes that consist the framework.
This defaults to 0.01 units.
-j radius Specifies the radius of the joints connecting the pipes.
This defaults to 0.015 units.
Examples:
=========
geodome Default operation (facets, recursion depth 3).
geodome -r 2 Create facets with recursion depth 2.
geodome -m Create a mesh (use default pipe and joint widths).
geodome -m -j 0.02 Mesh with joint radius of 0.02.
Compiling:
==========
The source code is distributed with GEODOME to allow you to compile it
for your own system. The code compiles cleanly on a SVR4 UNIX machine,
but is untested on any other system. Maths library is required and
getopts must be provided (this rules out most DOS compilers).