TITLE: How do raytracers work?
NAME: Stig M. Valstad
COUNTRY: Norway
EMAIL: svalstad@sn.no
TOPIC: Magic
COPYRIGHT: I SUBMIT TO THE STANDARD RAYTRACING COMPETITION COPYRIGHT.
JPGFILE: stray.jpg
ZIPFILE: stray.zip
RENDERER USED: 
    Polyray v1.8

TOOLS USED: 
    nedit, xv, ImageMagick, dem2pov

RENDER TIME: 
    2h 32m 30s

HARDWARE USED: 
    Cyrix 686 100 Mhz w/64 MB RAM

IMAGE DESCRIPTION: 


When I heard that the subject for this round was 'Magic', I thought:
'Great subject'. Then I spent three weeks without getting any usable 
ideas. Suddenly a thought struck me: 'How do raytracers work?'. I 
know something about programming, and applying that knowledge I came 
to the conclusion that the only way they could possible work is by 
magic.

Basically it is a computer, much like mine, surrounded by objects
adapted from objects in earlier pictures I've made, floating over a
landscape, basically northern parts of Colorado, USA (the textures
are probably all wrong, still I hope for good scores from any judges
from Colorado. ;-) At the left is the much of the source code used 
for this image.


DESCRIPTION OF HOW THIS IMAGE WAS CREATED: 


First of all I made a mental image of what the final image should
look like before I did any work on the scene files. It's ended up
closer to the original mental image than my pictures usually do.

I started off making the landscape which is made from 14 DEM files
converted to TGA format with dem2pov. All these height fields 
consume vast amounts of memory, so to make it all manageable the
ones furthest away are reduced to 1/4 of original size and the ones
in the middle distance are reduced to 1/2 size with ImageMagic.

Next I collected the five objects that were to surround the computer
and refined some of the objects I was not satisfied with.

Then I started making the computer. It is mostly boxes CSGed 
together from measurements made on my own computer. The only
slightly tricky bit was the keys on the keyboard which are made
from a stretched and chopped superq object. All the keys that 
are on my keyboard are there (Each key is labeled with its
character in the scene file, except for the three Norwegian 
letters. I found that Polyray doesn't accept Norwegian letters
in comments).

Lastly I put all together, adjusting the size of all objects to
make them fit in. Lots of trial renders to adjust the positions
of everything and the lighting.

nedit was used for writing the source code, xv for screen captures,
and ImageMagick for scaling the TGA height fields and TGA to JPG
conversion.

All source code and the most important imagemaps are included.
The DEMs/height fields are not included because of the sheer size
of them, but you can find the DEMs at:
   ftp://edcsgs9.cr.usgs.gov/pub/data/DEM/250/