TITLE: Gila
NAME: Douglas Eichenberg
COUNTRY: USA
EMAIL: douge@nls.net
WEBPAGE: www.getinfo.net/douge
TOPIC: The Wilderness
COPYRIGHT: I SUBMIT TO THE STANDARD RAYTRACING
JPGFILE: gila.jpg
ZIPFILE: gila.zip
RENDERER USED: 
    POVRay v3.1, MegaPOV 0.5

TOOLS USED: 
    Moray v3.2, NuGraf/PolyTrans v2.2j, Paint Shop Pro v6.02,
            MakeTree.pov by Gilles Tran, TrueSpace v4 

RENDER TIME: 
    47m 6s

HARDWARE USED: 
    600 MHz PIII/Windows 2000/128Mb


IMAGE DESCRIPTION: 
    The Sonoran Desert of Arizona, with native flora and fauna.
                   The scene depicts a Gila monster hunting for eggs.

                   GILA MONSTER:
                   There are only two known venomous lizards: the Gila Monster
                   (pictured here) and a close relative, the Mexican Beaded
Lizard.
                   Both live in the Sonoran Desert.  Both lizards are of the
same
                   genus, which dates back 30 million years to the Oligocene
epoch
                   (a period of time between the dinosaurs and man).  Over this
                   30 million year span of time, the Gila Monster has not
evolved
                   in any way; a skeleton from 30 million years ago is
identical
                   to one from the present day.  Perhaps one of the most
survivable
                   creatures, the Gila Monster is able to live up to three
years
                   without food in one of the harshest environments on the
planet.
                   They live largely on the eggs of other desert animals,
especially
                   ground nesting birds (which are quite common in the desert).
                   The Gila monster's sense of smell is so keen that it can
smell
                   a single egg buried six inches beneath the surface.

                   OCOTILLO:
                   In order for a tree or bush to survive in the desert, there
                   have to be some ingenious survival techniques.  The ocotillo
                   reduces it's exposure to harsh sunlight by shedding it's
leaves
                   when it gets to be too dry (as many as six or eight times
per
                   year).  In a place where not even weeds can grow, the
ocotillo
                   does pretty well. 

                   THE SOTOL PLANT:
                   I couldn't find anything interesting to say about this
plant,
                   except that the Pima Indians used it for weaving because it
                   has such strong fibers.

                   ROCKS:
                   In scientific terminology these are called, um, rocks. 
                  


DESCRIPTION OF HOW THIS IMAGE WAS CREATED: 

                   
                   The cracked desert floor is a height field created in POV
with
                   Moray and converted into a tileable bump map.  The beauty
                   of it is that you can't tell it's tiled unless you're
looking
                   for it.  The bump map image is a gray scale TGA.  To get the
color
                   you see I applied a semi-transparent crackle-patterned
colormap over
                   top of the bump map.  

                   The rocks came from a macro I wrote based on Jaime Vives
Piqueres
                   code for his image 'running' in the September/October '99
round
                   of the IRTC (one of my all-time favorite POV images... I use
it
                   as my Windows backdrop).  The plants are also based on code
from
                   Jaime's image.  Each plant and rock was individually placed
(ie.,
                   the placement is not random). 

                   The tree is a modified Gilles Tran tree, created with his 
                   MakeTree.pov code.  By increasing the initial number of
branch
                   segments and creating a push vector in the +y direction, I
was
                   able to create something that looked reasonably like a desert

                   bush.  

                   I came up with a neat trick for lighting the scene.  First I
                   created a simple overhead area light parallel to the ground
                   plane, making it shadowless.  I was then able to tweak this
light
                   to adjust the brightness. Then I added another area light,
tilted at 
                   an angle, to cast some nice soft shadows.  At that point I
was
                   unhappy with the overall effect; the dark areas were *too*
dark,
                   and a lot of the scene just wasn't getting enough light. 
I've
                   never liked to depend on ambience because I don't like the
                   way it looks, so what I did instead was create a large
hollow
                   sphere and make a shadowless point light, attaching the
'looks_like'
                   keyword to it.  That gave me a large spherical light all
around
                   the scene, casting light into all the little areas that were

                   otherwise missed.  It's basically a nicer version of ambient
light.
                   Moving the sphere around has some interesting and subtle
effects.
                   Also, on the area lights I turned adaptive up to 3 to smooth
out
                   the shadows.   

                   Originally, the scene was coded and rendered with version
3.1.
                   I decided at the last minute to add a motion blur effect to
the
                   tongue, so I ported the code to MegaPOV 0.5.  This had a
strange
                   effect on the bump maps and other bumps, so I added the
'#version
                   official 3.1;' line at the end of all the files.  I also had
to
                   tweak the following settings for the finish on the lizard:
ambient,
                   diffuse and specular.  The resulting leopard surface normal
looks
                   much nicer in MegaPOV than it did in version 3.1. 
Technically, 
                   this shouldn't happen: according to the MegaPOV docs, adding
the
                   '#version official 3.1;' line to the end of all the files
will
                   cause normals to be done by 3.1 methods.  Another weird
MegaPOV
                   thing: when the scene is rendered it generates a warning
saying
                   'Camera is inside a non-hollow object.' (which isn't true). 
                                                                         
                   The lizard was modelled in TrueSpace and converted to a mesh
of
                   smooth triangles with NuGraf/PolyTrans (12.6 meg file).  The
orange 
                   and black pattern on the lizards skin is an image map with a
leopard 
                   surface normal for scales.  I tried some other patterns for
the
                   normal, but none of them looked quite right. 

                   Most of the include files and image maps have been left out
because 
                   they're just too big, but I'll be happy to give a complete
copy to 
                   anybody who wants one.

