TITLE: Uluru
NAME: Jonathon Rogers
COUNTRY: USA
EMAIL: reactor_x@hotmail.com
WEBPAGE: http://www.detrifuse.net
TOPIC: Epic Proportions
COPYRIGHT: I SUBMIT TO THE STANDARD RAYTRACING COMPETITION COPYRIGHT.
JPGFILE: j_uluru.jpg
RENDERER USED: 
    Pov-ray 3.5

TOOLS USED: 
    hf_lab for the heightfield, Photoshop for slice assembly

RENDER TIME: 
    8hours pretrace + 20hours final (approx)

HARDWARE USED: 
    P4 (HT) 3.0GHz @ 3.4GHz with 1Gb RAM and a P4 2.66GHz with 256 Mb
RAM

IMAGE DESCRIPTION: 

        Uluru is unique, a wonder of the world.  It is the largest monolith on
the face of the earth, with a circumference of nearly 6 miles.  Well over 1000
feet tall, Uluru is said to extend below the ground level to a depth of 3.5
miles.
  It plays an important part in Aboriginal mythology, and large part in the
heart of many Austrailians.


DESCRIPTION OF HOW THIS IMAGE WAS CREATED: 

        This image had a rather unique creation process due to inadequate time. 
It was my original intent to use an isosurface, but I quickly found that to be
too slow for the amount of time I had remaining.  I decided to use a
heightfield, and try to get as close as possible with careful texturing.  I
first made a blob, textured it using a black and white gradient, and rendered
it in full ambient with the hf_gray_16 switch.  This would provide me with the
basic shape of Uluru.  The heightfield was imported into heightfield lab for
editing.  After lots of playing with the flow and nsmooth commands, I was
comfortable with what I felt was a reasonable approximation of an enormous,
eroded monolith.  This was pre-rendered with no grass or clouds to capture the
radiosity data.  I began making the grass.  I couldn't decide on how I wanted
it, so I stuck with a fairly simple cone/sphere combination and used a stripped
down version of an old script I wrote for generating grass a long time ago. 
The shrubs are fairly simple "manual" sphere sweeps with random variation, and
are placed using the same technique as the grass.  The clouds are scattering
media, which is very, very sloooow...
  At this point, with little time left for the actual render, an available
laptop, and basic knowledge of how povray can behave under P4 chips with HT
(hyper threading), I split the image up into 5 slices using command line
switches, and commented out everything that was off screen (the grass eats a
LOT of RAM).  I ran two slices at a time on the 3.4GHz machine and one slice on
the other.  The render time is the total and is somewhat approxiamate, the
individual slices took anywhere from 3 to 9 hours (depending on how many clouds
were showing) and some were running concurrently.  I also wound up re-running
some of the slices with a higher sample count for the media (and still had
issues at the far right).  If all of the tracing were done on one machine, I
suspect the trace time would be about 36 hours (including radiosity
pre-tracing).
  The slice assembly and saving in jpg format were done in photoshop.  All
textures are procedural (and fairly simple).

