TITLE: 9-Ball
NAME: Bob Franke
COUNTRY: USA
EMAIL: wordsltd@halcyon.com
WEBPAGE: none
TOPIC: Math and Physics
COPYRIGHT: I SUBMIT TO THE STANDARD RAYTRACING
JPGFILE: 9ball.jpg
ZIPFILE: 9ball.zip
RENDERER USED: 
    Povray 3.01

TOOLS USED: 

  PhotoStyler to add the copyright note and process the blackboard text
  POV-Ray for Windows, Version 3.01  for coding and rendering


RENDER TIME: 
    7 hours 32 minutes


HARDWARE USED: 

  A generic Pentium 133 with 48 Mb's of ram
  HP ScanJet 4p
  HP calculator
  A beer bottle
  Some black paper
  A piece of white chalk



IMAGE DESCRIPTION: 

While developing the concept for this image, a
friend recalled a time in college when two
physics students were late for class because
they were playing pool.  They claimed to have
lost track of time while conducting experiments
in kinetic energy, and its conservation, with
colliding objects.  The professor then replied
"oh, you were playing pool again."

In my image, the professor solves this problem
by conducting class in the pool hall.  We are
looking over his shoulder, as he is about to
demonstrate the theory on the blackboard, by
attempting a game winning combination shot on
the nine ball.

As with most classic problems in physics, the
concepts on the blackboard are true if friction
is ignored.  In real life, the math has been
shown to be off by about 2 percent.  If the
player adds additional spin to the que ball,
you may as well just throw the equations out
the window.

If you care to learn a little more about the
physics and the physics of pool, check out
URL's:
http://aci.mta.ca/TheUmbrella/Physics/P3401/Investigations/BilliardCollREC.html
http://www.wsu.edu:8000/~heythere/phssci.html
http://www.chem.wsu.edu/phs298/KinPotEn.html#kin




DESCRIPTION OF HOW THIS IMAGE WAS CREATED: 

Everything in the image is to scale. One unit
equals one inch.

The scene is illuminated five perimeter area
lights and three spotlights directly over the
table.

The image maps for the blackboard were created
by writing the text on black paper with white
chalk.  This was then scanned with the ScanJet 4p
and saved as Targa files.

A separate include file, poolball.inc, was made
for the pool balls.  To create a poolball just
declare the RGB values for bRed, bGreen,bBlue,
declare solidBall= True or False, declare
BallNumber = "1" and declare TextX = .15 (to
locate the ball number in the spot).  Then
provide the include statement for poolball.inc
and you have a poolball.

To make it easier to vary the color of the
handle, a turned the questick into an include
file.  The questick is constructed of
cylinders, cones, a sphere, many tori for the
handle and a couple of superellipsoid's for the
tip.

The lathe object for the beer bottle is also an
include file.  To get the data points for the
profile of the bottle, I simply scanned one
with the ScanJet 4p.  I then used Photostyler
to measure the data points.  After a couple of
tries, a gave up on trying to remove both
labels from the bottle.  I did manage to remove
the small one from the neck, for scanning.  The
larger label was found on a web page.  Some of
you can no doubt tell what beer I drink.

Everything is made with simple constructive solid
geometry, while loops, and the trig math
functions.  However, I am developing a special
appreciation for the superellipsoid object.  It
has come to my rescue several times.