TITLE: Come on, dice!
NAME: Guillermo Sanz Romero
EMAIL: famrom@ran.es
WEBPAGE: http://www.geocities.com/SiliconValley/4774/               http://www.ran.es/~famrom/

TOPIC: Glass
COPYRIGHT: I SUBMIT TO THE STANDARD RAYTRACING COMPETITION COPYRIGHT.
JPGFILE: gr-lucky.jpg
ZIPFILE: gr-lucky.zip
RENDERER USED: POVRay 3.01.msdos.wat-cwa
TOOLS USED:    DOS Edit and Micrografx Picture Publisher 5.0
RENDER TIME:   22h 6m 42s
HARDWARE USED: PC i486DX2-66Mhz

IMAGE DESCRIPTION: 

"Today I feel lucky!" :D
"Throw that dice again then." :)
"Seven wins ... no more bets."


DESCRIPTION OF HOW THIS IMAGE WAS CREATED: 

This topic was hard, specially when the computer is only a 486. So I started a
list of ideas (the bimonthly list, should be named). First I tried a world
made of glass (a metaphor) but that did not convince me. The next was a
stained glass window, but after having problems with spotlights, atmosphere
and time (I thinking about a buying new computer) it was discarded too.

The final idea was two dice lying on the table: a simple but possible scene.
They are transparent plastic, but glass topic covered things that have
refraction (remember MaryAnn's message and curtopic.html).
Obviously it should be fast (not more than a day to render) but real.

First I created the die in two versions: fast (a box, for tests) and slow (a
superellipsoid), with some spheres to carve the holes. The texture was
tested many times, until the plastic appearance was real (I think it is).
The objects were easy (I must admit it), but the texture doesn't.

Then a table was made. Well, only the horizontal part and a side. The main
part is cloth with a white line to avoid "empty space" (a thin box). The side
is covered with green rubber, so I created a small pyramid and copied it with
loops (#while).

The two tokens are an intersection of a sphere and a cylinder, to obtain the
curved edge. To increase detail without distracting the observer I made a
little recess and added the metal (gold for the blue, silver for the yellow
one) numbers. These numbers are two heightfields. The texture was simple (dull
plastic) to keep the focus where it must be, the dice.

For lighting I first used one light, but then changed to one normal light
(for global light) and a smooth spotlight (to emphasize the dice). The spot
angles were calculated rendering the scene form the light's point of view, in
few test I got the angles needed for the spotlight.

The dice then were moved from the surface to the air, so they changed their
results (four and three) to a more random angle, floating a few centimeters
over the surface. But this asked for some kind of special effect to give sense
of motion. POV has not motion blur, and faking it with multiple objects will
kill my poor 486. Another solution was lens flare over the dice's highlights,
but I think they are over exploited. I needed a different effect, something
more original in computer generated images.

The final touch was to add focal blur (my first scene with it ;) ). With the
correct position of objects and camera (so perspective is noticeable), the
sense of motion was obtained. The dice seem to be frozen in the middle of a
bounce and the rest is distorted, like in racing cars' photos. This is a old
photographic technique to focus in something. Not original, but different to
the main computer images where lens flares are omnipresent.

The quality used for the final render was low, because after testing with
high quality I estimated that final render will took over seven days (too much
for me and my slow PC with its onetasking DOS), so I decided to sacrifice
quality and be able to enter the competition (seven days mean that it will end
next month, a couple of days beyond deadline).

The final picture is (IMO) a strinking one, with few things (only necessary
items), where the focus are the two frozen dice in mid-air (this is the
_Decisive_ _Moment_). When I re-install Linux and/or get a faster machine I
will render at full quality.

As is becoming usal in my scenes the aspect ratio is 16/9, which I exploit for
the sense of depth and the focal blur.
After the render ended, I used Picture Publisher to add the borders and the
text. The jpeg was created with PP5 too.

Email me if you have any question. =:)