EMAIL: wieringa@natlab.research.philips.com
NAME: Rob Wieringa
TOPIC: Physics & Math
COPYRIGHT: I SUBMIT TO THE STANDARD RAYTRACING COMPETITION COPYRIGHT.
TITLE: impossible
COUNTRY: The Netherlands
WEBPAGE: --
RENDERER USED: povray 3.0
TOOLS USED: penta (see below)
RENDER TIME: 0 hours 28 minutes 38.0 seconds (1718 seconds)
HARDWARE USED: Sun Solaris SPARC5
IMAGE DESCRIPTION:

 This image shows a physically impossible figure. It looks like three
 dumb-bell like objects, that do not touch, but are intertwined
 indissoluble.

 I have been an admirer of the Dutch graphical artist Escher (graphical
 in the classical sense, nothing to do with computer graphics ;-) ) for
 years and years, and his impossible figures intrigued me in particular.
 I discovered the one displayed here more or less by accident, and a line
 drawing (using square "toruses") has been my "logo" for a while. 

DESCRIPTION OF HOW THIS IMAGE WAS CREATED:

 When POV3 came out with the orthographic camera, I realised that this 
 impossible figure was an excellent application. As in all impossible
 figures, the camera position is essential. 
 Two of the three dumb-bells are real, the third one is a fake, and consists
 of two pieces, perfectly in line due to the camera position.
 
 The picture asked for a special color scheme.

 I exploited the "programming" facilities of POV3, and wrote a 
 general-purpose HSV to RGB converter ("colcirc.inc"). On top of that 
 comes (both for the background and for the dumb-bells) a loop that 
 generates a color map consisting of a set of color bands running through 
 (a part of) the color circle.
 These maps-loops are used in a pigment (marble with 41 colors for the 
 background, bozo with 5 colors for the dumb-bells) giving the effects 
 visible in the picture.