TITLE: 25-01
NAME: DUVERGER Patrick
COUNTRY: France
EMAIL: patrick.duverger@sophia.cnet.fr
WEBPAGE: http://www.rez-gif.supelec.fr/home_pages/kfra/home.html
TOPIC: Physics & Math
COPYRIGHT: I SUBMIT TO THE STANDARD RAYTRACING COMPETITION COPYRIGHT.
JPGFILE: 25-01.jpg
ZIPFILE: 25-01.zip
RENDERER USED: 
    POVRAY 3

TOOLS USED: 
    none

RENDER TIME: 
    10 mn

HARDWARE USED: 
    Pentium 120

IMAGE DESCRIPTION: 
    There are three paradoxal objects which are exposed
on a marble table in a museum. These impossible objects show how
interesting it can be to by-pass physical laws of the reality within
raytraced images.
  Penrose' three beams : there are three perpendicular beams which
    finally join each other. One beam is on the z axis, another on
    the x axis, and the third on the y axis. It is impossible for
    these three beams to make a cycle : that is the optical illusion.
  Dirk Huizer' cube : the point situated in the middle of the object
    is simultaneously the center of the cube and the corner of it.
    Here is the impossibility.
  Mitsumasa Anno' construction set : each of three beam has one
    extremity which is stretched in a vertical way and its other in
    the horizontal way, that's why it is impossible to realize such
    an object.

DESCRIPTION OF HOW THIS IMAGE WAS CREATED: 
    Two different technical
tricks were used here. The 'construction set' was created simply
with a rotation of one plane of a beam in order to seem like if it
wasn't rotated. The 'Dirk Huizer cube' and the 'Penrose's three
beams' were created with elements which are situated in front of
others, but which are cut in order to fit exactly the backward
elements so that it seem they are simultaneously in the front and
in the back of the scene. The projection used to render the scene
is not the normal 3D projection, it is an isometric projection
which is obtained simply by setting big values to the coordinates
of the camera's location and direction so that the camera is very
far from the scene without seeing nothing cause of the reduction
of size. This makes rays become parallel so that the projection
become isometric. That allows tricks to be easier to render without
seeing them.