From: Steven Jones
Subject: Impossible Staircase
Date: 10 Sep 2001 16:18:36
Message: <3b9d201c@news.povray.org>
I'm trying to create my own version of the impossible staircase in Pov-ray.
Does anyone know how to work out both the horizontal and vertical angles of
a Perspective camera?
Steven Jones wrote:
> I'm trying to create my own version of the impossible staircase in Pov-ray.> Does anyone know how to work out both the horizontal and vertical angles of> a Perspective camera?
Most people use an orthographic camera for this kind of trick. There are a few
IRTC entries that use it to recreate Escher's scenes, like the impossible
waterfall.
You can use the angle keyword in your camera declaration to tell POV-Ray what
horizontal angle you want.
If you want to find the horizontal and vertical angles between any two points
in space, that's a much more difficult problem. I can post some code I've
worked out if you'd like
--
Josh English
eng### [at] spiritonecom
The POV-Ray Cyclopedia http://www.spiritone.com/~english/cyclopedia/
"Steven Jones" <ste### [at] tsncc> wrote in message
news:3b9d201c@news.povray.org...
> I'm trying to create my own version of the impossible staircase in
Pov-ray.
> Does anyone know how to work out both the horizontal and vertical
angles of
> a Perspective camera?>
Have you tried orthographic camera yet? Didn't occur to me until I saw
a post by Rico(?) in p.b.i. I couldn't figure the maths so located
camera along -z. Then rotated it <x,y,0> by "try-it-and-see" - only
took a few minutes. Use look_at to center the object. This was for a
triangle version but guess it would be just as easy for stairs.
Alf