POV-Ray : Newsgroups : povray.binaries.images : Unrolled : Re: Unrolled Server Time
16 Aug 2024 18:21:44 EDT (-0400)
  Re: Unrolled  
From: Batronyx
Date: 11 Jan 2002 15:11:46
Message: <3c3f4702@news.povray.org>
"Tor Olav Kristensen" <tor### [at] hotmailcom> wrote in message
> Can you explain a little bit more about
> what you are doing ?

Sure.

>
> Are you "moving" around a mesh on the
> surface of a cylinder and recalculating
> 3 coordinates relative to the 2D-surface
> of the cylinder ? And thereafter regene-
> rating the whole surface with these new
> coordinates. ?

Nothing that complicated. The net result is the same but it isn't limited to
meshes. I just take an object and use image_width + 1 number of copies. Each is
rotated 1/image_width degrees and has a 1 pixel wide slice taken from it (using
three intersecting planes as a clipped_by object) and translated into place. The
extra copy is because I leave the clipping object centered, so half the pixel is
on one side and half on the other.

All of this was entirely possible with 3.1, however, the new 3.5 min/max_extents
and image_width/height keywords make it much more convenient. Just include your
object file and declare it as the 'Wrapobject'(see scene file in p.b.s-f),
modify the texture if desired, and it will automatically be sized to fit from
top-to-bottom, then unwrapped.

As is, there are no lights because I like ambient 1 gradients for such things,
but you could certainly add some if desired.

--
light_source{0,1}#macro c(J,a)sphere{0,1pigment{rgb z}scale a translate J+O}
#end#macro B(R,V,O)c(0,4)intersection{c(V,R)difference{c(-z*4x+10)c(-z*4.1x+
10)c(0<7.5,45,5>)}}#end B(12,0z*25)B(8y*4<0,12,50>)          // Batronyx ^"^


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