This is a strange bug; I don't know what it is. The scaling of one object
with a material_map seems to modify the depth of the normal of another
object seen through it.

Before running the scene create an indexed png file called "test.png" for
use as the material_map.

Can anyone confirm the bug?

// It's a MegaPov bug.
// Comment out this line and the bug disappears:
#version unofficial MegaPov 0.6;

camera {location -20*z look_at 0}
light_source {<1,1,-4>*1000, color 1}

box {
   <-10,-10,0>, <10,10,1>
   texture {
      pigment {color rgb 1}
      normal {bumps 1}
      finish {phong 1}
   }
}

polygon {
   5, <1,1,0>, <-1,1,0>, <-1,-1,0>, <1,-1,0>, <1,1,0>
   texture {
      material_map {
         png "test.png"
         #declare X = 0;
         #while (X<255)
            texture {pigment {color rgb 1 transmit 1}}
            #declare X = X+1;
         #end
      }
   }

// Try to change the 0.5 below to for example
// 5 and 50 and watch the changes.

   scale <5,5,  0.5  >

   translate -z
}

Rune
--
\ Include files, tutorials, 3D images, raytracing jokes,
/ The POV Desktop Theme, and The POV-Ray Logo Contest can
\ all be found at http://rsj.mobilixnet.dk (updated December 17)
/ Also visit http://www.povrayusers.org

Post a reply to this message

In article <3a4d3d6d@news.povray.org>, "Rune" <run### [at] inamecom> 
wrote:

> This is a strange bug; I don't know what it is. The scaling of one object
> with a material_map seems to modify the depth of the normal of another
> object seen through it.

Well, since you are using MegaPOV, a possible workaround would be: don't 
use material_map, use an ordinary texture_map with image_pattern.

-- 
Christopher James Huff
Personal: chr### [at] maccom, http://homepage.mac.com/chrishuff/
TAG: chr### [at] tagpovrayorg, http://tag.povray.org/

<><

Post a reply to this message