Hello!

Can't implement a parabolic mirror.
The scene is as follows: a parallel stream of light, a parabolic mirror (white,
in the example it is blue-red), in the focus of which is a white plate. The
camera shoots this plate from the back. I expect that the mirror will reflect
the light and the plate will be illuminated from back, but it is fully dark, and
this does not correspond to physics .. What to do?

"cmd": ["povray","$file", "+D", "+P", "+H400", "+W400", "+Fng", "+A", "+AM2",
"+Q11"],

file.pov (after test, place camera at <0,0,0>..):

#version 3.7;
global_settings{assumed_gamma 1.0}
//global_settings {ambient_light 0*<1,1,1>}
global_settings { max_trace_level 5}
#include "colors.inc"
#include "consts.inc"
#declare T=0.1;

camera {
 //orthographic
 location 2*z+2*x // must look from 'o'
 right 5*T*x
 up 5*T*y
 sky y
 look_at 0.5*z
}

// perfect parabolic mirror
parametric {
 function { u },
 function { v },
 function { u*u+v*v }
 <-1,-1>,<1,1>
 contained_by {box {<-1,-1,0>, <1,1,0.5>}}
 pigment {
  function {z}
  color_map {
   [0 color Blue]
   [1 color Red]
  }
 }
 finish{ ambient 0
   diffuse 0.5  // phong 0.5
   reflection 1
 }
}

// target
polygon { 5, <-T/2,-T/2>, <-T/2,T/2>, <T/2,T/2>, <T/2,-T/2>, <-T/2,-T/2>
  pigment{color White}
  finish { ambient 0 diffuse 1 reflection 0}
  translate 0.5*z
}

light_source {5*z color 1*White parallel point_at o} // looks_like{sphere {o,2
pigment{color Orange}}}

Post a reply to this message