//light-emitting clouds
//Kurt Bangert
//http://www.travelnotes.de/
global_settings { max_trace_level 100 }
#include "colors.inc"
#include "textures.inc"

#declare fog1=
      media {
      emission .35
      density {
        spherical
        turbulence .5 
        color_map {
          [0.0 color rgb <0, 0, 0>]
          [0.3 color rgb <.1, .1, .1>]
          [0.6 color rgb <0, 0, 0>]
          [0.7 color rgb <0, 0, 0>]
          [1.0 color rgb <0, 0, 0>] }}}       
         
#declare fog2=
       media{
       emission .07
       absorption .03
       density {
        spherical
        turbulence .5 
        color_map {
          [0.0 color rgb <0, 0, 0>]
          [0.3 color rgb <.1, .1, .1>]
          [0.6 color rgb <0, 0, 0>]
          [0.7 color rgb <0, 0, 0>]
          [1.0 color rgb <0, 0, 0>] }}}    
 
//light_source { <20, 199, 58.6> color rgb<1.5,1.5,1.5> }
light_source { <0, 199, 20> color rgb<1.5,1.5,1.5> }
 
camera {location <30,48,-10>
        angle 40 look_at <30,44,50>}

//skysphere
sphere {<0,0,0>1000 hollow pigment {SkyBlue*.7}
}
  
object{sphere {<0,0,0> 1 scale <25,25,15> hollow pigment {Clear}
interior{media{fog1 scale <15,10,10>} }}  translate <50,70,200>}    

object{sphere {<0,0,0> 1 scale <100,70,100> hollow pigment {Clear}
interior{media{fog2 scale <100,30,80>} }} translate <20,25,300>}