// sky ---------------------------------------------------------------
// sky textures --------------------------------------------------------
#declare T_Clouds  =
texture {
    pigment { bozo
        turbulence 1.5
        octaves 10
        omega 0.5
        lambda 2.5
        color_map { [0.0 color rgbf<1, 1, 1, 1> ]
                    [0.2 color rgbf<0.85, 0.85, 0.85, 0.00>*1.5 ]
                    [0.5 color rgbf<0.95, 0.95, 0.95, 0.90>*1.12  ]
                    [0.6 color rgbf<1, 1, 1, 1> ]
                    [1.0 color rgbf<1, 1, 1, 1> ] }
    }

    finish {ambient 0.95 diffuse 0.1}
}

//--------------------------------------------------------------------
union { // make sky planes: 

 plane { <0,1,0>, 500 hollow //!!!!
        texture { bozo scale 1
                  texture_map{ 
                       [ 0.0  T_Clouds ]
                       [ 0.5  T_Clouds ]
                       [ 0.6  pigment{color rgbf<1,1,1,1> }] 
                       [ 1.0  pigment{color rgbf<1,1,1,1> }] 
                      } 
                       scale <500,1,1000>} translate<-400,0,300> } 

 plane { <0,1,0> , 10000  hollow
        texture{ pigment {color rgb<0.24,0.38,0.7>*0.50}
                 finish {ambient 1 diffuse 0}}}
scale<1.5,1,1.25>  
rotate<0,0,0> translate<0,0,0>}                          // end of sky
//--------------------------------------------------------------------

// fog on the ground -------------------------------------------------
fog { fog_type   2
      distance   50
      color      rgb<1,1,1>*0.75
      fog_offset 0.1
      fog_alt    1.5
      turbulence 1.8
    }
//-----------------------------------------------// end of ground fog
//--------------------------------------------------------------------