//以下為知難行易的第四個材質的部分程式(波狀的地面)
//      ground plane

surf {
        spec .5 .5 .5
        fuzz 0.01
        no_antialias
        bump {
              wave {
                    center 0 0 0
                    wavelength 3.0
                    amplitude .16
                    damping .9
                    phase 0
                    }
              }

}

ring { center 0 0 0 normal 0 0 1 radius 10000 }

//     Four chinese words KNOW

surf {
           bump {
                   turb {
                           scale .5 .5 .5
                           amp .8
                           terms 1.6
                         }
                 }
             diff gold spec .7 .7 .7 shine 40
       }
//========================================================