%% auteur : 600 setwidth 400 setheight -7 8 setxrange -5 5 setyrange %% la source d'eclairage /src {3 3 7} def /kp 8 def /f { /y exch def /x exch def 3 x mul 2 y mul add 1 add x dup mul y dup mul add neg Exp mul } def /vect_J {.7 .9} def /vect_I {1 0} def /vect_K {0 1} def %% syntaxe : nx ny (f) src_pt [color] kp x_min x_max y_min y_max surfz 100 100 (f) src [1 .65 0] kp -5 5 2 copy surfz