angle as float

sync on
sync rate 60

do

   cls

   inc angle
   contact(320,240,150,angle)

   sync

loop



function contact(x as integer,y as integer,size as integer,angle as float)

   ellipse x,y,size,sin(angle)*size
   ellipse x,y,sin(angle)*size,size
   ellipse x,y,sin(angle+45)*size,size

endfunction