startshape wall background { b -.95 } rule wall { 20* { } brick { b .7 sat .5 } } rule brick .09 { ghost { } } rule brick { ghost { } brick { x 2.75 } } rule brick { ghost { } brick { x -2.75 } } rule brick { ghost { } brick { y 1.25 x (2.75/2) } } rule brick { ghost { } brick { y -1.25 x (2.75/2) } } rule brick { ghost { } brick { y 1.25 x (-2.75/2) } } rule brick { ghost { } brick { y -1.25 x (-2.75/2) } } rule ghost { SQUARE { h 0 a -.9 s 2.5 1 } } rule ghost .03 { brick { a -.87 s .707 } }