anchor.diff:        (cairo:rectangle  0.0d0  0.0d0 (- width 0) height)
         (cairo:set-source weapon-gradient)
   
  -      (cairo:fill)))
  +      (cairo:fill-path)))
   
   (def-texture-method ground-unit
       (with-gradient (ground-unit-gradient :radial ((/ width 2) (/ height 2)
  
positive.code:       (cairo:rectangle  0.0d0  0.0d0 (- width 0) height)
        (cairo:set-source gradient)
  
        (cairo:fill)))
  
  (def-texture-method rocket
      (let ((exhaust-scale 0.5d0))
  
negative.code:       (cairo:rectangle  0.0d0  0.0d0 (- width 0) height)
        (cairo:set-source line-gradient)
  
        (cairo:fill-path)))
  
  (def-texture-method glow
      (with-gradient (glow-gradient :radial ((/ width 2) (/ height 2)
  