(define (script-fu-domain-coloring xsize ysize function x-mid x-delta y-mid y-delta grid-delta)
   (set! img (car (gimp-image-new xsize ysize RGB)))
   (set! layer-arg (car (gimp-layer-new img xsize ysize RGBA_IMAGE "Argument" 100 NORMAL)))
   (set! layer-abs (car (gimp-layer-new img xsize ysize RGBA_IMAGE "Absolute value" 100 OVERLAY)))
   (set! layer-grid (car (gimp-layer-new img xsize ysize RGBA_IMAGE "Grid" 5 NORMAL)))

   (gimp-image-undo-disable img)
   (gimp-image-add-layer img layer-arg 1)
   (gimp-image-add-layer img layer-abs -1)
   (gimp-image-add-layer img layer-grid -1)

   (set! intro (string-append "i=ri:[0,1]; z=ri:(xy:["
			      (number->string x-mid) "," (number->string y-mid)
			      "]+xy:["
			      (number->string x-delta) "," (number->string y-delta)
			      "]*xy/XY); "
			      function ";"))

   ; interactive=0, non=1
   (plug-in-mathmap 1 img layer-arg 2 0 0.0 (string-append intro "gradient(pmod(arg(f)/2/pi,1))"))
   (plug-in-mathmap 1 img layer-abs 2 0 0.0 (string-append intro "grayColor(pmod(log(abs(f))/log(2),1))"))
   (plug-in-mathmap 1 img layer-grid 0 0 0.0 (string-append intro "tmp=xy:f/" (number->string grid-delta) "; if (floor(pmod(tmp[0],2))+floor(pmod(tmp[1],2)))%2 then grayColor(1) else grayColor(0) end"))
   (plug-in-edge 1 img layer-grid 10 0)
   (plug-in-vinvert 1 img layer-grid)

   (gimp-image-undo-enable img)
   (gimp-displays-flush)
   (gimp-display-new img))


(script-fu-register "script-fu-domain-coloring" 
      "<Toolbox>/Xtns/Script-Fu/MathMap/Domain Coloring"
      "Domain coloring of complex-valued functions"
      "Hans Lundmark"
      "Hans Lundmark"
      "2000"
      "" 
      SF-VALUE "xsize" "256"
      SF-VALUE "ysize" "256"
      SF-STRING "function" "f=sin(z*z*z-1)/z"
      SF-VALUE "x-mid"   "0.0"
      SF-VALUE "x-delta" "2.0"
      SF-VALUE "y-mid"   "0.0"
      SF-VALUE "y-delta" "2.0"
      SF-VALUE "grid-delta" "1.0")