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Example Scripts

Simple Script for HDS Logos

;  HIGHLIGHT-DROP-SHADOW-LOGO
;  draw the specified text over a background with a drop shadow and a highlight

(define (color-highlight color)
  (let ((r (car color))
        (g (cadr color))
        (b (caddr color)))
    (set! r (+ r (* (- 255 r) 0.75)))
    (set! g (+ g (* (- 255 g) 0.75)))
    (set! b (+ b (* (- 255 b) 0.75)))
    (list r g b)))

(define (hds-logo text size font bg-color text-color)
  (let* ((img (car (gimp-image-new 256 256 RGB)))
         (text-layer (car (gimp-text img -1 0 0 text 10 TRUE size PIXELS "*" font "*" "*" "*" "*")))
         (width (car (gimp-drawable-width text-layer)))
         (height (car (gimp-drawable-height text-layer)))
         (bg-layer (car (gimp-layer-new img width height RGB_IMAGE "Background" 100 NORMAL)))
         (highlight-layer (car (gimp-layer-copy text-layer TRUE)))
         (shadow-layer (car (gimp-layer-new img width height RGBA_IMAGE "Shadow" 100 MULTIPLY)))
         (old-fg (car (gimp-palette-get-foreground)))
         (old-bg (car (gimp-palette-get-background))))
    (gimp-image-disable-undo img)
    (gimp-image-resize img width height 0 0)
    (gimp-image-add-layer img bg-layer 1)
    (gimp-image-add-layer img shadow-layer 1)
    (gimp-image-add-layer img highlight-layer 1)
    (gimp-palette-set-background text-color)
    (gimp-layer-set-preserve-trans text-layer TRUE)
    (gimp-edit-fill img text-layer)
    (gimp-edit-clear img shadow-layer)
    (gimp-palette-set-background (color-highlight text-color))
    (gimp-layer-set-preserve-trans highlight-layer TRUE)
    (gimp-edit-fill img highlight-layer)
    (gimp-palette-set-background bg-color)
    (gimp-drawable-fill bg-layer BG-IMAGE-FILL)
    (gimp-selection-layer-alpha img text-layer)
    (gimp-palette-set-background '(0 0 0))
    (gimp-selection-feather img 7.5)
    (gimp-edit-fill img shadow-layer)
    (gimp-selection-none img)
    (gimp-palette-set-foreground '(255 255 255))
    (gimp-blend img text-layer FG-BG-RGB MULTIPLY RADIAL 100 20 FALSE 0 0 width height)
    (gimp-layer-translate shadow-layer 3 3)
    (gimp-layer-translate highlight-layer -2 -2)
    (gimp-layer-set-name text-layer text)
    (gimp-layer-set-name highlight-layer "Highlight")
    (gimp-palette-set-background old-bg)
    (gimp-palette-set-foreground old-fg)
    (gimp-image-enable-undo img)
    (gimp-display-new img)))

Complex Script for Crystal Logos

;  CRYSTAL
;  Create a text effect that simulates crystal

(define (set-pt a index x y)
  (prog1
   (aset a (* index 2) x)
   (aset a (+ (* index 2) 1) y)))

(define (spline1)
  (let* ((a (cons-array 18 'byte)))
    (set-pt a 0 0 0)
    (set-pt a 1 31 235)
    (set-pt a 2 63 23)
    (set-pt a 3 95 230)
    (set-pt a 4 127 25)
    (set-pt a 5 159 210)
    (set-pt a 6 191 20)
    (set-pt a 7 223 240)
    (set-pt a 8 255 31)
    a))

(define (crystal-brush brush-size)
  (cond ((<= brush-size 5) "Circle (05)")
        ((<= brush-size 7) "Circle (07)")
        ((<= brush-size 9) "Circle (09)")
        ((<= brush-size 11) "Circle (11)")
        ((<= brush-size 13) "Circle (13)")
        ((<= brush-size 15) "Circle (15)")
        ((<= brush-size 17) "Circle (17)")
        (else "Circle Fuzzy (19)")))

(define (shadows val)
  (/ (* 0.96 val) 2.55))

(define (midtones val)
  (/ val 2.55))

(define (highlights val)
  (/ (* 1.108 val) 2.55))

(define (rval col)
  (car col))

(define (gval col)
  (cadr col))

(define (bval col)
  (caddr col))

(define (sota-scale val scale chrome-factor)
  (* (sqrt val) (* scale chrome-factor)))

(define (crystal-logo chrome-factor text size font bg-img env-map)
  (let* ((img (car (gimp-image-new 256 256 GRAY)))
         (back-img (car (gimp-file-load 1 bg-img bg-img)))
         (back-layer (car (gimp-image-active-drawable back-img)))
         (banding-img (car (gimp-file-load 1 env-map env-map)))
         (banding-layer (car (gimp-image-active-drawable banding-img)))
         (b-size (sota-scale size 2 chrome-factor))
         (offx1 (sota-scale size 0.33 chrome-factor))
         (offy1 (sota-scale size 0.25 chrome-factor))
         (offx2 (sota-scale size (- 0.33) chrome-factor))
         (offy2 (sota-scale size (- 0.25) chrome-factor))
         (feather (sota-scale size 0.5 chrome-factor))
         (blur (sota-scale size 0.5 chrome-factor))
         (displace (sota-scale size 0.25 chrome-factor))
         (brush-size (sota-scale size 0.5 chrome-factor))
         (text-layer (car (gimp-text img -1 0 0 text b-size TRUE size PIXELS "*" font "*" "*" "*" "*")))
         (width (car (gimp-drawable-width text-layer)))
         (height (car (gimp-drawable-height text-layer)))
         (tile-ret (plug-in-tile 1 back-img back-layer width height))
         (tile-img (car tile-ret))
         (tile-layer (cadr tile-ret))
         (bg-layer (car (gimp-layer-copy tile-layer TRUE)))
         (layer1 (car (gimp-layer-copy banding-layer TRUE)))
         (layer2 (car (gimp-layer-new img width height GRAYA_IMAGE "Layer 2" 100 DIFFERENCE)))
         (layer3 (car (gimp-layer-new img width height GRAYA_IMAGE "Layer 3" 100 NORMAL)))
         (layer-mask 0)
         (layer-mask2 0)
         (disp-map 0)
         (old-fg (car (gimp-palette-get-foreground)))
         (old-bg (car (gimp-palette-get-background)))
         (old-brush (car (gimp-brushes-get-brush))))
    (gimp-image-delete banding-img)
    (gimp-image-delete back-img)
    (gimp-image-delete tile-img)
    (gimp-image-disable-undo img)
    (gimp-image-resize img width height 0 0)
    (gimp-image-add-layer img layer3 0)
    (gimp-image-add-layer img layer2 0)
    (gimp-palette-set-background '(255 255 255))
    (gimp-selection-none img)
    (gimp-edit-fill img layer2)
    (gimp-edit-fill img layer3)
    (gimp-layer-set-visible text-layer FALSE)

    (gimp-selection-layer-alpha img text-layer)
    (gimp-palette-set-background '(0 0 0))
    (gimp-selection-translate img offx1 offy1)
    (gimp-selection-feather img feather)
    (gimp-edit-fill img layer2)
    (gimp-selection-translate img (* 2 offx2) (* 2 offy2))
    (gimp-edit-fill img layer3)
    (gimp-selection-none img)
    (set! layer2 (car (gimp-image-merge-visible-layers img CLIP-TO-IMAGE)))
    (gimp-invert img layer2)

    (gimp-image-add-layer img layer1 0)
    (gimp-layer-scale layer1 width height FALSE)
    (plug-in-gauss-iir 1 img layer1 10 TRUE TRUE)
    (gimp-layer-set-opacity layer1 50)
    (set! layer1 (car (gimp-image-merge-visible-layers img CLIP-TO-IMAGE)))
    (gimp-curves-spline img layer1 0 18 (spline1))

    (set! layer-mask (car (gimp-layer-create-mask layer1 BLACK-MASK)))
    (gimp-image-add-layer-mask img layer1 layer-mask)
    (gimp-selection-layer-alpha img text-layer)
    (gimp-palette-set-background '(255 255 255))
    (gimp-edit-fill img layer-mask)

    (set! disp-map (car (gimp-selection-save img)))
    (gimp-brushes-set-brush (crystal-brush brush-size))
    (gimp-palette-set-foreground '(0 0 0))
    (gimp-edit-stroke img disp-map)
    (gimp-selection-none img)

    (plug-in-gauss-rle 1 img disp-map blur TRUE TRUE)
    (gimp-levels img disp-map 0 0 255 1.0 96 255)

    (if (= (car (gimp-drawable-color bg-layer)) 1)
        (gimp-convert-rgb img))

    (gimp-image-add-layer img bg-layer 2)
    (set! layer2 (car (gimp-layer-copy bg-layer TRUE)))
    (gimp-image-add-layer img layer2 1)

    (plug-in-displace 1 img layer2 displace displace TRUE TRUE disp-map disp-map 0)
    (set! layer-mask2 (car (gimp-layer-create-mask layer2 BLACK-MASK)))
    (gimp-image-add-layer-mask img layer2 layer-mask2)
    (gimp-selection-layer-alpha img text-layer)
    (gimp-palette-set-background '(255 255 255))
    (gimp-edit-fill img layer-mask2)

    (gimp-selection-none img)
    (gimp-levels img layer2 0 0 200 1.5 50 255)
    (gimp-layer-set-mode layer1 OVERLAY)

    (plug-in-gauss-rle 1 img text-layer blur TRUE TRUE)
    (gimp-layer-set-preserve-trans text-layer TRUE)
    (gimp-palette-set-background '(0 0 0))
    (gimp-edit-fill img text-layer)
    (gimp-layer-set-mode text-layer OVERLAY)
    (gimp-layer-translate text-layer offx1 offy1)

    (gimp-image-remove-channel img disp-map)

    (gimp-layer-set-visible text-layer TRUE)
    (gimp-layer-set-name layer1 "Crystal")
    (gimp-layer-set-name layer2 "Interior")
    (gimp-layer-set-name bg-layer "Background")
    (gimp-layer-set-name text-layer "Shadow")

    (gimp-palette-set-foreground old-fg)
    (gimp-palette-set-background old-bg)
    (gimp-brushes-set-brush old-brush)
    (gimp-image-enable-undo img)
    (gimp-display-new img)))



Spencer Kimball
Wed May 28 22:14:48 PDT 1997