; Translucent Border is a script for The GIMP
;
; Creates a border with reduced brightness and 2 inner colours.
;
; The script is located in menu "<Image> / Script-Fu / Decor / Translucent Border..."
;
; Last changed: 7 August 2007
;
; Copyright (C) 2007 Harry Phillips <script-fu@tux.com.au>
;
; --------------------------------------------------------------------
;  
; Changelog:
;  Version 1.4 (7th August 2007)
;    - Added percentage as an option of border
;    - Checks if the border is too large for the image
;
;  Version 1.3 (5th August 2007)
;    - Added GPL3 licence 
;    - Menu location at the top of the script
;    - Removed the "script-fu-menu-register" section
;
;  Version 1.2
;    - Made the script compatible with GIMP 2.3
; 
; --------------------------------------------------------------------
;
; This program is free software; you can redistribute it and/or modify
; it under the terms of the GNU General Public License as published by
; the Free Software Foundation; either version 3 of the License, or
; (at your option) any later version.  
; 
; This program is distributed in the hope that it will be useful,
; but WITHOUT ANY WARRANTY; without even the implied warranty of
; MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
; GNU General Public License for more details.
; 
; You should have received a copy of the GNU General Public License
; along with this program; if not, you can view the GNU General Public
; License version 3 at the web site http://www.gnu.org/licenses/gpl-3.0.html
; Alternatively you can write to the Free Software Foundation, Inc., 675 Mass
; Ave, Cambridge, MA 02139, USA.
;
;


(define (script-fu-trans-border	theImage
				theLayer
				innerColour
				innerSize
				outerColour
				outerSize
				borderType
				borderSize
				borderPercent
				borderBrightness
	)

    (let* 
    (
	;Read the current colours
	(myForeground (car (gimp-context-get-foreground)))
	(myBackground (car (gimp-context-get-background)))

	;Read the image width and height
	(imageWidth (car (gimp-image-width theImage)))
	(imageHeight (car (gimp-image-height theImage)))
	
	(selectWidth)
	(selectHeight)
	(outerLayer)
	(innerLayer)
	(mask)
	(co-ord)
	(sizeBAD FALSE)
	(copyBack)

    )
    
    ;Calculate the selection sizes
    (if (= borderType 0)
    	;Set the co-ord to the pixel size
    	(set! co-ord borderSize)
    	
    	(begin
    		;Set the co-ord to a percentage of the shortest side
    	    (if (> imageWidth imageHeight)
	    	(set! co-ord (/ (* imageHeight borderPercent) 100))
	    	(set! co-ord (/ (* imageWidth borderPercent) 100)))
	)
    )
    
    ;Check the width
    (if (< imageWidth (+ innerSize (+ outerSize (* 2 borderSize))))
    	(set! sizeBAD TRUE)
    	())

    ;Check the height
    (if (< imageHeight (+ innerSize (+ outerSize (* 2 borderSize))))
    	(set! sizeBAD TRUE)
    	())
    
    ;Give an error message if the size is not ok
    (if (= sizeBAD TRUE)
    	(gimp-message "The image is not large enough for that border size")
    	(begin

    ;Start an undo group so the process can be undone with one undo
    (gimp-image-undo-group-start theImage)
    
    ;Copy the layer
    (set! copyBack (car (gimp-layer-copy theLayer 1)))
    
    ;Select none
    (gimp-selection-none theImage)

    ;Set the foreground and background colours
    (gimp-context-set-foreground outerColour)
    (gimp-context-set-background innerColour)

    ;Add the first layer to the image
    (gimp-image-add-layer theImage copyBack 0)

    ;Rename the layer
    (gimp-drawable-set-name copyBack "Original")

    ;Set the brightness of the background layer
    (gimp-brightness-contrast theLayer borderBrightness 0)
    
    ;Calculate the selection size
    (set! selectWidth (- imageWidth (* co-ord 2)))
    (set! selectHeight (- imageHeight (* co-ord 2)))
    
    ;Select the first part
    (gimp-rect-select theImage co-ord co-ord selectWidth selectHeight 2 0 0)

    ;Add the outer layer
    (set! outerLayer (car (gimp-layer-new theImage imageWidth imageHeight 1 "Outer" 100 0)))
    (gimp-image-add-layer theImage outerLayer 1)

    ;Fill the layer with FG colour
    (gimp-edit-fill outerLayer 0)


    ;Add a layer mask
    (set! mask (car (gimp-layer-create-mask outerLayer 4)))
    (gimp-layer-add-mask outerLayer mask)

    ;Add the inner layer(car (gimp-context-get-foreground))
    (set! innerLayer (car (gimp-layer-new theImage imageWidth imageHeight 1 "Inner" 100 0)))
    (gimp-image-add-layer theImage innerLayer 1)

    ;Fill the layer with BG colour
    (gimp-edit-fill innerLayer 1)

    ;Reduce the selection by the outer amount
    (gimp-selection-shrink theImage outerSize)

    ;Add a layer mask
    (set! mask (car (gimp-layer-create-mask innerLayer 4)))
    (gimp-layer-add-mask innerLayer mask)

    ;Reduce the selection by the inner amount
    (gimp-selection-shrink theImage innerSize)

    ;Add a layer mask to the original
    (set! mask (car (gimp-layer-create-mask copyBack 4)))
    (gimp-layer-add-mask copyBack mask)

    ;Select none
    (gimp-selection-none theImage)

    ;Set the FG and BG colours back to what they were
    (gimp-context-set-foreground myForeground)
    (gimp-context-set-background myBackground)
    
    ;Finish the undo group for the process
    (gimp-image-undo-group-end theImage)

    ;Ensure the updated image is displayed now
    (gimp-displays-flush)

    ))))


(script-fu-register "script-fu-trans-border"
            _"<Image>/Script-Fu/Misc/Translucent Border..."
            "Gives a transparent border with two inner lines"
            "Harry Phillips"
            "Harry Phillips"
            "Mar. 16 2007"
            "*"
            SF-IMAGE		"Image"			0
            SF-DRAWABLE		"Drawable"		0
            SF-COLOR		"Inner colour"		'(255 255 255)
            SF-ADJUSTMENT	_"Inner size"		'(5 0 50 1 1 0 0)
            SF-COLOR		"Outer colour"		'(0 0 0)
	    SF-ADJUSTMENT	_"Outer size"		'(5 0 50 1 1 0 0)
	    SF-OPTION		"Border type"		'("Pixels" "Percentage")
	    SF-ADJUSTMENT	_"Border pixels"	'(200 0 1000 1 1 0 0)
	    SF-ADJUSTMENT	_"Border percentage"	'(10 0 100 1 1 0 0)
	    SF-ADJUSTMENT	_"Border brightness"	'(-80 -127 0 1 1 0 1)
)