; FU_edges_trans-border.scm 
; version 2.8 [gimphelp.org]
; last modified/tested by Paul Sherman
; 02/03/2014 on GIMP-2.8.10
; 03/09/2020 on GIMP-2.10.20 
;
;==============================================================
;
; Installation:
; This script should be placed in the user or system-wide script folder.
;
;	Windows Vista/7/8)
;	C:\Program Files\GIMP 2\share\gimp\2.0\scripts
;	or
;	C:\Users\YOUR-NAME\.gimp-2.8\scripts
;	
;	Windows XP
;	C:\Program Files\GIMP 2\share\gimp\2.0\scripts
;	or
;	C:\Documents and Settings\yourname\.gimp-2.8\scripts   
;    
;	Linux
;	/home/yourname/.gimp-2.8/scripts  
;	
;	Linux system-wide
;	/usr/share/gimp/2.0/scripts
;
;==============================================================
;
; LICENSE
;
;    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, see <http://www.gnu.org/licenses/>.
;
;==============================================================
; Original information 
; 
; 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/Edges/Translucent Border"
; Last changed: 7 August 2007
;
; Copyright (C) 2007 Harry Phillips <script-fu@tux.com.au>
;==============================================================

(define (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 0)
            (selectHeight 0)
            (outerLayer 0)
            (innerLayer 0)
            (mask 0)
            (co-ord 0)
            (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))))
            (begin
                (set! sizeBAD TRUE)
            )
            ()
        )
        
        ;Check the height
        (if (< imageHeight (+ innerSize (+ outerSize (* 2 borderSize))))
            (begin
                (set! sizeBAD TRUE)
            )
            ()
        )
        
        ;Give an error message if the size is not ok
        (if (= sizeBAD TRUE)
            (begin
                (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-insert-layer theImage copyBack 0 0)
                
                ;Rename the layer
                (gimp-item-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-image-select-rectangle theImage CHANNEL-OP-REPLACE co-ord co-ord selectWidth selectHeight)
                
                ;Add the outer layer
                (set! outerLayer (car (gimp-layer-new theImage imageWidth imageHeight 1 "Outer" 100 0)))
                (gimp-image-insert-layer theImage outerLayer 0 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-insert-layer theImage innerLayer 0 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 "FU-trans-border"
    "Translucent Border"
    "Gives a transparent border with two inner lines. \nfile:FU_edges_trans-border.scm"
    "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"         '(150 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)
) 
           
(script-fu-menu-register "FU-trans-border" "<Toolbox>/Script-Fu/Edges/")

; end of script