;;; 
; The GIMP -- an image manipulation program
; Copyright (C) 1995 Spencer Kimball and Peter Mattis
;
; Quick sketch script  for GIMP 2.4
; Copyright (C) 2007 Harry Phillips <script-fu@tux.com.au>
;
; Tags: photo, artistic
;
; Author statement:
;
; Quick sketch turns a photo into what looks like a artists sketch
;
; --------------------------------------------------------------------
; Distributed by Gimp FX Foundry project
; --------------------------------------------------------------------
;   - Changelog -
; Last changed by author: 9 September 2007
; Changed on 07/03/2020 to work with Gimp 2.10.18
;
; --------------------------------------------------------------------
;
;    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/>.
;
;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;

(define (script-fu-quick-sketch-ab   theImage
                    theLayer
                    blurAmount)
    
    ;Initiate some variables
    (let* (
            (layerCopy 0)
            (layerGrey (car (gimp-drawable-is-gray theLayer)))
          )
        
        ;Start an undo group so the process can be undone with one undo
        (gimp-image-undo-group-start theImage)
        
        ;Rename the layer
        (gimp-drawable-set-name theLayer "Original")
        
        ;Select none
        (gimp-selection-none theImage)
        
        ;Change the image Greyscale if it isn't already
        (if (= layerGrey 0)
            (gimp-image-convert-grayscale theImage)
        )
        
        (set! layerCopy (car (gimp-layer-copy theLayer 1)))
        
        ;Copy the layer
        (gimp-image-insert-layer theImage layerCopy 0 0)
        
        ;Rename the layer
        (gimp-drawable-set-name layerCopy "Dodge layer")
        
        ;Invert the layer
        (gimp-drawable-invert layerCopy FALSE)
        
        ;Change the layers mode
        (gimp-layer-set-mode layerCopy 16)
        
        ;Blur the dodge layer
        (plug-in-gauss 1 theImage layerCopy blurAmount blurAmount 0)
        
        ;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-quick-sketch-ab"
        "<Image>/Script-Fu/Artistic/Quick sketch..."
        "Create a sketch from a photo. \n file:phillips-quick-skecth.scm"
        "Harry Phillips"
        "Harry Phillips"
        "Sep. 9 2007"
        "*"
        SF-IMAGE        "Image"             0
        SF-DRAWABLE     "Drawable"          0
        SF-ADJUSTMENT   "Blur factor"       '(30 5 200 1 1 0 0)
)

;end of script