; The GIMP -- an image manipulation program
; Copyright (C) 1995 Spencer Kimball and Peter Mattis
; 
; Explode via Transparent Layer 
; Copyright (c) 2000-2004 Matteo Nastasi aka mop
; nastasi@alternativeoutput.it
; matteo.nastasi@milug.org
;
; Take all layers with particular prefix, put disable everyone of this,
; and to loop for enable one to one, copy the image, crop and save it
; with the name of layer.
;
;
; 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 2 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, write to the Free Software
; Foundation, Inc., 675 Mass Ave, Cambridge, MA 02139, USA.


(define (script-fu-mop-im-explode-via-transplay img drw pref type path)
; disable undo
  (gimp-image-undo-disable img)
; number of char in prefix
  (set! char-num (string-length pref))
; extract number and array of layer
  (set! layarray (gimp-image-get-layers img))
  (set! nlay (car layarray))
  (set! lay-arr (cadr layarray))
  (set! ct 0)
  (set! i 0)
  (while (< i nlay) 
	 (set! curlay (aref lay-arr i))
	 (set! namelay (car (gimp-layer-get-name curlay)))
	 (if (equal? (substring namelay 0 char-num) pref)
	     (begin
	       ; if layer start with pref dup image and save only this active
	       (set! nw-img (car (gimp-channel-ops-duplicate img)))
               (set! nw-layarray (gimp-image-get-layers nw-img))
               (set! nw-lay-arr (cadr nw-layarray))
               (set! nw-ct 0)
	       (set! nw-i 0)
	       (while (< nw-i nlay)
		      (set! nw-curlay (aref nw-lay-arr nw-i))
		      (if (= nw-i ct)
			  (begin
			    ;			    (gimp-image-set-active-layer nw-img nw-curlay)
			    (gimp-layer-set-visible nw-curlay TRUE)
			    (set! nw-w (car (gimp-drawable-width nw-curlay)))
			    (set! nw-h (car (gimp-drawable-height nw-curlay)))
			    (set! offsets (gimp-drawable-offsets nw-curlay))
			    (set! nw-x (car  offsets))
			    (set! nw-y (cadr offsets))
			    )
			  (begin
			    ;    (gimp-image-set-active-layer nw-img nw-curlay)
			    (set! nw-namelay (car (gimp-layer-get-name nw-curlay)))
			    (if (equal? (substring nw-namelay 0 char-num) pref)
				(gimp-layer-set-visible nw-curlay FALSE)
				)
			    ))
		      (set! nw-i (+ nw-i 1))
		      )
	       ; (gimp-image-merge-visible-layers nw-img 0)
	       (gimp-crop nw-img nw-w nw-h nw-x nw-y)
	       (set! fla (car (gimp-image-flatten nw-img)))
	       ; (gimp-message (string-append namelay "." type))
	       (set! namelen (string-length namelay))
	       (set! namefile (string-append path "/" (substring namelay 
							char-num namelen) 
					     "." type))
	       (gimp-file-save 1 nw-img fla namefile namefile)
	       (gimp-image-delete nw-img)
	       ; (gimp-display-new nw-img)
	       (set! ct (+ ct 1))
	       )
	     )
	 (set! i (+ i 1))
	 ) ; end of while
  (gimp-image-undo-enable img)
  )
	  
(script-fu-register "script-fu-mop-im-explode-via-transplay"
		    "<Image>/Script-Fu/MOP/Explode via Trasp Lay"
		    "Convert a selection to a new transparent layer"
		    "Matteo Nastasi <matteo.nastasi@milug.org>"
		    "Matteo (aka mop) Nastasi"
		    "09/11/2000"
		    "RGB RGBA GRAY GRAYA"
		    SF-IMAGE "Image" 0
		    SF-DRAWABLE "Drawable" 0
                    SF-STRING "Prefix" "SUB_"
		    SF-STRING "Extension" "pnm"
                    SF-FILENAME "Path"       ".")