; 210_effects_crosslight.scm
; last modified/tested by Paul Sherman [gimphelp.org]
; Thursday, 07/02/2020 on GIMP 2.10.20
;==================================================
;
; Installation:
; This script should be placed in the user or system-wide script folder.
;
;	Windows 7/10
;	C:\Program Files\GIMP 2\share\gimp\2.0\scripts
;	or
;	C:\Users\YOUR-NAME\AppData\Roaming\GIMP\2.10\scripts
;	
;    
;	Linux
;	/home/yourname/.config/GIMP/2.10/scripts  
;	or
;	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 
; 
; Cross light script  for GIMP 2
; based on Cross light script  for GIMP 1.2
; Copyright (C) 2001 Iccii <iccii@hotmail.com>
; 
; --------------------------------------------------------------------
; version 0.1  by Iccii 2001/07/22
;     - Initial relase
; version 0.2  by Iccii 2001/08/09
;     - Add the Start Angle and the Number of Lighting options
; version 0.2a adapted for GIMP2  by EV
;==============================================================
(define (210-cross-light
		img
		drawable
		length
		angle	
		number
		threshold
		inMerge
	)
	(gimp-image-undo-group-start img)
	(if (not (= RGB (car (gimp-image-base-type img))))
			 (gimp-image-convert-rgb img))
  (let* (
	(modulo fmod)			;; in R4RS way
	(count 1)
	(tmp-layer (car (gimp-layer-copy drawable TRUE)))
	(target-layer (car (gimp-layer-copy drawable TRUE)))
	(layer-mask (car (gimp-layer-create-mask target-layer ADD-MASK-WHITE)))
	(marged-layer (car (gimp-layer-copy drawable TRUE)))
	(currentselection (car(gimp-selection-save img)))
	)
;    (set! currentselection (car(gimp-selection-save img)))
	(gimp-selection-none img)
	(gimp-image-insert-layer img target-layer 0 -1)
	(gimp-layer-add-mask target-layer layer-mask)
	(gimp-image-insert-layer img tmp-layer 0 -1)
	(gimp-desaturate tmp-layer)
	(gimp-threshold tmp-layer threshold 255)
	(gimp-edit-copy tmp-layer)
    (gimp-floating-sel-anchor (car (gimp-edit-paste layer-mask 0)))
    (gimp-layer-remove-mask target-layer MASK-APPLY)
    (gimp-drawable-fill tmp-layer 3)
    (gimp-image-set-active-layer img target-layer)
    (while (<= count number)
      (let* (
             (layer-copy (car (gimp-layer-copy target-layer TRUE)))
             (degree (modulo (+ (* count (/ 360 number)) angle) 360))
            )
        (gimp-image-insert-layer img layer-copy 0 -1)  
        (if (= count 1) (gimp-image-raise-item img layer-copy)) 
        (plug-in-mblur 1 img layer-copy 0 length degree 0 0); two argyuments added for GIMP2  by EV       
        (set! marged-layer (car (gimp-image-merge-down img layer-copy 0 )))
        (gimp-item-set-name marged-layer "cross-light") ; this line was added by EV
        (set! count (+ count 1))
      ) ; end of let*
    ) ; end of while
    (gimp-image-remove-layer img target-layer)
    (gimp-layer-set-opacity marged-layer 80)
    (gimp-layer-set-mode marged-layer SCREEN-MODE)
    (gimp-image-select-item img CHANNEL-OP-REPLACE currentselection) ; these five lines are new in version 0.6a
    (if (equal? (car (gimp-selection-is-empty img)) FALSE) 
        (begin
        (gimp-selection-invert img)
        (if (equal? (car (gimp-selection-is-empty img)) FALSE) (gimp-edit-fill marged-layer 3))
        (gimp-selection-invert img)
        ))
    (gimp-image-remove-channel img currentselection)
	(if (= inMerge TRUE)(gimp-image-merge-visible-layers img EXPAND-AS-NECESSARY))
    (gimp-image-undo-group-end img)
    (gimp-displays-flush)
  )
)
(script-fu-register
	"210-cross-light"
	"Cross Light"
	"Cross light effect - sort of a random criss-cross of speculars."
	"Iccii <iccii@hotmail.com>"
	"Iccii"
	"2001, Aug"
	"*"
	SF-IMAGE      "Image"									0
	SF-DRAWABLE   "Drawable"								0
	SF-ADJUSTMENT "Light Length"							'(40 1 255 1 10 0 0)
	SF-ADJUSTMENT "Start Angle"								'(30 0 360 1 10 0 0)
	SF-ADJUSTMENT "Number of Lights"						'(4 1 16 1 2 0 1)
	SF-ADJUSTMENT "Threshold (Bigger 1<-->255 Smaller)"  	'(223 1 255 1 10 0 0)
	SF-TOGGLE     "Merge layers when complete?" 			FALSE
)
(script-fu-menu-register "210-cross-light" "<Image>/Script-Fu/Effects")