;; -*-scheme-*-

;; Land --- create a pattern that resembles a Topographic map
;; Copyright (C) 1997 Adrian Karstan Likins.  <aklikins@eos.ncsu.edu>
;; Thanks to Frederico Mena Quintero (Quartic) for helping me debug this. 
;;
;; 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-pattern-land image drawable seed randomise detail land-height sea-depth x-scale y-scale gradient use-current-gradient)
    ;; make the effect undoable
    (gimp-image-undo-group-start image) 
    
    ;; save current gradient 
    (set! gradient-saved (car (gimp-gradients-get-gradient))) 

    ;; use the gradient specified by this script? 
    (if (= use-current-gradient FALSE) (gimp-gradients-set-gradient gradient))

    ;; randomise, ignore input seed.  use randomely generated seed instead
    (if (= randomise TRUE) (set! seed (rand 65536)) )  

    ;; copy the original layer or selection to a new layer
    (gimp-edit-copy drawable) 
    ;; set this as layer one, even if it is not a proper layer yet
    (set! layer-1 (car (gimp-edit-paste drawable FALSE))) 
    (gimp-floating-sel-to-layer layer-1) ;; but it is now
    ;; dont want a layer called "Pasted Layer", so change it
    (gimp-drawable-set-name layer-1 _"Noise Layer") ; not v1.2 compatible

    (set! turbulent TRUE)
    (set! tileable TRUE)
    (plug-in-solid-noise 1 image layer-1 turbulent tileable seed detail x-scale y-scale)
    (plug-in-c-astretch 1 image layer-1)

    ;; copy layer-1 to create layer-2
    (set! layer-2 (car (gimp-layer-copy layer-1 TRUE)))
    (gimp-image-add-layer image layer-2 -1)
    (gimp-drawable-set-name layer-2 _"Land Layer") ; not v1.2 compatible

    ; this is not actually necessary, layer-2 was the last used and still active
    (gimp-image-set-active-layer image layer-2)
    ; map (overdraw using) the coloured gradient
    (plug-in-gradmap 1 image layer-2)

    (gimp-by-color-select layer-1 '(190 190 190) 55 REPLACE FALSE FALSE 0 FALSE)
    (plug-in-bump-map 1 image layer-2 layer-1 135.0 35 land-height 0 0 0 0 TRUE FALSE 0)

    ;(plug-in-c-astretch 1 image layer-2)
    (gimp-selection-invert image)
    (plug-in-bump-map 1 image layer-2 layer-1 135.0 35 sea-depth 0 0 0 0 TRUE FALSE 0)

    ;(plug-in-c-astretch 1 image layer-2)

    ;; merge/remove? I prefer merge when using a mostly transparent gradient
    ;; results are more interesting and consistant with the old version of the script
    ;(gimp-image-remove-layer image layer-1) ; remove it 
    ;(gimp-image-merge-down image layer-2 0) ; merge it

    ;; (un)comment the next line if you do (not) want to keep a selection of the "land"
    (gimp-selection-none image) 
    
    ;; restore gradient
    (gimp-gradients-set-gradient gradient-saved) 

    (gimp-image-undo-group-end image)  
    (gimp-displays-flush)
)


(script-fu-register "script-fu-pattern-land"
    _"<Image>/Filters/Render/Pattern/Land..." ; put in menus with other patterns
    "Create a Topographic map pattern.  

Recommended gradients: 
'Land' gradient produces a landscape that looks like Earth.  
'Brushed_aluminum' gradient produces a landscape that looks like the Moon.  
'Browns' gradient produces a landscape that looks like Mars.  
"
    "Alan Horkan.  Adrian Karstan Likins.  "
    "Alan Horkan.  Adrian Karstan Likins.  "
    "2004 04 02" ; UTC format Dates.  
    "RGB*" 
    SF-IMAGE "Image" 0
    SF-DRAWABLE "Drawable" 0
    SF-ADJUSTMENT _"Random Seed" '(42 0 99999999 1 10 0 1) ; seed can be any INT32
    SF-TOGGLE _"Randomise" FALSE
    SF-ADJUSTMENT _"Detail" '(4 0 15 1 5 0 0) ; detail must be 0-15
    SF-ADJUSTMENT _"Land Height" '(60 1 65 1 10 0 0)
    SF-ADJUSTMENT _"Sea Depth" '(4 1 65 1 10 0 0)
    SF-ADJUSTMENT _"Scale X" '(4 0.1 16 1 5 0.1 0)
    SF-ADJUSTMENT _"Scale Y" '(4 0.1 16 1 5 0.1 0)
    SF-GRADIENT   _"Gradient" "Land 1" ;; was "Land_1" in version 1.2
    SF-TOGGLE   _"Use Current Gradient" FALSE
)

;; ALAN: rewrote script to work on current image
;; ALAN: added Undo support
;; ALAN: rewrote even more to work on current selection (or not)
;; ALAN: added save and restore of current gradient 
;; ALAN: added option use current gradient
;; ALAN: ported to 2.0 but kept the 1.2 information in comments.   
;; ALAN: later split out the deprecated v1.2 information

;; Question: How much code can be reused as just fair use?  
;; How much code must be rewritten for the GPL to no longer apply?  
;; My work should be considered public domain, 
;; Ask previous authors about licensing not me.