; Various undocumented procedures (bad Sam!) written in CSC151

(load "/home/rebelsky/Web/Glimmer/ScriptFu/Code/gsfu.scm")

; Problem: Most people think about circles in terms of
; center and radius and not left/top/width/height

(define circle
  (lambda (image layer x y r)
    (gimp-ellipse-select image 
                         (- x r)
                         (- y r) 
                         (+ r r)
                         (+ r r)
                         REPLACE 
                         0 0 0)
    (gimp-edit-stroke layer)
    (gimp-selection-none image)))

(define select-random-brush
  (let ((num-brushes (car (gimp-brushes-list)))
        (brushes (cadr (gimp-brushes-list))))
    (lambda ()
      (gimp-brushes-set-brush (list-ref brushes
                                         (rand num-brushes))))))
                 
(define random-circle
  (lambda (image layer)
    ; Choose a color with eqch component between 0 and 255
    (gimp-palette-set-foreground (list (rand 256) (rand 256)
                                       (rand 256)))
    (select-random-brush)
    ; Radius should be less than starting point
    ; and more than 0
    ; Choose random numbers
    (circle image layer 
            (rand (car (gimp-image-width image)))
            (rand (car (gimp-image-height image)))
            (+ 10 (rand 80)))
    ))

;;; Procedure:

;;; Procedure:
;;;   random-circles
;;; Parameters:
;;;   image, the id of an image
;;;   layer, the id of a layer
;;;   num-circles, an integer
;;; Purpose:
;;;   Draws num-circles circles.
;;; Produces:
;;;   Nothing.
;;; Preconditions:
;;;   image is the id of an open image
;;;   layer is the id of a layer in that image
;;;   num-circles >= 0
;;; Postconditions:
;;;   layer contains num-circles additional circles
(define random-circles
  (lambda (image layer num-circles)
    (if (> num-circles 0)
        (begin 
          (random-circle image layer)
          (random-circles image layer (- num-circles 1))))))

;;; Procedure:
;;;   trace
;;; Parameters:
;;;   image, the id of an image
;;;   layer, the id of a layer
;;; Purpose:
;;;   Traces the image using the current color and brush
;;; Produces:
;;;   Nothing
;;; Preconditions:
;;;   image names a valid image
;;;   layer names a valid layer on that image
;;; Postconditions:
;;;   The non-background portion of the image is now traced.
(define trace
  (lambda (image layer)
    (gimp-by-color-select layer 
                          (car (gimp-palette-get-background))
                          0            ; threshold
                          REPLACE      ; operation
                          0            ; antialias
                          0            ; feather
                          0            ; feather_radius
                          0            ; sample_merged
                          )
    (gimp-selection-invert image)
    (gimp-edit-stroke layer)
    (gimp-selection-none image)))
                          REPLACE      ; operation