(define (sg-fuzzy-select-along-path image path operation antialias? feather? radius transparent? merged? thresh criterion)
  (let* (
      (x1 0)
      (y1 0)
      (x2 (car (gimp-image-width image)))
      (y2 (car (gimp-image-height image)))
      (stroke's (vector->list (cadr (gimp-vectors-get-strokes path))))
      (stroke nil)
      (point nil)
      (x 0)
      (y 0)
      (last-x 0)
      (last-y 0)
      (dist 0)
      (source 0)
      (orig-sel 0)
      )
    (set! source (car (gimp-image-get-active-drawable image)))
    (set! orig-sel (car (gimp-selection-save image)))
    (gimp-selection-none image)
    (when (= merged? FALSE)
      (set! x1 (car (gimp-drawable-offsets source)))
      (set! y1 (cadr (gimp-drawable-offsets source)))
      (set! x2 (+ x1 (car (gimp-drawable-width source))))
      (set! y2 (+ y1 (car (gimp-drawable-height source))))
      )
    (while (pair? stroke's)
      (set! stroke (car stroke's))
      (set! dist (car (gimp-vectors-stroke-get-length path stroke 0.5)))
      (while (>= dist 0) 
        (set! point (gimp-vectors-stroke-get-point-at-dist path stroke dist 1))
        (set! x (truncate (car point)))
        (set! y (truncate (cadr point)))
        (when (and (or (<> x last-x) (<> y last-y)) (= (cadddr point) 1))
          (when (and (>= x x1) (>= y y1) (< x x2) (< y y2))
            (set! last-x x)
            (set! last-y y)
            (when (and (= merged? FALSE))
              (set! x (- x x1))
              (set! y (- y y1))
              )
            (gimp-fuzzy-select-full source 
                                    x y 
                                    thresh
                                    CHANNEL-OP-ADD
                                    antialias? 
                                    feather? radius radius
                                    merged? transparent? criterion)
            )
          )
        (set! dist (- dist 1))
        )
      (set! stroke's (cdr stroke's))
      )
    (gimp-channel-combine-masks orig-sel (car (gimp-image-get-selection image)) operation 0 0)
    (gimp-selection-load orig-sel)
    (gimp-image-remove-channel image orig-sel)
    )
  )

(define (sg-by-color-select-along-path image path operation antialias? feather? radius transparent? merged? thresh criterion)
  (let* (
      (drawable (car (gimp-image-get-active-drawable image)))
      (source 0)
      (x1 0)
      (y1 0)
      (x2 (car (gimp-image-width image)))
      (y2 (car (gimp-image-height image)))
      (stroke's (vector->list (cadr (gimp-vectors-get-strokes path))))
      (stroke nil)
      (point nil)
      (x 0)
      (y 0)
      (last-x 0)
      (last-y 0)
      (dist 0)
      (orig-sel 0)
      (color nil)
      )
    (set! orig-sel (car (gimp-selection-save image)))
    (gimp-selection-none image)
    (if (= merged? TRUE)
      (begin
        (set! source (car (gimp-layer-new-from-visible image image "Source")))
        (gimp-image-add-layer image source 0)
        )
      (begin
        (set! source drawable)
        (set! x1 (car (gimp-drawable-offsets source)))
        (set! y1 (cadr (gimp-drawable-offsets source)))
        (set! x2 (+ x1 (car (gimp-drawable-width source))))
        (set! y2 (+ y1 (car (gimp-drawable-height source))))
        )
      )  
    (while (pair? stroke's)
      (set! stroke (car stroke's))
      (set! dist (car (gimp-vectors-stroke-get-length path stroke 0.5)))
      (while (>= dist 0) 
        (set! point (gimp-vectors-stroke-get-point-at-dist path stroke dist 1))
        (set! x (truncate (car point)))
        (set! y (truncate (cadr point)))
        (when (and (or (<> x last-x) (<> y last-y)) (= (cadddr point) 1))
          (when (and (>= x x1) (>= y y1) (< x x2) (< y y2))
            (set! last-x x)
            (set! last-y y)
            (when (and (= merged? FALSE))
              (set! x (- x x1))
              (set! y (- y y1))
              )
            (set! color (vector->list (cadr (gimp-drawable-get-pixel source x y))))
            (if (= (length color) 4)
              (set! color (butlast color))
              )
            (gimp-by-color-select-full source 
                                       color 
                                       thresh 
                                       CHANNEL-OP-ADD 
                                       antialias? 
                                       feather? radius radius
                                       merged? transparent? criterion)
            )
          )
        (set! dist (- dist 1))
        )
      (set! stroke's (cdr stroke's))
      )
    (when (= merged? TRUE)
      (gimp-image-remove-layer source)
      )
    (gimp-channel-combine-masks orig-sel (car (gimp-image-get-selection image)) operation 0 0)
    (gimp-selection-load orig-sel)
    (gimp-image-remove-channel image orig-sel)
    (if (= (car (gimp-drawable-is-layer drawable)) 1)
      (gimp-image-set-active-layer image drawable)
      (if (= (car (gimp-drawable-is-layer-mask drawable)) 1)
        (begin
          (set! drawable (car (gimp-layer-from-mask drawable)))
          (gimp-image-set-active-layer image drawable)
          (gimp-layer-set-edit-mask drawable TRUE)
          )
        (gimp-image-set-active-channel image drawable)
        )
      )
    (gimp-image-set-active-channel image drawable)
    (gimp-image-set-active-layer image drawable)
    )
  )

(define (sg-select-along-path image path tool operation antialias? feather? radius transparent? merged? thresh criterion)
  (gimp-image-undo-group-start image)
  (if (= tool 0)
    (sg-by-color-select-along-path image path operation antialias? feather? radius transparent? merged? thresh criterion)
    (sg-fuzzy-select-along-path    image path operation antialias? feather? radius transparent? merged? thresh criterion)
    )
  (gimp-image-undo-group-end image)
  )
    
(script-fu-register "sg-select-along-path"
         "Select Along Path..."
         "Select along path"
         "Saul Goode"
         "Saul Goode"
         "2009-08-30"
         "*"
         SF-IMAGE    "Image"    0
         SF-VECTORS  "Vectors"  0
         SF-OPTION "Tool" '("Select by color" "Fuzzy select")
         SF-ENUM "Mode" '("ChannelOps" "Replace the current selection")
         SF-TOGGLE "Antialiasing" TRUE
         SF-TOGGLE "Feather edges" FALSE
         SF-ADJUSTMENT "Feather radius" '(10 0 100 1 10 0 1)
         SF-TOGGLE "Select transparent areas" TRUE
         SF-TOGGLE "Sample merged" FALSE
         SF-ADJUSTMENT "Threshold" '(15 0 255 1 10 0 1)
         SF-ENUM "Select by" '("SelectCriterion" "Composite")
         )
(script-fu-menu-register "sg-select-along-path"
                         "<Vectors>")