842 lines
30 KiB
Scheme
842 lines
30 KiB
Scheme
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The test suite for this code is in
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plt/collects/tests/mzscheme/image-test.ss
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|#
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(module image mzscheme
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(require (lib "mred.ss" "mred")
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(lib "class.ss")
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(lib "cache-image-snip.ss" "mrlib")
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(lib "math.ss")
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(lib "posn.ss" "lang")
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(lib "imageeq.ss" "lang" "private")
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"error.ss")
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(provide image-width
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image-height
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overlay
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overlay/xy
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pinhole-x
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pinhole-y
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move-pinhole
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put-pinhole
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rectangle
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circle
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ellipse
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triangle
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line
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add-line
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text
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shrink
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shrink-tl
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shrink-tr
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shrink-bl
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shrink-br
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image-inside?
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find-image
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image->color-list
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color-list->image
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image->alpha-color-list
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alpha-color-list->image
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image-color?
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make-color
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color-red
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color-green
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color-blue
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color?
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make-alpha-color
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alpha-color-alpha
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alpha-color-red
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alpha-color-green
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alpha-color-blue
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alpha-color?)
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;; ----------------------------------------
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(define (color-list? l)
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(and (list? l) (andmap color? l)))
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(define (alpha-color-list? l)
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(and (list? l) (andmap alpha-color? l)))
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(define-struct color (red green blue) (make-inspector))
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(define-struct alpha-color (alpha red green blue) (make-inspector))
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;; ----------------------------------------
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(define (check name p? v desc arg-posn) (check-arg name (p? v) desc arg-posn v))
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(define (check-coordinate name val arg-posn) (check name number? val "number" arg-posn))
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(define (check-size name val arg-posn) (check name posi? val "positive exact integer" arg-posn))
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(define (check-size/0 name val arg-posn) (check name nnosi? val "non-negative exact integer" arg-posn))
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(define (check-image name val arg-posn) (check name image? val "image" arg-posn))
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(define (check-image-color name val arg-posn) (check name image-color? val "image-color" arg-posn))
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(define (check-mode name val arg-posn) (check name mode? val mode-str arg-posn))
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(define (posi? i) (and (number? i) (integer? i) (positive? i) (exact? i)))
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(define (nnosi? i) (and (number? i) (integer? i) (exact? i) (or (zero? i) (positive? i))))
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(define (check-sizes who w h)
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(unless (and (< 0 w 10000) (< 0 h 10000))
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(error (format "cannot make ~a x ~a image" w h))))
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(define (mode? x)
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(or (eq? x 'solid)
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(eq? x 'outline)))
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(define mode-str "'solid or 'outline")
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(define (mode->brush-symbol m)
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(case m
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[(solid) 'solid]
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[(outline) 'transparent]))
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(define (mode->pen-symbol m)
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(case m
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[(solid) 'transparent]
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[(outline) 'solid]))
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(define (make-color% c)
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(cond
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[(string? c) (send the-color-database find-color c)]
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[(symbol? c) (send the-color-database find-color (symbol->string c))]
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[(color? c) (make-object color%
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(color-red c)
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(color-green c)
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(color-blue c))]
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[else #f]))
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(define (image-color? c)
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(cond
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[(color? c) #t]
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[(string? c) (and (send the-color-database find-color c) #t)]
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[(symbol? c) (and (send the-color-database find-color (symbol->string c)) #t)]
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[else #f]))
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(define (image-width a)
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(check-image 'image-width a "first")
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(let-values ([(w h) (snip-size a)])
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(inexact->exact (ceiling w))))
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(define (image-height a)
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(check-image 'image-height a "first")
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(let-values ([(w h) (snip-size a)])
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(inexact->exact (ceiling h))))
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(define (pinhole-x a)
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(check-image 'pinhole-x a "first")
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(let-values ([(x y) (send (coerce-to-cache-image-snip a) get-pinhole)])
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x))
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(define (pinhole-y a)
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(check-image 'pinhole-y a "first")
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(let-values ([(x y) (send (coerce-to-cache-image-snip a) get-pinhole)])
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y))
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(define (move-pinhole raw-i dx dy)
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(check-image 'move-pinhole raw-i "first")
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(check-coordinate 'move-pinhole dx "second")
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(check-coordinate 'move-pinhole dy "third")
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(let ([i (coerce-to-cache-image-snip raw-i)])
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(let-values ([(px py) (send i get-pinhole)]
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[(w h) (send i get-size)])
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(new cache-image-snip%
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(dc-proc (send i get-dc-proc))
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(argb-proc (send i get-argb-proc))
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(width w)
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(height h)
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(argb (send i get-argb/no-compute))
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(px (+ px dx))
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(py (+ py dy))))))
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(define (put-pinhole raw-i px py)
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(check-image 'put-pinhole raw-i "first")
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(check-coordinate 'put-pinhole px "second")
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(check-coordinate 'put-pinhole py "third")
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(let ([i (coerce-to-cache-image-snip raw-i)])
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(let-values ([(w h) (send i get-size)])
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(new cache-image-snip%
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(dc-proc (send i get-dc-proc))
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(argb-proc (send i get-argb-proc))
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(width w)
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(height h)
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(argb (send i get-argb/no-compute))
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(px (floor px))
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(py (floor py))))))
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(define (overlay a b . cs)
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(check-image 'overlay a "first")
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(check-image 'overlay b "second")
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(let loop ([cs cs]
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[i 3])
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(unless (null? cs)
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(check-image 'overlay (car cs) (number->ord i))))
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(let ([all-imgs (reverse (list* a b cs))])
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(let loop ([imgs (cdr all-imgs)]
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[acc (car all-imgs)])
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(cond
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[(null? imgs) acc]
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[else (loop (cdr imgs)
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(real-overlay/xy 'overlay (car imgs) 0 0 acc))]))))
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(define (overlay/xy a dx dy b)
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(check-image 'overlay/xy a "first")
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(check-coordinate 'overlay/xy dx "second")
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(check-coordinate 'overlay/xy dy "third")
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(check-image 'overlay/xy b "fourth")
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(real-overlay/xy 'overlay/xy a dx dy b))
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(define (real-overlay/xy name raw-a raw-delta-x raw-delta-y raw-b)
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(let ([a (coerce-to-cache-image-snip raw-a)]
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[b (coerce-to-cache-image-snip raw-b)])
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(let-values ([(a-w a-h) (snip-size a)]
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[(b-w b-h) (snip-size b)]
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[(a-px a-py) (send a get-pinhole)]
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[(b-px b-py) (send b get-pinhole)])
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(let* ([delta-x (+ raw-delta-x a-px (- b-px))]
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[delta-y (+ raw-delta-y a-py (- b-py))]
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[left (min 0 delta-x)]
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[top (min 0 delta-y)]
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[right (max (+ delta-x b-w) a-w)]
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[bottom (max (+ delta-y b-h) a-h)]
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[new-w (ceiling (- right left))]
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[new-h (ceiling (- bottom top))]
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[a-dx (- left)]
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[a-dy (- top)]
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[b-dx (- delta-x left)]
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[b-dy (- delta-y top)]
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[new-px (- a-px left)]
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[new-py (- a-py top)]
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[combine (lambda (a-f b-f)
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(lambda (dc dx dy)
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(a-f dc (+ dx a-dx) (+ dy a-dy))
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(b-f dc (+ dx b-dx) (+ dy b-dy))))])
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(check-sizes name new-w new-h)
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(new cache-image-snip%
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[dc-proc (combine (send a get-dc-proc)
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(send b get-dc-proc))]
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[argb-proc (combine (send a get-argb-proc)
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(send b get-argb-proc))]
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[width new-w]
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[height new-h]
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[px new-px]
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[py new-py])))))
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;; ------------------------------------------------------------
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(define (shrink raw-img left up right down)
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(check-image 'shrink raw-img "first")
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(check-size/0 'shrink left "second")
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(check-size/0 'shrink up "third")
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(check-size/0 'shrink right "fourth")
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(check-coordinate 'shrink down "fifth")
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(let ([img (coerce-to-cache-image-snip raw-img)])
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(let-values ([(i-px i-py) (send img get-pinhole)]
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[(i-width i-height) (send img get-size)])
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(let* ([dc-proc (send img get-dc-proc)]
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[argb-proc (send img get-argb-proc)]
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[delta-w (- i-px left)]
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[delta-h (- i-py up)]
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[width (+ left right 1)]
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[height (+ up down 1)])
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(new cache-image-snip%
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[px left]
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[py up]
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[dc-proc (lambda (dc dx dy)
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(let ([clip (send dc get-clipping-region)])
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(send dc set-clipping-rect dx dy width height)
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(dc-proc dc (- dx delta-w) (- dy delta-h))
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(send dc set-clipping-region clip)))]
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[argb-proc (lambda (argb dx dy) (argb-proc argb (- dx delta-w) (- dy delta-h)))]
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[width width]
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[height height])))))
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(define (shrink-tl raw-img x y)
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(check-image 'shrink-tl raw-img "first")
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(check-size 'shrink-tl x "second")
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(check-size 'shrink-tl y "third")
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(put-pinhole (shrink (put-pinhole raw-img 0 0) 0 0 (- x 1) (- y 1)) (/ x 2) (/ y 2)))
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(define (shrink-tr raw-img x y)
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(check-image 'shrink-tr raw-img "first")
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(check-size 'shrink-tr x "second")
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(check-size 'shrink-tr y "third")
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(put-pinhole (shrink (put-pinhole raw-img (- (image-width raw-img) 1) 0) (- x 1) 0 0 (- y 1))
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(/ x 2)
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(/ y 2)))
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(define (shrink-bl raw-img x y)
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(check-image 'shrink-bl raw-img "first")
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(check-size 'shrink-bl x "second")
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(check-size 'shrink-bl y "third")
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(put-pinhole (shrink (put-pinhole raw-img 0 (- (image-height raw-img) 1)) 0 (- y 1) (- x 1) 0)
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(/ x 2)
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(/ y 2)))
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(define (shrink-br raw-img x y)
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(check-image 'shrink-br raw-img "first")
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(check-size 'shrink-br x "second")
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(check-size 'shrink-br y "third")
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(put-pinhole (shrink (put-pinhole raw-img (- (image-width raw-img) 1) (- (image-height raw-img) 1))
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(- x 1)
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(- y 1)
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0
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0)
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(/ x 2)
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(/ y 2)))
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;; ------------------------------------------------------------
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(define (line x y color)
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(check-coordinate 'line x "first")
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(check-coordinate 'line y "second")
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(check-image-color 'line color "third")
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(check-sizes 'line (+ x 1) (+ y 1))
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(let ([draw-proc
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(make-color-wrapper
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color 'transparent 'solid
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(lambda (dc dx dy)
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(send dc draw-line dx dy (+ dx x) (+ dy y))))]
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[mask-proc
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(make-color-wrapper
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'black 'transparent 'solid
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(lambda (dc dx dy)
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(send dc draw-line dx dy (+ dx x) (+ dy y))))])
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(make-simple-cache-image-snip (+ x 1) (+ y 1) 0 0 draw-proc mask-proc)))
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;; test what happens when the line moves out of the box.
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(define (add-line raw-i pre-x1 pre-y1 pre-x2 pre-y2 color-in)
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(check-image 'add-line raw-i "first")
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(check-coordinate 'add-line pre-x1 "second")
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(check-coordinate 'add-line pre-y1 "third")
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(check-coordinate 'add-line pre-x2 "fourth")
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(check-coordinate 'add-line pre-y2 "fifth")
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(check-image-color 'add-line color-in "sixth")
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(let ([i (coerce-to-cache-image-snip raw-i)])
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(let-values ([(px py) (send i get-pinhole)]
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[(iw ih) (send i get-size)]
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[(x1 y1 x2 y2)
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(if (<= pre-x1 pre-x2)
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(values pre-x1 pre-y1 pre-x2 pre-y2)
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(values pre-x2 pre-y2 pre-x1 pre-y1))])
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(let* ([line-w (+ (abs (- x2 x1)) 1)]
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[line-h (+ (abs (- y2 y1)) 1)])
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(if (y1 . <= . y2)
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(let* ([do-draw
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(lambda (dc dx dy)
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(send dc draw-line
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dx
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dy
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(+ dx (- x2 x1))
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(+ dy (- y2 y1))))]
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[draw-proc
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(make-color-wrapper color-in 'transparent 'solid do-draw)]
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[mask-proc
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(make-color-wrapper 'black 'transparent 'solid do-draw)]
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[line
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(make-simple-cache-image-snip line-w line-h px py draw-proc mask-proc)])
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(real-overlay/xy 'add-line i (+ px x1) (+ py y1) line))
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(let* ([do-draw
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(lambda (dc dx dy)
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(send dc draw-line
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dx
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(+ dy (- line-h 1))
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(+ dx (- line-w 1))
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dy))]
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[draw-proc
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(make-color-wrapper color-in 'transparent 'solid do-draw)]
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[mask-proc
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(make-color-wrapper 'black 'transparent 'solid do-draw)]
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[line
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(make-simple-cache-image-snip line-w line-h px py draw-proc mask-proc)])
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(real-overlay/xy 'add-line i (+ px x1) (+ py y2) line)))))))
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(define (text str size color-in)
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(check 'text string? str "string" "first")
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(check 'text (lambda (x) (and (integer? x) (<= 1 x 255))) size "integer between 1 and 255" "second")
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(check-image-color 'text color-in "third")
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(let ([color (make-color% color-in)])
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(let-values ([(tw th) (get-text-size size str)])
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(let ([draw-proc
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(lambda (txt-color mode dc dx dy)
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(let ([old-mode (send dc get-text-mode)]
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[old-fore (send dc get-text-foreground)]
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[old-font (send dc get-font)])
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(send dc set-text-mode mode)
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(send dc set-text-foreground txt-color)
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(send dc set-font (get-font size))
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(send dc draw-text str dx dy)
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(send dc set-text-mode old-mode)
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(send dc set-text-foreground old-fore)
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(send dc set-font old-font)))])
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(new cache-image-snip%
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[dc-proc (lambda (dc dx dy) (draw-proc color 'transparent dc dx dy))]
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[argb-proc
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(lambda (argb dx dy)
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(let ([bm-color
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(build-bitmap
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(lambda (dc)
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(send dc set-pen (send the-pen-list find-or-create-pen "black" 1 'transparent))
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(send dc set-brush (send the-brush-list find-or-create-brush color 'solid))
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(send dc draw-rectangle 0 0 tw th))
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tw
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th)]
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[bm-mask
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(build-bitmap
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(lambda (dc)
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(draw-proc
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(send the-color-database find-color "black")
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'solid dc 0 0))
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tw
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th)])
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(overlay-bitmap argb dx dy bm-color bm-mask)))]
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[width tw]
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[height th]
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[px 0]
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[py 0])))))
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(define (get-text-size size string)
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(let* ([bm (make-object bitmap% 1 1)]
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[dc (make-object bitmap-dc% bm)])
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(let-values ([(w h _1 _2) (send dc get-text-extent string (get-font size))])
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(values (inexact->exact (ceiling w))
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(inexact->exact (ceiling h))))))
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(define (get-font size)
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(send the-font-list find-or-create-font size
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'default 'normal 'normal #f
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(case (system-type)
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[(macosx) 'partly-smoothed]
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[else 'smoothed])))
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(define (a-rect/circ who do-draw w h color brush pen)
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(check-sizes who w h)
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(let* ([dc-proc (make-color-wrapper color brush pen do-draw)]
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[mask-proc (make-color-wrapper 'black brush pen do-draw)])
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(make-simple-cache-image-snip w h (floor (/ w 2)) (floor (/ h 2)) dc-proc mask-proc)))
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(define (rectangle w h mode color)
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(check-size 'rectangle w "first")
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(check-size 'rectangle h "second")
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(check-mode 'rectangle mode "third")
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(check-image-color 'rectangle color "fourth")
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(a-rect/circ 'rectangle
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(lambda (dc dx dy) (send dc draw-rectangle dx dy w h))
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w h color (mode->brush-symbol mode) (mode->pen-symbol mode)))
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(define (ellipse w h mode color)
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(check-size 'ellipse w "first")
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(check-size 'ellipse h "second")
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(check-mode 'ellipse mode "third")
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(check-image-color 'ellipse color "fourth")
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(a-rect/circ 'ellipse
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(lambda (dc dx dy) (send dc draw-ellipse dx dy w h))
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w h color (mode->brush-symbol mode) (mode->pen-symbol mode)))
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(define (circle r mode color)
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(check-size 'circle r "first")
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(check-mode 'circle mode "second")
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(check-image-color 'circle color "third")
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(a-rect/circ 'circle
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(lambda (dc dx dy) (send dc draw-ellipse dx dy (* 2 r) (* 2 r)))
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(* 2 r) (* 2 r) color (mode->brush-symbol mode) (mode->pen-symbol mode)))
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(define (triangle size mode color)
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(check 'triangle
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(lambda (x) (and (real? x) (< 2 x 10000)))
|
|
size
|
|
"positive real number bigger than 2"
|
|
"first")
|
|
(check-mode 'triangle mode "second")
|
|
(check-image-color 'triangle color "third")
|
|
(let* ([right (- size 1)]
|
|
[bottom (inexact->exact (ceiling (* size (sin (* 2/3 pi)))))]
|
|
[points (list (make-object point% 0 bottom)
|
|
(make-object point% right bottom)
|
|
(make-object point% (/ size 2) 0))])
|
|
(let ([draw (make-color-wrapper
|
|
color (mode->brush-symbol mode) 'solid
|
|
(lambda (dc dx dy)
|
|
(send dc draw-polygon points dx dy)))]
|
|
[mask-draw (make-color-wrapper
|
|
'black (mode->brush-symbol mode) 'solid
|
|
(lambda (dc dx dy)
|
|
(send dc draw-polygon points dx dy)))]
|
|
[w size]
|
|
[h (+ bottom 1)])
|
|
(make-simple-cache-image-snip w h (floor (/ w 2)) (floor (/ h 2)) draw mask-draw))))
|
|
|
|
(define (make-simple-cache-image-snip w h px py dc-proc mask-proc)
|
|
(let ([argb-proc
|
|
(lambda (argb-vector dx dy)
|
|
(let ([c-bm (build-bitmap (lambda (dc) (dc-proc dc 0 0)) w h)]
|
|
[m-bm (build-bitmap (lambda (dc) (mask-proc dc 0 0)) w h)])
|
|
(overlay-bitmap argb-vector dx dy c-bm m-bm)))])
|
|
(new cache-image-snip%
|
|
[dc-proc dc-proc]
|
|
[argb-proc argb-proc]
|
|
[width w]
|
|
[height h]
|
|
[px px]
|
|
[py py])))
|
|
|
|
(define (make-color-wrapper color-in brush pen rest)
|
|
(let ([color (make-color% color-in)])
|
|
(lambda (dc dx dy)
|
|
(let ([old-brush (send dc get-brush)]
|
|
[old-pen (send dc get-pen)])
|
|
(send dc set-brush (send the-brush-list find-or-create-brush color brush))
|
|
(send dc set-pen (send the-pen-list find-or-create-pen color 1 pen))
|
|
(rest dc dx dy)
|
|
(send dc set-pen old-pen)
|
|
(send dc set-brush old-brush)))))
|
|
|
|
;; ------------------------------------------------------------
|
|
|
|
(define (image-inside? i a)
|
|
(and (locate-image 'image-inside?
|
|
(coerce-to-cache-image-snip i)
|
|
(coerce-to-cache-image-snip a))
|
|
#t))
|
|
|
|
(define (find-image i a)
|
|
(or (locate-image 'find-image
|
|
(coerce-to-cache-image-snip i)
|
|
(coerce-to-cache-image-snip a))
|
|
(error 'find-image
|
|
"the second image does not appear within the first image")))
|
|
|
|
(define (locate-image who i a)
|
|
(check-image who i "first")
|
|
(check-image who a "second")
|
|
(let-values ([(iw ih) (snip-size i)]
|
|
[(ipx ipy) (send i get-pinhole)]
|
|
[(aw ah) (snip-size a)]
|
|
[(apx apy) (send a get-pinhole)])
|
|
(and (iw . >= . aw)
|
|
(ih . >= . ah)
|
|
(let ([i-argb-vector (argb-vector (send i get-argb))]
|
|
[a-argb-vector (argb-vector (send a get-argb))])
|
|
(let ([al (let loop ([offset 0])
|
|
(cond
|
|
[(= offset (* ah aw 4)) null]
|
|
[else (cons (subvector a-argb-vector offset (+ offset (* 4 aw)))
|
|
(loop (+ offset (* 4 aw))))]))])
|
|
(let yloop ([dy 0])
|
|
(and (dy . <= . (- ih ah))
|
|
(let xloop ([dx 0])
|
|
(if (dx . <= . (- iw aw))
|
|
(if (let loop ([al al][dd 0])
|
|
(or (null? al)
|
|
(and (first-in-second?
|
|
i-argb-vector
|
|
(car al)
|
|
(* 4 (+ (* (+ dy dd) iw) dx)))
|
|
(loop (cdr al) (add1 dd)))))
|
|
(make-posn (+ dx (- apx ipx)) (+ dy (- apy ipy)))
|
|
(xloop (add1 dx)))
|
|
(yloop (add1 dy)))))))))))
|
|
|
|
(define (subvector orig i j)
|
|
(let ([v (make-vector (- j i) #f)])
|
|
(let loop ([x i])
|
|
(when (< x j)
|
|
(vector-set! v (- x i) (vector-ref orig x))
|
|
(loop (+ x 1))))
|
|
v))
|
|
#|
|
|
(initial inequalities thanks to Matthew (thanks!!))
|
|
|
|
We know that, for a combination:
|
|
m3 = (m1+m2-m1*m2) and
|
|
b3 = (m1*b1*(1-m2) + m2*b2)/m3
|
|
|
|
So, we need to figure out what m1 & m2 might have been,
|
|
given the other values.
|
|
|
|
Check m3:
|
|
|
|
m3 = m2 when m1 = 0
|
|
m3 = 1 when m1 = 1
|
|
|
|
[deriv of m3 with respect to m1 = 1 - m2, which is positive]
|
|
|
|
so check that m3 is between m2 and 1
|
|
|
|
Then check m3*b3:
|
|
|
|
b3*m3 = m2*b2 when m1 = 0 or b1 = 0
|
|
b3*m3 = (1 - m2) + m2*b2 when m1 = b1 = 1
|
|
|
|
[deriv with respect to m1 is b1*(1-m2), which is positive]
|
|
[deriv with respect to b1 is m1*(1-m2), which is positive]
|
|
|
|
So check that m3*b3 is between m2*b2 and (1 - m2) + m2*b2
|
|
|
|
This is all in alphas from 0 to 1 and needs to be from 255 to 0.
|
|
Converting (but using the same names) for the alpha test, we get:
|
|
|
|
(<= (- 1 (/ m2 255))
|
|
(- 1 (/ m3 255))
|
|
1)
|
|
|
|
sub1 to each:
|
|
|
|
(<= (- (/ m2 255))
|
|
(- (/ m3 255))
|
|
0)
|
|
|
|
mult by 255:
|
|
|
|
(<= (- m2)
|
|
(- m3)
|
|
0)
|
|
|
|
negate and flip ineq:
|
|
|
|
|
|
(>= m2 m3 0)
|
|
|
|
flip ineq back:
|
|
|
|
(<= 0 m3 m2)
|
|
|
|
|
|
Here's the original scheme expression for the second check:
|
|
|
|
(<= (* m2 b2)
|
|
(* m3 b3)
|
|
(+ (- 1 m2) (* m2 b2))
|
|
|
|
converting from the computer's coordinates, we get:
|
|
|
|
|
|
(<= (* (- 1 (/ m2 255)) (- 1 (/ b2 255)))
|
|
(* (- 1 (/ m3 255)) (- 1 (/ b3 255)))
|
|
(+ (- 1 (- 1 (/ m2 255)))
|
|
(* (- 1 (/ m2 255)) (- 1 (/ b2 255)))))
|
|
|
|
;; multiplying out the binomials:
|
|
|
|
(<= (+ 1
|
|
(- (/ m2 255))
|
|
(- (/ b2 255))
|
|
(/ (* m2 b2) (* 255 255)))
|
|
(+ 1
|
|
(- (/ m3 255))
|
|
(- (/ b3 255))
|
|
(/ (* m3 b3) (* 255 255)))
|
|
(+ (- 1 (- 1 (/ m2 255)))
|
|
(+ 1
|
|
(- (/ m2 255))
|
|
(- (/ b2 255))
|
|
(/ (* m2 b2) (* 255 255)))))
|
|
|
|
;; simplifying the last term
|
|
|
|
(<= (+ 1
|
|
(- (/ m2 255))
|
|
(- (/ b2 255))
|
|
(/ (* m2 b2) (* 255 255)))
|
|
(+ 1
|
|
(- (/ m3 255))
|
|
(- (/ b3 255))
|
|
(/ (* m3 b3) (* 255 255)))
|
|
(+ 1
|
|
(- (/ b2 255))
|
|
(/ (* m2 b2) (* 255 255))))
|
|
|
|
;; multiply thru by 255:
|
|
|
|
(<= (+ 255
|
|
(- m2)
|
|
(- b2)
|
|
(* m2 b2 1/255))
|
|
(+ 255
|
|
(- m3)
|
|
(- b3)
|
|
(* m3 b3 1/255))
|
|
(+ 255
|
|
(- b2)
|
|
(* m2 b2 1/255)))
|
|
|
|
;; subtract out 255 from each:
|
|
|
|
(<= (+ (- m2)
|
|
(- b2)
|
|
(* m2 b2 1/255))
|
|
(+ (- m3)
|
|
(- b3)
|
|
(* m3 b3 1/255))
|
|
(+ (- b2)
|
|
(* m2 b2 1/255)))
|
|
|
|
;; negate them all, and reverse the inequality
|
|
|
|
(>= (+ m2 b2 (* m2 b2 -1/255))
|
|
(+ m3 b3 (* m3 b3 -1/255))
|
|
(+ b2 (* m2 b2 -1/255)))
|
|
|
|
;; aka
|
|
|
|
(<= (+ b2 (* m2 b2 -1/255))
|
|
(+ m3 b3 (* m3 b3 -1/255))
|
|
(+ m2 b2 (* m2 b2 -1/255)))
|
|
|
|
|#
|
|
|
|
;; in the above, m3 & b3 come from iv
|
|
;; and m2 & b2 come from av
|
|
(define (first-in-second? iv av xd)
|
|
(let loop ([i (vector-length av)])
|
|
(or (zero? i)
|
|
(let ([a (- i 4)]
|
|
[r (- i 3)]
|
|
[g (- i 2)]
|
|
[b (- i 1)])
|
|
(let* ([m2 (vector-ref av a)]
|
|
[m3 (vector-ref iv (+ xd a))]
|
|
[test
|
|
(lambda (b2 b3)
|
|
(<= (+ b2 (* m2 b2 -1/255))
|
|
(+ m3 b3 (* m3 b3 -1/255))
|
|
(+ m2 b2 (* m2 b2 -1/255))))])
|
|
(and (<= 0 m3 m2)
|
|
(test (vector-ref av r) (vector-ref iv (+ xd r)))
|
|
(test (vector-ref av g) (vector-ref iv (+ xd g)))
|
|
(test (vector-ref av b) (vector-ref iv (+ xd b)))
|
|
(loop (- i 4))))))))
|
|
|
|
;; ----------------------------------------
|
|
|
|
(define (image->color-list i-raw)
|
|
(check-image 'image->color-list i-raw "first")
|
|
(let* ([cis (coerce-to-cache-image-snip i-raw)]
|
|
[i (send cis get-bitmap)]
|
|
[iw (send i get-width)]
|
|
[ih (send i get-height)]
|
|
[new-bitmap (make-object bitmap% iw ih)]
|
|
[bdc (make-object bitmap-dc% new-bitmap)])
|
|
(send bdc clear)
|
|
(send bdc draw-bitmap i 0 0 'solid
|
|
(send the-color-database find-color "black")
|
|
(send i get-loaded-mask))
|
|
(let ([is (make-bytes (* 4 iw ih))]
|
|
[cols (make-vector (* iw ih))])
|
|
(send bdc get-argb-pixels 0 0 iw ih is)
|
|
(let yloop ([y 0][pos 0])
|
|
(unless (= y ih)
|
|
(let xloop ([x 0][pos pos])
|
|
(if (= x iw)
|
|
(yloop (add1 y) pos)
|
|
(begin
|
|
(vector-set! cols (+ x (* y iw))
|
|
(make-color (bytes-ref is (+ 1 pos))
|
|
(bytes-ref is (+ 2 pos))
|
|
(bytes-ref is (+ 3 pos))))
|
|
(xloop (add1 x) (+ pos 4)))))))
|
|
(send bdc set-bitmap #f)
|
|
(vector->list cols))))
|
|
|
|
(define (image->alpha-color-list i)
|
|
(check-image 'image->alpha-color-list i "first")
|
|
(let* ([argb (cond
|
|
[(is-a? i image-snip%)
|
|
(send (coerce-to-cache-image-snip i) get-argb)]
|
|
[(is-a? i cache-image-snip%) (send i get-argb)])]
|
|
[v (argb-vector argb)])
|
|
(let loop ([i (vector-length v)]
|
|
[a null])
|
|
(cond
|
|
[(zero? i) a]
|
|
[else (loop (- i 4)
|
|
(cons (make-alpha-color
|
|
(vector-ref v (- i 4))
|
|
(vector-ref v (- i 3))
|
|
(vector-ref v (- i 2))
|
|
(vector-ref v (- i 1)))
|
|
a))]))))
|
|
|
|
(define (color-list->image cl w h px py)
|
|
(check 'color-list->image color-list? cl "list-of-colors" "first")
|
|
(check-size 'color-list->image w "second")
|
|
(check-size 'color-list->image h "third")
|
|
(check-coordinate 'color-list->image px "fourth")
|
|
(check-coordinate 'color-list->image py "fifth")
|
|
(unless (and (< 0 w 10000) (< 0 h 10000))
|
|
(error (format "cannot make ~a x ~a image" w h)))
|
|
(unless (= (* w h) (length cl))
|
|
(error (format "given width times given height is ~a, but the given color list has ~a items"
|
|
(* w h) (length cl))))
|
|
(let* ([bm (make-object bitmap% w h)]
|
|
[mask-bm (make-object bitmap% w h)]
|
|
[dc (make-object bitmap-dc% bm)]
|
|
[mask-dc (make-object bitmap-dc% mask-bm)])
|
|
(unless (send bm ok?)
|
|
(error (format "cannot make ~a x ~a image" w h)))
|
|
(let ([is (make-bytes (* 4 w h) 0)]
|
|
[mask-is (make-bytes (* 4 w h) 0)]
|
|
[cols (list->vector cl)])
|
|
(let yloop ([y 0][pos 0])
|
|
(unless (= y h)
|
|
(let xloop ([x 0][pos pos])
|
|
(if (= x w)
|
|
(yloop (add1 y) pos)
|
|
(let* ([col (vector-ref cols (+ x (* y w)))]
|
|
[r (pk color-red col)]
|
|
[g (pk color-green col)]
|
|
[b (pk color-blue col)])
|
|
(bytes-set! is (+ 1 pos) r)
|
|
(bytes-set! is (+ 2 pos) g)
|
|
(bytes-set! is (+ 3 pos) b)
|
|
(when (= 255 r g b)
|
|
(bytes-set! mask-is (+ 1 pos) 255)
|
|
(bytes-set! mask-is (+ 2 pos) 255)
|
|
(bytes-set! mask-is (+ 3 pos) 255))
|
|
(xloop (add1 x) (+ pos 4)))))))
|
|
(send dc set-argb-pixels 0 0 w h is)
|
|
(send mask-dc set-argb-pixels 0 0 w h mask-is))
|
|
(send dc set-bitmap #f)
|
|
(send mask-dc set-bitmap #f)
|
|
(bitmaps->cache-image-snip bm mask-bm px py)))
|
|
|
|
(define (pk sel col) (min 255 (max 0 (sel col))))
|
|
|
|
(define (alpha-color-list->image cl w h px py)
|
|
(check 'alpha-color-list->image alpha-color-list? cl "list-of-alpha-colors" "first")
|
|
(check-size 'alpha-color-list->image w "second")
|
|
(check-size 'alpha-color-list->image h "third")
|
|
(check-coordinate 'alpha-color-list->image px "fourth")
|
|
(check-coordinate 'alpha-color-list->image py "fifth")
|
|
(unless (and (< 0 w 10000) (< 0 h 10000))
|
|
(error (format "cannot make ~a x ~a image" w h)))
|
|
(unless (= (* w h) (length cl))
|
|
(error (format "given width times given height is ~a, but the given color list has ~a items"
|
|
(* w h) (length cl))))
|
|
(let ([index-list (alpha-colors->ent-list cl)])
|
|
(argb->cache-image-snip (make-argb (list->vector index-list) w) px py)))
|
|
|
|
;; alpha-colors->ent-list : (listof alpha-color) -> (listof number)
|
|
(define (alpha-colors->ent-list cl)
|
|
(let loop ([cl cl])
|
|
(cond
|
|
[(null? cl) null]
|
|
[else
|
|
(let ([ac (car cl)])
|
|
(list* (alpha-color-alpha ac)
|
|
(alpha-color-red ac)
|
|
(alpha-color-green ac)
|
|
(alpha-color-blue ac)
|
|
(loop (cdr cl))))]))))
|