30 lines
688 B
Plaintext
30 lines
688 B
Plaintext
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;;; Rubber banding
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;;; (stroke out a box with mousebutton 1)
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(define x1 0)
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(define y1 0)
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(define (item-delete c)
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(c 'delete 'area))
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(define (item-mark c x y)
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(set! x1 (c 'canvasx x))
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(set! y1 (c 'canvasy y))
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(item-delete c))
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(define (item-stroke c x y)
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(set! x (c 'canvasx x))
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(set! y (c 'canvasy y))
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(unless (and (= x1 x) (= y1 y))
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(item-delete c)
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(c 'addtag 'area 'withtag (c 'create 'rectangle x1 y1 x y))))
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(pack (canvas '.c1) :fill "both" :expand #t)
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(bind .c1 "<ButtonPress-1>" (lambda (x y) (item-mark .c1 x y)))
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(bind .c1 "<B1-Motion>" (lambda (x y) (item-stroke .c1 x y)))
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(bind .c1 "<ButtonRelease-1>" (lambda () (item-delete .c1)))
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