27 lines
543 B
Racket
27 lines
543 B
Racket
#lang planet dyoo/whalesong
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(require (planet dyoo/whalesong/world)
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(planet dyoo/whalesong/image))
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(define width 640)
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(define height 480)
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(define-struct posn (x y))
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(define (mouse world x y type)
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(cond
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[(string=? type "click")
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(make-posn x y)]
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[else
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world]))
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(define (draw w)
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(place-image (circle 20 'solid 'red)
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(posn-x w)
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(posn-y w)
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(empty-scene width height)))
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(big-bang (make-posn 0 0)
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(on-mouse mouse)
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(to-draw draw)) |