16 lines
441 B
Racket
16 lines
441 B
Racket
#lang scheme
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(require (prefix-in uni: 2htdp/universe)
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(prefix-in uni: htdp/image))
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(define (create-UFO-scene height)
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(uni:place-image UFO 50 height (uni:empty-scene 100 100)))
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(define UFO
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(uni:overlay (uni:circle 10 'solid 'green)
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(uni:rectangle 40 4 'solid 'green)))
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(uni:big-bang 0
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(uni:on-tick add1)
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(uni:stop-when (lambda (y) (>= y 100)))
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(uni:on-draw create-UFO-scene))
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