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(define WINDOW-WIDTH 150) |
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(define WINDOW-HEIGHT 180) |
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|
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; A world is a number. |
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; Its display is a blue disk of that size. |
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; show-world : world -> image |
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(define (show-world diameter) |
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(circle diameter "solid" "blue")) |
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"Examples of show-world:" |
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(show-world 1) "should be a blue dot" |
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(show-world 20) "should be" (circle 20 "solid" "blue") |
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|
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; The next world is one larger. |
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; next-world : world -> world |
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(define (next-world diameter) |
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(+ 1 diameter)) |
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"Examples of next-world:" |
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(next-world 7) "should be" 8 |
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|
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"Now let's start the animation!" |
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|
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(big-bang WINDOW-WIDTH WINDOW-HEIGHT 1 1) |
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(on-update-event show-world) |
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(on-tick-event next-world) |
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|
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; From https://home.adelphi.edu/sbloch/class/archive/160/spring2005/examples/ |
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