46 lines
587 B
Markdown
46 lines
587 B
Markdown
# Prelude
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## Colors
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### Compare two Colors
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Use: `(if (color-eq (255 200 0) (200 255 0)) "yes" "no")`.
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```
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(defn color-eq
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(a b)
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(and
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(eq a:0 b:0)
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(eq a:1 b:1)
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(eq a:2 b:2)))
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```
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## Pixels
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### Erase all pixels of a specific color
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Use: `(pixels erase-color (255 0 0))`.
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```
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(defn erase-color
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(a b)
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(a:0 a:1 a:2
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(if
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(and
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(eq a:0 b:0)
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(eq a:1 b:1)
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(eq a:2 b:2)) 0 255)))
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```
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### Posterize
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Use: `(pixels posterize 40)`.
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```
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(defn posterize
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(a q)
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(
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(step a:0 q)
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(step a:1 q)
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(step a:2 q) a:3))
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``` |