Lesson goal: Computer animation with functions and for-loops

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Functions, and their ability to run small chunks of code over and over again, are really useful to animate something more complicated than a single pixel. Why? Because we can use the function to draw a more complicated shape (like a person or car), then just use the function in a for-loop during the repeated drawing and erasing.

Now you try. Try fixing the for and color statements to make a pixel move.

Type your code here:

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1
function draw_person(x,y,c)
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 color(c)
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 width(2)
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 circle(x,y,5)
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 line(x,y-5,x,y-15)
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 line(x,y-15,x-5,y-25)
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 line(x,y-16,x+5,y-25)
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 line(x-10,y-10,x+10,y-10)
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end
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​
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pcls(0)
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for x=0,100,10  do
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  draw_person(x,0,4)
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  pcls(0)
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end

See your results here: