This example draws a circle as the cursor’s position but keeps the circle within a rectangle. It does so by passing the mouse’s coordinates into the constrain() function.
Constrain by p5.js Contributors and the Processing Foundation is licensed under CC BY-NC-SA 4.0.
Related Examples
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A small white circle on a grey background.
Linear Interpolation
Convert a number between 0 and 1 to another range.
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A large yellow circle on a black background.
Map
Convert a number from one range to another range.
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A small purple circle on a black background.
Random
Get random numbers.
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A small white circle in a pink rectangle.
Constrain
Keep a number within a range.
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A pink clock on a grey background.
Clock
Get the current time.