Learning Processing: A Beginner's Guide to Programming Images ...

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Exercise 17-10: Create a sketch that starts with characters randomly scattered (and rotated).
Have them slowly move back toward their “ home ” location. Use an object-oriented approach
as seen in Example 17-6. 1
One way to solve this is to use interpolation. Interpolation refers to the process of
calculating values in between two given pieces of data. In this exercise, we want to know
the in-between x locations (and y locations) from the random starting point to the target
location in the String . One interpolation method is to simply take the average. Th ink of it
as walking to a wall by always taking a step halfway.
x = (x + targetX) /2;
y = (y + targetY) /2;
Another possibility is to simply go 10% of the way there.
x = 0.9*x + 0.l*targetX;
y = 0.9*y + 0.l*targetY;
Processing ’s lerp( ) function will do interpolation for you. Visit the reference page for more
information: http://processing.org/reference/lerp_.html.
Consider making your sketch interactive. Can you push the letters around using the mouse?
1 Th e origins of this exercise can be traced back to John Maeda’s 1995 work: Flying Letters .