Here are two separate programs. The first does most of the work - it translates an image into 3 lists of coordinates. The second simply looks at those lists and uses lines to create the original image. Although these probably won't be ever used because of how slow they are and the enormous lists they create, it was fun to program these, regardless. I'm throwing them in here just in case someone wants to fiddle around with them.
Compatible with: TI-83+
(Let me know if it works with more calculators.)
Variables used: A, S, X, Y, ⸤X1, ⸤X2, ⸤Y
If you're curious about how this works…