I get why slide to unlock is wishy-washy, but I don't understand why you use the example of Pi. There may be only 1 way to generate Pi, but there are numerous ways of approximating it. Likewise, there are many ways to compress a file into a smaller one. If what matters is a procedure from going from A to B (e.g. taking a physical input from a human and turning it into electrical signals for directional input), and a compression algorithm takes you from A to B in a new way, the compression algorithm should be a patentsince it's a novel process, and the proofs and implementations of said patent would be copyrightable, no?