I have seen systems that use frames/screen captures as input (look up sentdex' GTA series on YouTube for an example) but that isn't what's happening here. In this case, it looks like the `dist` function is directly accessing key game values by reading bytes out of the emulator's memory. So the AI is taking multiple signals from the game's state as input, not just "alive/dead."

The blog post explains that part a bit under the "Distance" section.