How GameplayKit AI Works
Amongst the many features introduced in GameplayKit, one of the most immediately useful is its ability to provide artificial intelligence that can evaluate a situation and make smart choices. We’re going to be using it in our Four in a Row game to provide a meaningful opponent, but first it’s essential that you understand how GameplayKit tackles the AI problem because it directly affects the code we’ll write.
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GameplayKit’s artificial intelligence works through brute force: it tries every possible move, then tries every possible follow-on move, then every possible follow-on follow-on move, etc. This runs up combinations extremely quickly, particularly when you consider that there are 4,531,985,219,092 unique positions for all the pieces on the board! So, you will inevitably limit the depth of the search to provide just enough intelligence to be interesting.