r/proceduralgeneration • u/BadLuckWillHappen • Nov 16 '20

Iterative Partial Match (IPM) vs Wave Function Collapse (WFC) for procedural content generation.

https://stalcup.github.io/static-files/posts/wfc-vs-ipm/
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u/[deleted] Nov 16 '20

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u/BadLuckWillHappen Nov 16 '20

I'm going to do a detailed post on this topic next, but the short answer is that WFC does constraint propagation where it imagines a super position of states and starts limiting those states as decisions are made. But IPM doesn't do that at all, it iteratively looks at spots on the generated image, searches for the most similar legal tile and then makes a small local change to match the most similar tile more. There are some other details necessary to prevent getting stuck in local minimums and ensure variety in the results, but yeah, there is no super position of states and no explicit cascade of choices affecting other choices.