WaveFunctionCollapse is Constraint Solving in the Wild

https://adamsmith.as/papers/wfc_is_constraint_solving_in_the_wild.pdf

Public release 2016-09-30; WFC as MRV-ordered search with arc-consistency propagation and global restarts; Caves of Qud and Proc Skater 2016 as early users; global constraints caused many conflicts that backtracking resolved.

Wave Function Collapse and constraint-based tile generation