Question

An algorithm for making these things performs a parallel sweep that shrinks a contour while keeping track of contraction events and splitting events; that is the universal molecule algorithm. One of these objects is called uniaxial if it can be directly mapped to its “shadow tree”. Robert J. Lang made the TreeMaker (-5[1])program to help with packing circles and rivers as part of creating these things. A landmark practical algorithm named for making these things was published in 2017 by Tomohiro Tachi and (*) Erik Demaine. (10[1])Small individual units like the Sonobe (“suh-NO-bay”) module are joined to make the “modular” kind of these things. Crease patterns display how to make these (10[1])things, starting from a square (10[2])base and using certain mountain and valley operations. For 10 points, name these Japanese artworks that might be shaped (10[1])like cranes. ■END■

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