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 program to help with packing circles and rivers as part of creating these things. A landmark practical algorithm (-5[1])named for making these things was published in 2017 by Tomohiro Tachi and (*) Erik Demaine. Small individual units (10[1])like the Sonobe (“suh-NO-bay”) module are joined to make the (10[1])“modular” (10[1])kind of these things. Crease patterns display how to make these things, starting from a square base and using certain mountain and valley operations. For 10 points, name these Japanese artworks that might be shaped like cranes. ■END■ (10[1])

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