Hinged Tessellations

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Some tessellations you can open out and close up.
Contributed by: Borut Levart (January 2013)
Open content licensed under CC BY-NC-SA
Snapshots
Details
Open the tessellation, extend its region, zoom in or out, drag to pan the image, or select a different tessellation.
Such tessellations are composed of solid pieces hinged at their vertices and separated by empty space. At some intermediate positions, the white spaces assume regular shapes.
Snapshot 1: tessellation of equilateral triangles of two sizes
Snapshot 2: tessellation of squares and rhombuses
Snapshot 3: tessellation of crosses and 12-gons
Reference
[1] D. Wells, The Penguin Dictionary of Curious and Interesting Geometry, New York: Penguin, 1991.
Permanent Citation
"Hinged Tessellations"
http://demonstrations.wolfram.com/HingedTessellations/
Wolfram Demonstrations Project
Published: January 3 2013