# Square tiling

Square tiling TypeRegular tiling
Vertex configuration4.4.4.4 (or 44) Schläfli symbol(s){4,4}
{}×{}
Wythoff symbol(s)4 | 2 4
Coxeter diagram(s)                                    Symmetryp4m, [4,4], (*442)
Rotation symmetryp4, [4,4]+, (442)
Dualself-dual
PropertiesVertex-transitive, edge-transitive, face-transitive

In geometry, the square tiling, square tessellation or square grid is a regular tiling of the Euclidean plane. It has Schläfli symbol of {4,4}, meaning it has 4 squares around every vertex.

The internal angle of the square is 90 degrees so four squares at a point make a full 360 degrees. It is one of three regular tilings of the plane. The other two are the triangular tiling and the hexagonal tiling.

## Uniform colorings

There are 9 distinct uniform colorings of a square tiling. Naming the colors by indices on the 4 squares around a vertex: 1111, 1112(i), 1112(ii), 1122, 1123(i), 1123(ii), 1212, 1213, 1234. (i) cases have simple reflection symmetry, and (ii) glide reflection symmetry. Three can be seen in the same symmetry domain as reduced colorings: 1112i from 1213, 1123i from 1234, and 1112ii reduced from 1123ii.

This tiling is topologically related as a part of sequence of regular polyhedra and tilings, extending into the hyperbolic plane: {4,p}, p=3,4,5...

This tiling is also topologically related as a part of sequence of regular polyhedra and tilings with four faces per vertex, starting with the octahedron, with Schläfli symbol {n,4}, and Coxeter diagram     , with n progressing to infinity.

## Wythoff constructions from square tiling

Like the uniform polyhedra there are eight uniform tilings that can be based from the regular square tiling.

Drawing the tiles colored as red on the original faces, yellow at the original vertices, and blue along the original edges, all 8 forms are distinct. However treating faces identically, there are only three topologically distinct forms: square tiling, truncated square tiling, snub square tiling.

## Topologically equivalent tilings An isogonal variation with two types of faces A 2-isohedral variation with rhombic faces

Other quadrilateral tilings can be made with topologically equivalent to the square tiling (4 quads around every vertex).

Isohedral tilings have identical faces (face-transitivity) and vertex-transitivity, there are 17 variations, with 6 identified as triangles that do not connect edge-to-edge, or as quadrilateral with two colinear edges. Symmetry given assumes all faces are the same color.

Squarep4m, (*442) Rectanglepmm, (*2222) Parallelogramp2, (2222) Parallelogrampmg, (22*) Rhombuscmm, (2*22) Rhombuspmg, (22*)            Isoscelespmg, (22*) Isoscelespgg, (22×) Scalenepgg, (22×) Scalenep2, (2222)      ## Circle packing

The square tiling can be used as a circle packing, placing equal diameter circles at the center of every point. Every circle is in contact with 4 other circles in the packing (kissing number). The packing density is π/4=78.54% coverage. There are 4 uniform colorings of the circle packings.    There are 3 regular complex apeirogons, sharing the vertices of the square tiling. Regular complex apeirogons have vertices and edges, where edges can contain 2 or more vertices. Regular apeirogons p{q}r are contrained by: 1/p + 2/q + 1/r = 1. Edges have p vertices, and vertex figures are r-gonal.

Self-dualDuals   4{4}4 or   2{8}4 or   4{8}2 or    Wikimedia Commons has media related to Order-4 square tiling.
1. Tilings and Patterns, from list of 107 isohedral tilings, p.473-481
2. Order in Space: A design source book, Keith Critchlow, p.74-75, circle pattern 3
3. Coxeter, Regular Complex Polytopes, pp. 111-112, p. 136.
• Coxeter, H.S.M. Regular Polytopes, (3rd edition, 1973), Dover edition, ISBN 0-486-61480-8 p. 296, Table II: Regular honeycombs
• Klitzing, Richard. "2D Euclidean tilings o4o4x - squat - O1".
• Williams, Robert (1979). The Geometrical Foundation of Natural Structure: A Source Book of Design. Dover Publications, Inc. ISBN 0-486-23729-X. p36
• Grünbaum, Branko ; and Shephard, G. C. (1987). Tilings and Patterns. New York: W. H. Freeman. ISBN 0-7167-1193-1. (Chapter 2.1: Regular and uniform tilings, p. 58-65)
• John H. Conway, Heidi Burgiel, Chaim Goodman-Strass, The Symmetries of Things 2008, ISBN 978-1-56881-220-5

Fundamental convex regular and uniform honeycombs in dimensions 3–10 (or 2-9)
Family     / / Uniform tiling {3} δ3 hδ3 qδ3 Hexagonal
Uniform convex honeycomb {3} δ4 hδ4 qδ4
Uniform 5-honeycomb {3} δ5 hδ5 qδ5 24-cell honeycomb
Uniform 6-honeycomb {3} δ6 hδ6 qδ6
Uniform 7-honeycomb {3} δ7 hδ7 qδ7 222
Uniform 8-honeycomb {3} δ8 hδ8 qδ8 133331
Uniform 9-honeycomb {3} δ9 hδ9 qδ9 152251521
Uniform 10-honeycomb {3} δ10 hδ10 qδ10
Uniform n-honeycomb {3[n]} δn hδn qδn 1k22k1k21