Brian Wichmann was inspired by the famous book Tilings and Patterns by Grünbaum and Shephard to constuct patterns on the computer, and then he had the idea to compile an encyclopaedia of tiling patterns, as he found more and more books on the subject. This project developed into a CD-ROM and eventually into a website [ www.tilingsearch.org].

This talk will describe Brian’s collection of over 1,000 patterns. Examples of the type of pattern in the collection are the ones in the Alhambra, consisting of tiles which are polygons – curves are not included. As well as providing a tour of the patterns, Brian will describe how he has organised the collection and how it can be used to locate a particular pattern based on its geometric properties.

Given a large collection locating a specific pattern is not straightforward – many collections in books contain duplicates due to this difficulty. The talk will demonstrate the classification system and illustrate some of the issues. Another technical issue is graphical accuracy; many illustrations in books are poorly-drawn and care is needed to create accurate drawings for the collection. Also care is needed in generating the image of the pattern in a form suitable for downloading; even very high resolution bitmaps can distort the pattern!