Gurney-7B

f7b-colour
A minimally-useful tracing of the standard numerals embossed
on credit cards. The geometry should be checked against ISO/IEC 7811—1:2002 should these data be used for official purposes. No claims of compliance are made here.

As there are only 10 digits in this font, encoding it as a digital
form (TTF, OTF, or otherwise) is left as an exercise for the reader.

Files

  1. f7b-colour.svg – an A4 sheet with all 10 digits presented as a
    poster. Each digit is approximately 1284% standard size.
  2. eps folder – PostScript source files. Each outline is approximately 5695% standard size, which is appropriate for a glyph in FontForge.

Workflow

The rough character outlines were created as short scripts in Python,
using the Shapely library to handle geometry. A confusing array of support tools (including, but not limited to: QCAD, wellknown
and OGR added the arcs and fillets. The more complex arc intersections were calculated using GeoGebra. Finally, the
outlines — at this point, mostly in the form of PostScript Level 2
arct commands — were hand-keyed into the EPS files included here.

Notes on the data

  1. There are some typos in the published coordinates, particularly in
    the “1” glyph. Whether these are genuine errors or
    trap streets‘, is hard to tell. The glyphs presented here are intended to be visually accurate
  2. The published coordinates of the “8” glyph indicate that it is
    only 97.6% as tall as the other digits. This has been carried
    through here.

Also on github: scruss/Gurney-7B

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