

A fast gesture recognizer based on the PennyPincher algorithm, written in Swift - fe9-lix
http://fe9lix.github.io/PennyPincher/

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bazzargh
The paper isn't linked from the article, here it is:
[http://www.eecs.ucf.edu/isuelab/publications/pubs/gi2015_eug...](http://www.eecs.ucf.edu/isuelab/publications/pubs/gi2015_eugene.pdf)

It's a neat trick: instead of trying to work with the (x,y) points of a
gesture, and worrying about rescaling/translating to match, it resamples the
template and gesture into n vectors each with the same length, and the
comparison is then just the sum of the angle differences in corresponding
vectors in the two lists.

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crusso
So, gestures that involve strokes radially outward or inward might be fairly
difficult to distinguish?

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bazzargh
I imagine it would have difficulty with letters that differ only in scale (x,
X) but for things like varying stroke order, stroke direction to achieve the
same mark - which is I think what you're getting at? - the paper suggests just
recording more templates for the glyph works well.

