Parmanoir

Distance field

In image editing, how do you stroke a shape ? By using a distance transform to compute a distance field, which gives the distance to the shape in pixels. Then, painting every distance field value below a stroke width will draw a border.

Image:Distance field.png

This picture is computed using the Meijster algorithm, which works in linear time and computes several kinds of distance functions. Plus, it's simple enough to be implemented in html !

See the canvas implementation or get the code on Github.


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