It looks like it just uses the raw RGB values from the image, sampled in a 25x25 grid spanning the image. The orientation isn't random, but is chosen to avoid the sharper regions of the image, preferring to pick the points representative of smoother areas of colour.
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The background image is here: http://lab.hailpixel.com/static/1/img/box.jpg
It looks like it just uses the raw RGB values from the image, sampled in a 25x25 grid spanning the image. The orientation isn't random, but is chosen to avoid the sharper regions of the image, preferring to pick the points representative of smoother areas of colour.
This is exactly how I did it. The orientation on the triangles is chosen to minimize the "color distance" between connecting edges.