This is a minimal version of a program to compute the terdragon curves. I have a program with more detailed tiles here. However, that program is quite slow. This version does not give any details to tiles, so much slow code can be ditched (though when I have time I could also just improve it). There is little "rounding" error at the ends of the curves, which to fix, I would have to colour each "cell" in potentially two colours, and make some adjustments to code. Since in the limit, or for larger values of the scale this boundary error is not really visible, I've not sorted this out, though it would give nicer tessellations for small levels of the scale if I get round to that. As it is, the tesselation for small levels consists of three tile types.
This was written on a mac, and works in Chrome. It might not work on other devices.
Controls might be a bit of a pain on top of the image, so you can change them to be above it by clicking a button.
This version is based on a grid of squares. The squares can be transformed to be a grid which is a subset of equliateral triangles. As triangles, the picture is "correct", though as squares, it corresponds better to how the algortihm actually works, so you can move the blue dot to distort if you want to see as a union of squares.