Which algorithm does Marlin use to create arcs?

Question

I'm writing a paper about a plotter (I use a Prusa i3 with a custom "extruder" aka pen). And I'm supposed to write about the algorithms I/the plotter use(s). I tried reverse engineering, but since I'm not very experienced with this technique I wasn't successful. So I'm looking for the algorithm that Marlin uses for its G2/G3 commands.

Have you looked at [Marlin_main.cpp](https://github.com/MarlinFirmware/Marlin/blob/RC/Marlin/Marlin_main.cpp), specifically t,e ``plan_arc`` function? — Tom van der Zanden, Apr 02 '16 at 09:21

score 4 · Accepted Answer · edited May 27 '16 at 03:52

4

The algorithm is based on the "Vector rotation by transformation matrix", and this solution is based on a solution from Jens Geisler. The formula for clockwise rotation is:

More information about the vector rotation can be found on Wikipedia.

edited May 27 '16 at 03:52

Peter Mortensen

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answered Apr 03 '16 at 15:58

Maaajaaa

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Which algorithm does Marlin use to create arcs?

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