Hi guys! Sorry if this is the wrong place or if there was something obvious to google but I'm not finding what I need and I don't know Github well enough to find the code that runs G2 and G3 outputs in the RepRapFirmware.

Before anyone says that it's stupid to be reinventing the wheel, I'm just doing this as a learning experience in my off time. Simplest way to help would probably be to just point me to where I can find the code for a RepRap and reverse engineer it myself, but if someone could go into the theory of how it works that would also be great!

I have some ideas already on how to accomplish the G2/3 moves but they would be very computationally expensive on the architecture I'm trying to use (ATTiny, again I know its not the easy/right path, I'm just pushing my boundaries). I'm hoping there's something clever that I can do without resorting to doing trig calculations as or lookup tables as I'm almost out of program memory and don't have the MIPS to spare as is. My first thought for something clever was to just use linear acceleration akin to S-Curves, but I have since learned that the typical S-Curve is not sinusoidal and so ramping the velocity up and down linearly will not help.

Thanks for any guidance and sorry if this is too rambly...