Glider control mode?

I was wondering if anyone has a recommended approach to glider control? I know previous work has been done with thermal finding by some, however I wanted to experiment with it myself using offboard computation.

Does anyone have a recommended mode setup to implement high level navigation control under a pitch / glide polar restriction? I can sed the max throttle to zero (I think this still allows flying in manual mode with normal throttle control?), but I do not know of a way to to do goal pitch commands.

Thank you,