how does the LUT work?

[husnoo]

Does anyone know why these two have such a different approach to LUTs -

https://github.com/Bodmer/EPD_Libraries/blob/master/epd4in2/epd4in2.cpp
https://github.com/Bodmer/EPD_Libraries/blob/master/epd2in9/epd2in9.cpp

The former has lut_vcom0, lut_ww (white->white), lut_bw (black->white), etc, whereas the latter has lut_full_update and lut_partial_update.

Does this just mean they have different controllers? Would the latter one have built-in versions of _ww, _bw, etc that we're just not seeing in the code?