The link you show, is a piece of software running on the Pi, that draws some text and graphics, instructed by the Arduino, simple.
The interface on the screen you are having is 99% surely 18-bit TFT as i told you earlier.
If your plan was to use the Libretto as-is and instruct it to show stuff on the screen, then your plot is valid.
Connecting the lcd panel electrically to the arduino, forget it...
// Per.