I have a Python program using Kivy to generate the GUI running in a window on a Raspberry Pi running the normal Raspberry Pi OS DeskTop & X Server.
I want to convert this Python / Kivy program to run in a secure kiosk mode.
But after stopping the Raspberry Pi's X Server and Desk Top from starting, I have not discovered the proper way to alter the Pyton / Kivy program to write directly to the FrameBuffer. The goal is make what was once displayed in the application's window to be sent to the FrameBuffer to be displayed directly on the LCD screen.
I am using a Raspberry Pi 4 and the standard (official) Raspberry Pi 7 inch touch screen which has a FrameBuffer that shows up as /dev/fb0.