Avik Das discusses setting up a TFT LCD screen on a Raspberry Pi to create a lightweight heads-up display without the need for a desktop environment. He explains the concept of framebuffers in Linux and provides detailed instructions on configuring the framebuffers to display graphics on different screens. Das walks through writing a C application to output directly to the Linux framebuffer, and introduces raspi2fb, a program that mirrors the Raspberry Pi display and provides tips on using Raylib, a high-level library, for graphics rendering. He also describes calibrating a touchscreen for integration with Raylib. Note: The article includes technical details and requires some programming knowledge.
https://avikdas.com/2019/01/23/writing-gui-applications-on-raspberry-pi-without-x.html