Looking for advice on implementing e-ink guis

Other Hardware Displays
1

I hope my question is not too general. Just looking for some startup advice as this is my first time using an e-ink display.

I am using the Waveshare 2.9" e-Paper Module V2 and a KY-040 rotary encoder and I would like to know the usual (dare I say best?) way to design/implement a GUI interfaces, since this is my first time with this display. Let me give an example.

A menu display with 4 buttons (eg rectangle boxes). Each button has an icon and some graphics. I can use the rotary encoder to move from button to button, and then select one. As each button is selected, the border gets thicker. There are two buttons on each screen at the bottom for back and home. In the picture below, Option 2 is selected.

Screenshot from 2025-05-23 19-01-58
Screenshot from 2025-05-23 19-01-581248×551 53 KB

My question is, is it better to draw each element on the screen as graphics and text, or convert each button to an bit map and just swap out the selected version from the un-selected version as the rotary encoder moves? I have seen tutorials using both methods. The first option seems time consuming, and the second seems resource intensive.

I am using the exGPD2 library for the display and an ESP32S3 for the processor. Is there a better graphics library?

2

have a look at the TFT_eWidget library

3

Redrawing the border around the button as a graphic element would not seem to be too time consuming, particularly considering how slow most e-ink displays are to begin with.