esp-idf-lib VS hagl

External libraries are added as 'components'. I suggest you take a look at the great work by UncleRus et al, you can add the repository as a git submodule and add the items you want to use as a 'REQUIRES' statement in your CMakeLists.txt file.

The library by UncleRus has an example and it mentions you should (and this probably is right).

The library is: https://github.com/UncleRus/esp-idf-lib and the example uses the DHT (Humidity sensor) library.

My first idea to solve this was to create my component which implements a mutex to access each I2C bus. Now, when I was searching github for previous implementations, I saw this repo https://github.com/UncleRus/esp-idf-lib. Not only does it have the solution for I2C it also has components for some of the sensors I am using.

With some research found out the library actually works correctly when run outside of platformio with idf.py as stated here: https://github.com/UncleRus/esp-idf-lib/issues/46

ST7789 is a MIPI DCS chip so you can use HAGL with MIPI DCS HAL. There are a couple of examples and a video or two. Also sorry for blatant self promotion.

ST7789 is a standard MIPI DCS chip so you could HAGL with the MIPI DCS HAL. In addition to drawing rectangles etc I have used it four couple of proof of concept apps such as video player and old school demo effects.

Looks great! Don't worry about hours used or how many people will use it. Think of it as a learning experience. I did something similar with the only goal being to learn the C language.