Created to test the HAGL graphics library. You need SDL2 to run the demos.
$ brew install sdl2 # macOs
$ sudo dnf install SDL2-devel # Fedora, Rocky etc
$ sudo apt-get install libsdl2-dev # Debian based distros
$ git clone https://github.com/tuupola/sdl2_effects.git --recursive
$ cd sdl2_effects
$ make clean && make
$ ./demo
HAGL is hardware agnostic. You can run the demos also ESP32 based boards.