C Resources

Http
https://github.com/vinbero/vinbero

Bluetooth

GPIO

GTK (gui)
https://www.raspberrypi.org/magpi/issues/c-gui-programming/

OpenCL
https://github.com/doe300/VC4CL

Gui without Desktop
https://medium.com/@avik.das/writing-gui-applications-on-the-raspberry-pi-without-a-desktop-environment-8f8f840d9867

http://raspberrycompote.blogspot.com/2012/12/low-level-graphics-on-raspberry-pi-part_9509.html

https://github.com/matusnovak/rpi-opengl-without-x

Blowfish
https://github.com/HybridEidolon/saredit/tree/master/src/blowfish

Pixel Art Editor
https://github.com/mananapr/pxlart

Hex Editor
https://github.com/krpors/hx

OLED Controller
https://gecko05.github.io/2019/06/23/rgb-library.html