For most people, QR codes are a way to store a web link. In reality, we can store more data in QR code than a simple web link. Take a look at the following QR code:
It stores a complete pixel shader. If you drop this QR code in the GeeXLab demo you will get:
And the following one:
produces this effect:
QR code shaders are an original ways to store your GLSL shaders. And for the same price, you get an extra layer of protection (easily crackable with a QR code reader).
All QR codes have been created with the QR code generator available in THIS POST.
This demo requires GeeXLab 0.35.1+ (the latest version is still a good choice) and an OpenGL 3.2 support, sorry for Raspberry Pi users but I was too lazy to convert GL3 shaders to GL2 shaders. The demo is available in the OpenGL 2.1 demopack in the d55-qr-code/qrcode_shader/ folder.
Load the demo in GeeXLab and drag and drop any QR code available in the d55-qr-code/qrcode_shader/qr_shaders/ folder.