TWO ways to scroll the background:

Script (CPU)

Shader (GPU)

This is a more traditional method.

It requires us to write a script to continuously update

and reset the position of the tiles on the screen.

The work is done by the CPU and so could impact the performance.

This is an alternative method

It requires us to write a shader script

to continuously update the position of the tiles over time.

The work is done by the GPU and is faster as the GPU processes in parallel.