I want to start learning making an addon by editing something simple that already works.
I need code that has a very simple 'window' on the screen (frame?), with 1 single number that is printed, like those you see on those 'world coordinates' addons or "speed meter' addons (a small draggable rectangle).
Also, can such a thing be restricted to lua allone? I do not want to deal with XML. I'm used to 'raw' code in C, C++, perl, bash. Never was confortable with "HTML".
I think I will probably figure out the event code that I will need to draw the number printed.