you can consider the origin to be whatever you want. I, for example, consider (0,0) to be bottom left.It's just a matter of how you handle the coordinate system, and how your Renderer draws it. If you want the oject to be at the center, then, while drawing, you'll probably say (center + pos). To consider (0,0) as the bottom left position, just use Pos.

I personally prefer the bottom-left coordinate system, because it makes things easy

And also, it's a good idea to keep some conversion constants : Meters2Pixels and Pixels2Metres to adapt to different resolutions and to have finer control over the simulation.
Cheers!
PS- PM me if you have some doubts or something

you can consider the origin to be whatever you want. I, for example, consider (0,0) to be bottom left.It's just a matter of how you handle the coordinate system, and how your Renderer draws it. If you want the ibject to be at the center, then, while drawing, you'll probably say (center + pos). To consider (0,0) as the bottom left position, just use Pos.

I personally prefer the bottom-left coordinate system, because it makes things easy

And also, it's a good idea to keep some conversion constants : Meters2Pixels and Pixels2Metres to adapt to different resolutions and to have finer control over the simulation.
Cheers!
PS- PM me if you have some doubts or something