How do I set position to the middle of the cur screen

I've tried everything.

X= WindowWidth/2

Y= WindowHeight/2

X= LayoutWidth/2

Y= LayoutHeight/2

Scrollx

Scrolly

Nothing works. I thought it would be easier to do such an usual thing. Am I missing something?

Thanks!

I've solved by using the viewport. Here it is in case someone need.

Set position to:

X = abs(ViewportLeft("Interface") +ViewportRight("Interface"))/2

Y = abs(ViewportBottom("Interface") +ViewportTop("Interface"))/2

This will get the current min and max pixels of the screen, sum them and divide by 2 to get the center. Do it for the X and Y axis.