How do world bounds get calculated?

[snowbillr]

Hi everyone!

I'm playing around with positioning objects using the alignIn method, and am getting confused about how the bounds of the `world` object are being calculated.

Take a look at the codepen here: 

Aligning the text according to `world.bounds`, `world.getBounds()`, and `world.getLocalBounds()` all ends up with different results. Could somebody help me understand why these calls all return different bounds?

(Interesting to note that you can see this happening with the `stage` object too between its `getBounds()` and `getLocalBounds()` methods)

EDIT: This is all happening in the `create` method of the State. Not sure if that has anything to do with it either.

Edited May 10, 2017 by breed

[samme]

All groups have a getBounds() method. It makes a rectangle that covers every visible child of the group, i.e., reaching the leftmost, topmost, rightmost, and bottommost children, wherever they are. It's mostly useful for rendering.

world.bounds is a boundary like fence rather than extent. It's a fixed rectangle equal to the game size (if unmodified) or larger (if you've set it yourself).

For alignment you probably want world.bounds.

[samme]

 

[snowbillr]

Ah, I see! So if I call 'getBounds()' on World it will give me back a rectangle covering all its children. But accessing the 'bounds' property of World gives me its "fence" as you called it. 

Good explanation, thank you!

And A+ codepen example!