Libgdx Scaling Action with Keeping The Center Position

Question

I'm creating a pop out action effect on a window after I click on some button in LibGdx.

May I know, Is there any methods available to scale the actor, in a way that keeping its center position at the center (scales in both direction of x and also both direction of y)?

addAction(sequence(scaleTo(1.3f,1.3f,0.2f),scaleTo(1f,1f,0.2f)));

This is the basic scaling method I used.

↑

O →

But I want something like this:

......↑

← O →

......↓

Answer 1

You need to set actor's origin to its center. First set the size, and then call:

actor.setOrigin(Align.center);

Note, that if your actor is a Table (and classes like Button, ImageButton extend Table), then you need to call:

actor.setTransform(true); // But keep in mind that has a performance impact "because {@link Batch#flush()} must be done before and after the transform"