Still can be done with GDX.
Something like this..
Code:
private void resize()
{
float x = Gdx.graphics.getWidth();
float y = Gdx.graphics.getHeight();
float changeX = x / assumeX;
float changeY = y / assumeY;
position = new Vector2( position.x * changeX, position.y * changeY );
width = startWidth * changeX;
height = startHeight * changeY;
bounds = new Vector2 ( position.x, ( Gdx.graphics.getHeight() - position.y ) - height );
}
Basically what you're doing is taking every object generated and running it through something that increases/decreases depending on the change in the x/y values in your resolution. The further it is from the native, the bigger it will be. When checking of something is somewhere or putting something somewhere, always code it as your desired resolution but run it through a resize function before displaying it or letting it interact with the rest of your app.