The Layout behavior allows you to position objects easily. You can
position an object relative to its parent (either the Scene or a
another object) by using a position specifier for each of the axes.
The position specifier can be one of 'min', 'center' or 'max'. The default
specifier is 'center'. You can also add a modifier to the position in pixels
('min+5'), a percentage ('min+10%') or meters ('min+1m'). Finally, you can
choose the location of the anchor on the object you are trying to position
by using the 'my' parameter.
You must specify at least one axis on the 'at' parameter.