How to add the mask (graphic) to group?

[loover]

Hi. How to add the mask (graphic) to group?.  If the mask is added to the group, it no longer masks the sprite inside.

[samme]

It should, if the sprite is a member of the group: examples/v2/sprites/sprite-group-mask

[loover]

In this example, the mask added to the game is used. Not inside a group (e.g. group.add(mask)) that contains boxes.

This not works:

var group = ...;
var box =...;
var mask = ...;
box.mask = mask;
group.add(box);
group.add(mask);

 

[samme]

Just remove 

group.add(mask);

 

[loover]

But what if needed to have mask in group? For easy positioning on the screen, for example? Or when there are many masks for many sprites inside a group?

What are the technical limitations? Nested groups? Because if we call "game.add.graphics()" game adds this graphics into group called "world". Or not?