Allow for event bubbling during selection

[zaalbarxx]

Hi, today I was fiddling with our implementation of seat allocation tool to improve its performance. And while I succeeded with that by grouping objects inside the bigger groups and caching these (less caches to create, thus better performance) the new problem arisen.
Let's consider this example:

In this example all of the seats are within single group which has selectable: true. The current implementation of selection in fabric v5 always checks only the top-level objects when looking for intersection, it also does not provide any option to get the box created for selection (so the selected objects could be calculated by yourself). So in this example when I make selection it will return only single Group object. I believe that when the nested objects also have the selectable: true flag then these objects should also be taken into account. Same goes for events like mouseup where target will always be the "top-level" object.
Is there any workaround for this except overwriting the whole implementation of _collectObjects method (for selection) and other tweaks for the mouse up ?

[asturur]

What is your end goal? knowing which objects are inside the rectangle or select them?

[zaalbarxx]

My end goal is to know which nested objects have been selected, with that knowledge, I assume, I would easily be able to do the rest (like highlighting etc.). Basically, from my perspective, it would be good if, for example, the selection:created event could return selection x1,y1,x2,y2, that alone would most likely be sufficient to calculate the intersecting items, with any logic you'd want.

I don't specifically want to select the items in Fabric meaning (like showing the transforming options).

Additionally, the same thing happens for mouse events. Always the top-level group will get returned, but I suppose there is some way here to use the mouse event and transform it to Fabric coords and calculate the intersecting nested item inside the target group?

[zaalbarxx]

@asturur any update on this ?