Ability to drop 3d objects into 2d UI drop zones

[thestonefox]

A useful feature would be to tag an interactable object as something that can be placed in a 2d UI drop zone. Then when the object is touching the drop zone and dropped into it, the 3d object would be hidden and replaced with a 2d UI image representation of the object.

Once the object is a 2d UI image it would then be able to be dragged around the UI canvas and dropped into other drop zones too if required.

Once the 2d ui object is dragged off a canvas it would hide the 2d ui object and turn back into the 3d interactable object.

[dotlaura]

I've put some time into this and should have time to finish a first pass this week, could you mark it as under development please?

[thestonefox]

Sure, I'll move it to the in progress column on waffle that will add the in progress label. I'm happy to bounce ideas around on the implementation of this one too if you want.