UI

This is an extremely involved topic, so for now, it's just a collection of facts. It will be expanded upon later.

Custom RootWindow

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Pitfalls

• If the game crashes with an assertion error saying lockCount <= 0 before leaving a level, it's because a Window somehow lost its place in the hierarchy and cannot be found by the RootWindow to destroy clean it up.
• Never store references to Window classes as member variables in Actors. Non-actors do not clear their references stored on actors when destroyed, that's an actor-to-actor grace only. Also, windows are transient and you'd be saving a null pointer to disk.