[X3D-Public] Fwd: [FreeWRL-develop] 3D philosophical question

[John A. Stewart]

Dear X3D people;

A FreeWRL user, using the EAI interface, has a conundrum that, on the surface at least, would affect not only EAI, but SAI and Javascript deletion of nodes. 

I don't know the answer to the question, does anyone on this list have an opinion?

Here is the users' question:

> Amongst the actions that happens in my world via the EAI is an 'object
> delete' event.
> 
> It happens in the following sequence:
> mouse over, EAI app gets event
> mouse click, EAI app gets the request
> EAI app sees the object should be deleted
> EAI app sends a remove children request, (and removes the object from
> its internal tables)
> 
> Now comes the conundrum:
> 
> Obviously, from one point of view, the mouse is no longer over the
> disappeared object, and therefore FreeWRL is quite entitled to send a
> mouse exit event; this is what FreeWRL currently does.
> 
> But, from another point of view, it is sending an event tied to an
> object that no longer exists.
> 
> I can program round this; but which is the correct behaviour for
> FreeWRL in this corner case  ?
> 
> At the moment I avoid the problem by ignoring the 'dangling pointer'
> but I might miss a genuine problem.


-----------------------------------------------------------
John A. Stewart
alex.stewart at crc.ca

Network Systems and Technologies - 
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