Re: Caching with custom elements

[Roger H. <rog...@mi...>]

>>> In the renderers, I'm using a custom element to cache an optimized
>>> version of a TriMesh.  The element contains an edit index along
>>> with the
>>> TriMesh reference, so that a stale cache can be detected.  That  
>>> works
>>> fine in principle, though there's a bug at the moment.
>>>
>>> But now suppose I have another similar custom element, say to  
>>> cache a
>>> triangle strip.  When I update the triangle strip, it bumps the edit
>>> index, so the other cache becomes stale.  Which causes the other
>>> cache
>>> to get updated, bumping the edit index, which makes the triangle
>>> cache
>>> stale...
>>>
>>> How can I get out of this infinite loop?  The simplest way, I
>>> suppose,
>>> would be to add a Q3Shared_SetEditIndex function, and use it when
>>> setting these cache elements. Is there a more elegant way I haven't
>>> thought of?
>>> -- 
>>
>>
>> I don't exactly understand what you are trying to do. You have an
>> object A
>> which has two caches B and C, both of which hold the edit index of A.
>> Why would updating B or C update the edit index of A?
>
> Because B and C are custom elements, and Q3Object_AddElement and
> Q3Shape_AddElement update the edit index.
>
>> Or is C a cache of B? If so, C holds the edit indexes of A and B.
>
> Elements don't even have edit indexes, only shared objects do.

I see. Would a Q3Shared_DecrementEditIndex be very slightly less
dangerous?

Roger