[Opensim-dev] Supplying IScene instead of Scene for the future region modules mechanism

[Justin Clark-Casey]

Sean Dague wrote:
> Melanie wrote:
>> Hi,
>>
>> as a mid to long range goal, +1, actually.
>>
>> but in the short run, the ability to load and unload regions is 
>> blocked by the existing module API, and to fix this basic piece of 
>> functionality, they need to be migrated to the new API, asap.
>>
>> If this is dragged into a long architectural discussion, we won't 
>> get region restarts for many more months.
>>
>> So, I'd rather see this iteration of the region module API pass 
>> Scene, and remove the old API very soon, and then think about 
>> architecting and refactoring when that is not a blocker to 
>> adding/repairing basic functionality.
> 
> I'd agree with Mel here about lets keep it a bit more open and sloppy
> for now, and start to lock that down once we're on the other side of the
> loader issue.
> 
> We all come to this from different perspectives.  Mine is a lot of scars
> and lost time due to IScriptHost a year ago.  Just about every LSL
> commit required changing IScriptHost and adding back in functions for
> SOP.  Eventually, I just threw out IScriptHost, as it was clear that
> interface was far too premature.
> 
> I think we're a bit premature on IScene at this point.  We know what we
> all would do with it, but leaving the barn door open to other random
> folks abusing the interfaces in ways that we didn't expect is probably
> reasonable at this stage, so we make sure we don't lock off a piece of
> function that's very reasonable to want.
> 
> That being said, breaking Scene into more digestable parts would be a
> *very good thing*.

Definitely.  I've spent quite some time moving things out of Scene myself.  Much of what remains are the much more 
indigestible bits (e.g. land/terrain management, inventory).  I plan to look at these in the course of my normal 
attempts to chip away at the big ball of mud but any help here would be much appreciated.

Switching the region module mechanism seemed to me to be a good opportunity to introduce a Scene interface without 
causing a separate bout of pain later on.  But on hearing some of the rational feedback, I accept that it could still be 
too early to do this.  If people were to treat this interface as a contract they could build against, as Teravus pointed 
out, then it needs to be stable.

Nonetheless, I'm seeing that with the exception of Melanie, the core developers who have posted are in favour of having 
an interface eventually (I presume before 1.0).  So it is coming and if people have to endure some update pain later on, 
well that's the price of building against alpha code.  It's not a huge upheaval either, in most cases it is simply a 
search and replace of Scene with IScene.  When this happens later on I will point back at this discussion as warning.

I'm quite happy to hear arguments against a scene interface, but I will forcefully counter and later ignore any attempt 
by Melanie to bully me off the point with completely exaggerated statements.  We're here to discuss, negotiate and 
compromise in good faith, not to shout at each other across the mailing lists.

-- 
justincc
Justin Clark-Casey
http://justincc.wordpress.com