null would only ever be returned if the item couldn't be located within inventory and this would happen immediately.
In this case, derezzing wouldn't work anyway since there is no item to derez.
This matches behaviour in fatpack crossing, where attachments are cloned before their properties are changed.
This only applies to crossings to simulators running code released before April 2011.
If delete doesn't occur first then the update thread can outrace the IsAttachment = false necessary to save attachments and send hud artifacts to other viewers.
Serialization of attachments requires IsAttachment = false so that correct positions are serialized instead of avatar position.
However, doing this when a hud is still attached allows race conditions with update threads, resulting in hud artifacts on other viewers.
This change sets SOG.IsDeleted before serialization changes take place (IsDeleted itself is not a serialized property).
LLClientView then screens out any deleted SOGs before sending updates to viewers.
This involves three steps
1) Return gracefully in UrlModule.HttpRequestHandler() instead of throwing an exception when the url cannot be found in its index
2) Return true instead of false in HasEvents() if no matching request is found in the map. This call will only happen in the first place for raced requests.
3) Return a 404 in GetEvents() if the request is not in the index, rather than a blank 200 OK.
Many thanks to Tom Haines in http://opensimulator.org/mantis/view.php?id=6051 for doing some of the work on this.
Previously, setting IsAttachment to false then true was necessary to serialize the updated attachment object information.
However, UpdateAttachmentPosition no longer does this update.
Whilst IsAttachment is set to false there is a race condition where the update thread can wrongly send hud object updates to clients that do not own the hud, resulting in screen artifacts.
It's a valid configuration not to have these modules, but I think it's still worth logging the fact that certain permissions won't work (always return true)
Change SOP.SendFullUpdateToClient() and SoundModule.PlayAttachedSound() to use this rather than different magic number formulations.
This also corrects a bug in PlayAttachedSound() where the code assumed that all attachment points over 30 were HUDs.
It appears this is no longer true with Neck and Root (Avatar Center)
Stop checking IsLoggingOut on these listeners, if called with a root agent then we always want to perform these actions.
This covers cases where the client is closed due to manual kick, simulator shutdown, etc.
This is always done as part of Scene.RemoveClient()
Also refactors try/catching in Scene.RemoveClient() to log NREs instead of silently discarding, since these are useful symptoms of problems.
If active, the physics module can return arbitrary stat counters that can be seen via the MonitoringModule
(http://opensimulator.org/wiki/Monitoring_Module)
This is only active in OdeScene if collect_stats = true in [ODEPhysicsSettings].
This patch allows OdeScene to collect elapsed time information for calls to the ODE native collision methods to assess what proportion of time this takes compared to total physics processing.
This data is returned as ODENativeCollisionFrameMS in the monitoring module, updated every 3 seconds.
The performance effect of collecting stats is probably extremely minor, dwarfed by the rest of the physics code.
Also fixes the log warning from ResetInTransit() if the state is cleared direct from Transferring or ReceiveAtDestination, as pointed out in mantis 5426
