It's never possible for SOG to have no RootPart, except in the first few picosends of the big bang when it's pulled from region persistence or deserialized
The only times when ParentGroup might be null is during regression tests (which might not be a valid thing) and when scene objects are being constructed from the database.
At all other times it's not possible for a SOP not to have a SOG parent.
The root part state is the canonical value, so always send that instead.
Sending conflicting attachments states for non-root parts of a rezzed object is enough to crash the client.
Fixes http://opensimulator.org/mantis/view.php?id=5664.
Many thanks to mewtwo0641 for some fantastic qa work on this one.
This is done by introducing a PresenceType enum into ScenePresence which currently has two values, User and Npc.
This seems better than a SaveAttachments flag in terms of code comprehension, though I'm still slightly uneasy about introducing these semantics to core objects
this is to allow walking on prims. it will be up to the script writer to be sure that there is a continuous path.
currently implemented in osNpcMoveToTarget(), but none of this is final.
This now works again except that it requires a click or avatar mvmt to get going
This is because the ScenePresence.HandleAgentUpdate() method doesn't trigger until the client does something significant, at which point autopilot takes over.
Even clicking is enough to trigger.
This will be improved presently.
However, what happens now is that undo just doesn't do anything when the root prim is selected on its own. This requires more code than just fiddling with undo states.
This involves implementing a boolean in UndoState to signal whether the undo needs to be done for an entire group/linkset or just a single prim
Resizing individual components of linksets is still dodgy.
Resizing still has to be down twice, since for some reason the client is sending two multiobjectupdate packets on every resize except the very first. This applies to single prims and linksets. Need to look into this.
Undo rotation and position appear to be working.
Resizing a single prim appears to be working, though the undo has to be done twice.
Resizing a group of prims still does not work properly - possibly because in the UndoState we don't store a knowledge of when we're resizing a whole group rather than individual prims.
This needs to be addressed.
Unable to get to the bottom of why resizing a mesh fails to properly reset the physics proxy, when toggling phantom does
After a mesh is generated, the existing sculptdata is set to zero in PrimitiveBaseShape to save memory
When phantom is toggled, the sculptdata is regenerated before remeshing.
But on resize, the sculptdata is not regenerated.
So clearly, resetting sculptdata is possible, but haven't quite been able to pin down how this is being done when phantom is toggled.
Many thanks to the aurora project for pioneering this.
This code is almost certainly not bug free, but it does at least appear to handle simple meshes (except when the viewer crashes - but it is beta!).
Changed the experimental capability introduced a couple of commits ago: now sending that extra information as part of the response in the SimulatorFeatures cap.
