feat: snapshot spawn pre-requisite 2

[jeffreyrainy]

This separates the spawning of NetworkList from the value updates. It adds a "full" event to the NetworkList which consists of sending the whole list. It gets performed when the variable is marked dirty.

We also add a mechanism to mark all the NetworkVariables of an object dirty and remove the serialization of the NetVars with the spawn command.

The HiddenVariable test is also modified to not rely on the count of events, but rather on the actual values after each step of the test. This is better because it tests the right thing, but also because it allows for timing differences. The spawn could occur before the value update or simultaneously. As such, relying on the count of events would be incorrect.

[LukeStampfli]

Problably stupid question because I'm misunderstanding this. But this causes the full list to be serialized to all connected clients whenever IsDirty is set to true? Wouldn't that happen too often? E.g. when:

• An item is added / removed from the list
• The object becomes visible on any client.

[jeffreyrainy]

On the first point, my understanding is that NetworkList.Add() will do:

            m_List.Add(item); // add to the underlying container

            var listEvent = new NetworkListEvent<T>()  {
                Type = NetworkListEvent<T>.EventType.Add,
...            }; // create an event

            HandleAddListEvent(listEvent); // handle the event
        }

This then does:

        private void HandleAddListEvent(NetworkListEvent<T> listEvent)
        {
            m_DirtyEvents.Add(listEvent);
            OnListChanged?.Invoke(listEvent);
        }

and as such does not mark the list dirty. So, dirty means: needs complete refresh, and m_DirtyEvents means need incremental changes.

On the second point, yeah. There's a price to pay here. But until AoI is integrated and we start automatically hiding/showing object, I think these will be very infrequent.

[LukeStampfli]

Okay yeah that makes sense

[mattwalsh-unity]

I follow, but would add:

• please add a comment to the effect of "IsDirty means totally dirty, else m_DirtyEvents means incremental
• but I have a hunch this will bite us and should be re-visited

[LukeStampfli]

I thought we were going to remove NetworkShow/Hide in this release?

[jeffreyrainy]

I thought we were going to remove NetworkShow/Hide in this release?

We can only(reasonably) do that once we have AoI. The theory is that even though the whole show/hide mechanism has technical debt, the API itself is reasonable. So, when proper AoI-based show/hide drops in, the NetworkShow/NetworkHide API becomes an helper mechanism with AoI.

e.g.: User can put rules, like "hide zombies that are far and not green, but not from my team" via AoI, but also "Hide this Zombie for this player, I know what I'm doing" via NetworkHide.

[LukeStampfli]

Still a bit confused because I thought we rip out the visibility system @mattwalsh-unity but the PR itself here looks good.