Unexpected save/load cycle failure

[zaimoni]

This change isn't actually landed in RS Revived's trunk (caught in testing and locked down).

It would have been useful to switch Actor over to ISerializable (this enables cache variables that don't reach the savefile, which would be useful for dealing with some profile-hot code called from pathfinding).

But ... no. Map::m_ActorsList suddenly breaks down (correct length, but all entries null -- crash during load). No relevant search engine hits (there are a few from 2012 or so but they are not from "doing things by the book").

Diagnosis steps remaining:

• Does force-upgrade of Visual Studio fix this? (no)
• If force-upgrade failed, does full rebuild fix this? (no)

[zaimoni]

Problem appears to be an undocumented change in behavior triggered by deriving from ISerializable: docs.microsoft.com/en-us/dotnet/standard/serialization/custom-serialization?view=netframework-4.8 . There's a more modern approach (era .NET 2.0) that might help here, but the archaism actually is needed by RS Revived.

[zaimoni]

Other notes re .NET Core 3.0:

• System.Diagnostics.Activity is new (and can collide with djack.RogueSurvivor.Data.Activity). Mechanical workaround.
• Unlike Windows Presentation Framework, System.Random is not serializable in .NET Core 3.0; this is a blocker for porting to .NET Core.

[zaimoni]

Five-year obsolete overview of C# standard library savefile options: manski.net/2014/10/net-serializers-comparison-chart/ .