bugfix(saveload): Serialize base state machine in TurretStateMachine and DozerActionStateMachine

[bobtista]

Fixes:

• Turret state machines revert to their default state after loading a save game
• Dozer action state machines revert to their default state after loading a save game

TurretStateMachine::xfer and DozerActionStateMachine::xfer override the base but never call StateMachine::xfer, so the active state ID, sleep timer, goal, and lock flag are never serialized. On load the machine snaps back to its default state.

Now both chain to StateMachine::xfer/loadPostProcess, matching every other state-machine subclass. Bumped to version 2 and gated the base call so existing version-1 saves still load. Audited all 18 StateMachine subclasses — these two were the only ones missing it.

Todo:

• Replicate to Generals

[greptile-apps]

Greptile Summary

Fixes missing StateMachine::xfer / loadPostProcess chains in TurretStateMachine and DozerActionStateMachine, which caused both machines to silently snap back to their default state on save-game load. The fix is applied symmetrically to both the Generals/ and GeneralsMD/ codebases (note: the PR description's "Todo: Replicate to Generals" checkbox is already completed in this diff).

• Both xfer overrides are bumped to version 2 and call StateMachine::xfer inside a version >= 2 guard, preserving backward compatibility with existing version-1 saves and retail-compatible saves (RETAIL_COMPATIBLE_XFER_SAVE keeps the version at 1).
• Both loadPostProcess overrides now chain to StateMachine::loadPostProcess() unconditionally; the base implementation is a no-op, so this is safe for all save versions.
• The pattern matches every other corrected state-machine subclass in the codebase (e.g., AIGuard, AITNGuard, AIGuardRetaliate).

Confidence Score: 5/5

Safe to merge — the change strictly adds missing base-class chaining behind a version guard, leaving all existing save files loadable without any behavioral change.

The version bump is correctly gated so v1 saves continue to load as before. The RETAIL_COMPATIBLE_XFER_SAVE guard preserves retail-save compatibility. StateMachine::loadPostProcess is a no-op, making the unconditional chain in both overrides harmless. The same pattern is already established across other corrected subclasses in the codebase. Both codebases (Generals and GeneralsMD) are updated consistently.

No files require special attention.

Important Files Changed

Filename	Overview
GeneralsMD/Code/GameEngine/Source/GameLogic/AI/TurretAI.cpp	Bumps TurretStateMachine xfer to version 2; gates StateMachine::xfer call behind version >= 2 guard; adds StateMachine::loadPostProcess chain
GeneralsMD/Code/GameEngine/Source/GameLogic/Object/Update/AIUpdate/DozerAIUpdate.cpp	Bumps DozerActionStateMachine xfer to version 2; gates StateMachine::xfer after existing m_task xfer; adds StateMachine::loadPostProcess chain
Generals/Code/GameEngine/Source/GameLogic/AI/TurretAI.cpp	Mirror of GeneralsMD fix — identical version bump and base-xfer chain for TurretStateMachine
Generals/Code/GameEngine/Source/GameLogic/Object/Update/AIUpdate/DozerAIUpdate.cpp	Mirror of GeneralsMD fix — identical version bump and base-xfer chain for DozerActionStateMachine

Sequence Diagram

sequenceDiagram
    participant Caller
    participant DerivedSM as TurretStateMachine / DozerActionStateMachine
    participant BaseSM as StateMachine

    Note over Caller,BaseSM: Save (version 2)
    Caller->>DerivedSM: xfer(xfer)
    DerivedSM->>DerivedSM: "xferVersion(&version, 2)"
    DerivedSM->>DerivedSM: "xferUser(&m_task) [DozerOnly]"
    DerivedSM->>BaseSM: "StateMachine::xfer(xfer) [version>=2]"
    BaseSM->>BaseSM: "xferVersion(&v, 1)"
    BaseSM->>BaseSM: xfer sleepTill, defaultStateID, curStateID, snapshot, goal, lock

    Note over Caller,BaseSM: Load (version 2)
    Caller->>DerivedSM: xfer(xfer)
    DerivedSM->>DerivedSM: xferVersion reads 2
    DerivedSM->>DerivedSM: "xferUser(&m_task) [DozerOnly]"
    DerivedSM->>BaseSM: "StateMachine::xfer(xfer) [version>=2]"
    BaseSM->>BaseSM: restores m_currentState, goal, lock

    Note over Caller,BaseSM: Load (version 1 - legacy save)
    Caller->>DerivedSM: xfer(xfer)
    DerivedSM->>DerivedSM: xferVersion reads 1
    DerivedSM->>DerivedSM: "xferUser(&m_task) [DozerOnly]"
    Note over DerivedSM: base xfer skipped - machine resets to default (old behaviour preserved)

    Note over Caller,BaseSM: loadPostProcess (all versions)
    Caller->>DerivedSM: loadPostProcess()
    DerivedSM->>BaseSM: StateMachine::loadPostProcess() [no-op]

Loading

_{Reviews (5): Last reviewed commit: "fix(savegame): serialize base StateMachi..." | Re-trigger Greptile}

[Skyaero42]

Nice find

[xezon]

I observed save bug in USA 02: after save (not load) the Aircraft Carrier loses its target. Will this change fix that?

[bobtista]

I observed save bug in USA 02: after save (not load) the Aircraft Carrier loses its target. Will this change fix that?

is there an issue and repro steps you can point me to?

[xezon]

is there an issue and repro steps you can point me to?

Repro:

• Load USA 02
• Select Air Craft Carrier
• Force Fire terrain (see planes attacking relentlessly)
• Save Game (No Load)
• Observe planes

Result:

Planes stop attacking target.

[xezon]

Ok

[bobtista]

is there an issue and repro steps you can point me to?

Repro:

• Load USA 02
• Select Air Craft Carrier
• Force Fire terrain (see planes attacking relentlessly)
• Save Game (No Load)
• Observe planes

Result:

Planes stop attacking target.

#2996 :)

[xezon]

Needs to be replicated to Generals.