bugfix(ghostobject): Add Ghost Objects of the local player to the scene correctly after loading a savegame

[xezon]

• Fixes Ghost buildings after loading a saved game #1923
• Follow up for feat(client): Implement Player Observer and fix shrouding and ghost object issues #1569

This change fixes wrong ghost objects shown after loading a savegame.

This happened because the original Xfer code added ALL ghost objects to scene, including those that do not belong to the local player.

This issue does not happen in Retail Game, because it did not record snapshots for all players and was disabled behind the DEBUG_FOG_MEMORY macro. We enabled this functionality with #1569 so that we can track the ghost objects for all players.

I moved the fix to loadPostProcess because that is a cleaner location for it.

TODO

• Replicate in Generals

[xezon]

@greptileai

[greptile-apps]

Greptile Overview

Greptile Summary

This PR fixes a bug where wrong ghost objects were shown after loading a savegame. The issue occurred because the original code in xfer() added ALL ghost objects to the scene, including those that don't belong to the local player.

• Removed premature addToScene() calls and removeParentObject() logic from the xfer() method
• Moved the scene addition logic to loadPostProcess() where it's executed after all deserialization is complete
• Added proper local player filtering by calling addToScene(playerIndex) only for the local player
• The removeParentObject() call is now conditional on successful snapshot addition

This fix addresses issue #1923 and is a follow-up to PR #1569, which enabled ghost object tracking for all players (previously disabled behind DEBUG_FOG_MEMORY in retail).

Confidence Score: 4/5

• This PR is safe to merge with minimal risk
• The changes are well-structured and address a specific bug by moving logic to a more appropriate location with proper player filtering. The identical implementation in both Generals and GeneralsMD ensures consistency.
• No files require special attention

Important Files Changed

Filename	Overview
Generals/Code/GameEngineDevice/Source/W3DDevice/GameLogic/W3DGhostObject.cpp	Moved ghost object scene addition logic from xfer() to loadPostProcess() with proper local player filtering
GeneralsMD/Code/GameEngineDevice/Source/W3DDevice/GameLogic/W3DGhostObject.cpp	Moved ghost object scene addition logic from xfer() to loadPostProcess() with proper local player filtering

Sequence Diagram

sequenceDiagram
    participant Save as Savegame System
    participant Xfer as Xfer (Load)
    participant Ghost as W3DGhostObject
    participant Scene as 3D Scene
    participant Parent as Parent Object

    Note over Save,Parent: Loading Savegame Process
    
    Save->>Xfer: Load savegame data
    Xfer->>Ghost: xfer(xfer)
    
    Note over Ghost: Loop through all players
    Ghost->>Ghost: Create snapshots for ALL players
    Note over Ghost: ❌ OLD: Added ALL snapshots to scene<br/>✅ NEW: Only create snapshots, don't add
    
    Xfer->>Ghost: loadPostProcess()
    Ghost->>Ghost: Get local player index
    Ghost->>Ghost: addToScene(localPlayerIndex)
    
    alt Snapshot added for local player
        Ghost->>Scene: Add local player's snapshot
        Scene-->>Ghost: Success
        Ghost->>Parent: removeParentObject()
        Note over Parent: Remove real object<br/>since ghost is visible
    else No snapshot for local player
        Note over Ghost: Keep real object in scene
    end

Loading

[Skyaero42]

Code looks good - I haven't tested it though.

[xezon]

Replicated in Generals without conflicts.

I did another pass on the code comment and preserved the EA comments.

[stephanmeesters]

Tested with the savegame that was included in the original issue.

Apparently the building was being destroyed as the samegame happened, as can be seen by the rangers coming from it. With the fix the ghost building is gone and you see some of the rubble from the destroyed building

Before:

After: