fix(savegame): rebuild shroud grid on load to clear fog over own base

[coolswood]

Description

Fixes fog of war creeping over the player's own base after loading a save in Generals Challenge mode.

Symptom: After saving → loading a challenge save, fog of war covered the player's own buildings within ~5-10 seconds. The player's own structures became gray "previously seen" ghosts that could no longer be selected or controlled.

Root cause

After a save load, PartitionManager restores the per-cell shroud counters (m_currentShroud) and the pending undo-queue from the file, but nothing re-applies object lookers — PartitionManager::loadPostProcess() was an empty stub.

When the restored undo-queue drains (~m_unlookPersistDuration = 30 frames later), removeLooker fires at each queued position. Static structures never re-look, so their cells drop to FOGGED (gray ghost / unselectable). The restored m_partitionLastLook and the cell counters also disagree, so any later handleShroud() would double-count.

A relationship-loss hypothesis was investigated first and disproved: brute-forcing all players to mutual ALLIES on load did not fix it, because relationships only matter inside Object::look(), which is never called after load.

Changes

GeneralsMD/Code/GameEngine/Source/GameLogic/Object/PartitionManager.cpp

Implemented PartitionManager::loadPostProcess() (previously an empty stub) by mirroring the established TerrainLogic::setActiveBoundary rebuild pattern:

1. Drain the restored undo-queue so lingering undoes don't fire after rebuild
2. Snapshot explored (FOGGED) and permanently-revealed (CLEAR) cells via storeFoggedCells
3. Release ghost-object partition data
4. Invalidate every object's sighting state (friend_prepareForMapBoundaryAdjust) so the later unlook()/unshroud() are no-ops instead of double-undoes
5. Tear the cell grid down to the all-shrouded default (reset() + init())
6. Restore permanently-revealed cells
7. Re-look every object (friend_notifyOfNewMapBoundary → each object owns exactly one live looker)
8. Restore explored cells + ghost objects + refreshShroudForLocalPlayer()

After this the undo-queue is empty, every live object owns its looker, and static structures stay CLEAR permanently.

GeneralsMD/Code/GameEngine/Source/GameLogic/System/GameLogic.cpp

Guarded the challenge-mode relationship-setup block in tryStartNewGame() with loadingSaveGame == FALSE, so it cannot overwrite serialized relationships on load.

Verification

• macOS build (macos-vulkan), Zero Hour target
• Loaded the previously-broken challenge save (00000062.sav, ~6.7 MB)
• Observed for 30+ seconds: fog no longer creeps over the player's own base
• Buildings remain selectable and controllable
• Previously-explored-but-not-visible areas stay gray (FOGGED), not black (SHROUDED) — confirms restoreFoggedCells preserves explored state

Notes

• Zero Hour only — Generals Challenge is an expansion feature, so no backport to the base game.
• This is a load-path bug, not a relationship/diplomacy bug. The relationship guards are defensive; the actual fix is the shroud rebuild.

[fbraz3]

Hey @coolswood thank for the PR.

Could you please fix the build pipeline? thanks!

[coolswood]

Looks like the macOS ZH build failed, but it's not the code — vcpkg couldn't download freetype from gitlab.freedesktop.org (HTTP 504 on all 3 retry attempts). The build never even got to compiling the game.

The same change builds fine on the other jobs, including macOS Generals and Linux ZH, so this looks like a transient network issue with the GitLab mirror.

Would someone with access mind re-running the failed job? Should go green once the mirror is back up.

[Caball009]

Duplicate of https://github.com/TheSuperHackers/GeneralsGameCode/pull/2892/changes.