[Vanilla Fix] Fix incorrect damage area logic (#1707)

Fixed the issue that the widespread damage caused by detonation on the
bridge/ground cannot affect objects on the ground/bridge who are in the
opposite case.

---

- Perhaps WW wants to do some optimization, but obviously this is not
reasonable.

Author: CrimRecya

CREDITS.md

@@ -485,6 +485,7 @@ This page lists all the individual contributions to the project by their author.
   - Amphibious access vehicle
   - Fix an issue that spawned `Strafe` aircraft on aircraft carriers may not be able to return normally if aircraft carriers moved a short distance when the aircraft is landing
   - Exclusive SuperWeapon Sidebar
+  - Fix an issue that the widespread damage caused by detonation on the bridge/ground cannot affect objects on the ground/bridge who are in the opposite case
 - **Ollerus**:
   - Build limit group enhancement
   - Customizable rocker amplitude

docs/Fixed-or-Improved-Logics.md

@@ -230,6 +230,7 @@ This page describes all ingame logics that are fixed or improved in Phobos witho
 - Fixed the bug that uncontrolled scatter when elite techno attacked by aircraft or some unit try crush it.
 - Second weapon with `ElectricAssault=yes` will not unconditionally attack your building with `Overpowerable=yes`.
 - Infantry support `IsGattling=yes`.
+- Fixed the issue that the widespread damage caused by detonation on the bridge/ground cannot affect objects on the ground/bridge who are in the opposite case.
 
 ## Fixes / interactions with other extensions
 

docs/Whats-New.md

@@ -413,6 +413,7 @@ Vanilla fixes:
 - Fixed an issue where airstrike flare line drawn to target at lower elevation would clip (by Starkku)
 - Fixed the bug that uncontrolled scatter when elite techno attacked by aircraft or some unit try crush it (by NetsuNegi)
 - Second weapon with `ElectricAssault=yes` will not unconditionally attack your building with `Overpowerable=yes` (by FlyStar)
+- Fixed the issue that the widespread damage caused by detonation on the bridge/ground cannot affect objects on the ground/bridge who are in the opposite case (by CrimRecya)
 
 Phobos fixes:
 - Fixed the bug that `AllowAirstrike=no` cannot completely prevent air strikes from being launched against it (by NetsuNegi)

src/Misc/Hooks.BugFixes.cpp

@@ -2041,3 +2041,129 @@ DEFINE_HOOK(0x4D6FE1, FootClass_ElectricAssultFix2, 0x7)		// Mission_AreaGuard
 }
 
 #pragma endregion
+
+#pragma region DamageAreaItemsFix
+// Obviously, it is unreasonable for a large-scale damage like a nuke to only cause damage to units
+// located on or under the bridge that are in the same position as the damage center point
+namespace DamageAreaTemp
+{
+	const CellClass* CheckingCell = nullptr;
+	bool CheckingCellAlt = false;
+}
+// Skip useless alt check, so it will only start checking from the cell's FirstObject
+// Note: Ares hook at 0x489562(0x6) and return 0
+DEFINE_JUMP(LJMP, 0x489568, 0x489592);
+
+DEFINE_HOOK(0x4896BF, DamageArea_DamageItemsFix1, 0x6)
+{
+	enum { CheckNextCell = 0x4899BE, CheckThisObject = 0x4896DD };
+	// Record the current cell for linked list getting
+	GET(const CellClass* const, pCell, EBX);
+	DamageAreaTemp::CheckingCell = pCell;
+	// First, check the FirstObject linked list
+	auto pObject = pCell->FirstObject;
+	// Check if there are objects in the linked list
+	if (pObject)
+	{
+		// When it exists, start the vanilla processing
+		R->ESI(pObject);
+		return CheckThisObject;
+	}
+	// When it does not exist, check AltObject linked list
+	pObject = pCell->AltObject;
+	// If there is also no object in the linked list, return directly to check the next cell
+	if (!pObject)
+		return CheckNextCell;
+	// If there is an object, record the flag
+	DamageAreaTemp::CheckingCellAlt = true;
+	// Then return and continue with the original execution
+	R->ESI(pObject);
+	return CheckThisObject;
+}
+
+DEFINE_HOOK(0x4899B3, DamageArea_DamageItemsFix2, 0x5)
+{
+	enum { CheckNextCell = 0x4899BE, CheckThisObject = 0x4896DD };
+	// When there are no units in the FirstObject linked list, it will not enter this hook
+	GET(const ObjectClass*, pObject, ESI);
+	// As vanilla, first look at the next object in the linked list
+	pObject = pObject->NextObject;
+	// Check if there are still objects in the linked list
+	if (pObject)
+	{
+		// When it exists, return to continue the vanilla processing
+		R->ESI(pObject);
+		return CheckThisObject;
+	}
+	// When it does not exist, check which linked list it is currently in
+	if (DamageAreaTemp::CheckingCellAlt)
+	{
+		// If it is already in the AltObject linked list, reset the flag and return to check the next cell
+		DamageAreaTemp::CheckingCellAlt = false;
+		return CheckNextCell;
+	}
+	// If it is still in the FirstObject linked list, take the first object in the AltObject linked list and continue checking
+	pObject = DamageAreaTemp::CheckingCell->AltObject;
+	// If there is no object in the AltObject linked list, return directly to check the next cell
+	if (!pObject)
+		return CheckNextCell;
+	// If there is an object, record the flag
+	DamageAreaTemp::CheckingCellAlt = true;
+	// Then return and continue with the original execution
+	R->ESI(pObject);
+	return CheckThisObject;
+}
+
+DEFINE_HOOK(0x489BDB, DamageArea_RockerItemsFix1, 0x6)
+{
+	enum { SkipGameCode = 0x489C29 };
+	// Get cell coordinates
+	GET(const short, cellX, ESI);
+	GET(const short, cellY, EBX);
+	// Record the current cell for linked list getting
+	const auto pCell = MapClass::Instance.GetCellAt(CellStruct { cellX, cellY });
+	DamageAreaTemp::CheckingCell = pCell;
+	// First, check the FirstObject linked list
+	auto pObject = pCell->FirstObject;
+	// Check if there are objects in the linked list
+	if (pObject)
+	{
+		// When it exists, start the vanilla processing
+		R->EAX(pObject);
+		return SkipGameCode;
+	}
+	// When it does not exist, check AltObject linked list
+	pObject = pCell->AltObject;
+	// If there is an object, record the flag
+	if (pObject)
+		DamageAreaTemp::CheckingCellAlt = true;
+	// Return the original check
+	R->EAX(pObject);
+	return SkipGameCode;
+}
+
+DEFINE_HOOK(0x489E47, DamageArea_RockerItemsFix2, 0x6)
+{
+	// Prior to this, there was already pObject = pCell->FirstObject;
+	GET(const ObjectClass*, pObject, EDI);
+	// As vanilla, first look at the next object in the linked list
+	if (pObject)
+		return 0;
+	// When it does not exist, check which linked list it is currently in
+	if (DamageAreaTemp::CheckingCellAlt)
+	{
+		// If it is already in the AltObject linked list, reset the flag and return the original check
+		DamageAreaTemp::CheckingCellAlt = false;
+		return 0;
+	}
+	// If it is still in the FirstObject linked list, take the first object in the AltObject linked list and continue checking
+	pObject = DamageAreaTemp::CheckingCell->AltObject;
+	// If there is an object, record the flag
+	if (pObject)
+		DamageAreaTemp::CheckingCellAlt = true;
+	// Return the original check
+	R->EDI(pObject);
+	return 0;
+}
+
+#pragma region