Implement open-topped building support and fix building self-attack issue

CREDITS.md

@@ -51,6 +51,8 @@ This page lists all the individual contributions to the project by their author.
   - Warhead activation target health thresholds
   - MP saves support for quicksave command and savegame trigger action
   - Ported XNA CnCNet Client MP save handling
+  - Open-topped buildings
+  - Building unload self-attack fix
 - **Uranusian (Thrifinesma)**:
   - Mind Control enhancement
   - Custom warhead splash list

docs/Fixed-or-Improved-Logics.md

@@ -262,6 +262,8 @@ This page describes all ingame logics that are fixed or improved in Phobos witho
 - `DeployingAnim` using unit drawer now also tint accordingly with the unit.
 - Fixed an issue that jumpjets in air can not correctly spawn missiles.
 - Fixed an issue that the currently hovered planning node not update up-to-date, such as using hotkeys to select technos.
+- Fixed `OpenTopped` to work with buildings.
+- Fixed buildings giving an order to attack self when unloading (manifested with opentopped buildings and garrisons leaving buildings sometimes).
 
 ## Fixes / interactions with other extensions
 

docs/Whats-New.md

@@ -473,6 +473,8 @@ Vanilla fixes:
 - `DeployingAnim` using unit drawer now also tint accordingly with the unit (by Starkku)
 - Jumpjets in air now can correctly spawn missiles (by TaranDahl)
 - Fixed an issue that the currently hovered planning node not update up-to-date, such as using hotkeys to select technos (by CrimRecya)
+- Fixed `OpenTopped` to work with buildings (by Kerbiter)
+- Fixed buildings giving an order to attack self when unloading (manifested with opentopped buildings and garrisons leaving buildings sometimes) (by Kerbiter)
 
 Phobos fixes:
 - Fixed the bug that `AllowAirstrike=no` cannot completely prevent air strikes from being launched against it (by NetsuNegi)

src/Ext/Techno/Body.Update.cpp

@@ -1130,6 +1130,7 @@ void TechnoExt::ExtData::UpdateTypeData_Foot()
 
 	// Update open topped state of potential passengers if transport's OpenTopped value changes.
 	// OpenTopped does not work properly with buildings to begin with which is why this is here rather than in the Techno update one.
+	// TODO move to non-foot since we now have proper building open-topped support
 	if (pThis->Passengers.NumPassengers > 0)
 	{
 		const bool toOpenTopped = pCurrentType->OpenTopped;

src/Misc/Hooks.BugFixes.cpp

@@ -2657,3 +2657,76 @@ DEFINE_HOOK(0x741A66, UnitClass_SetDestination_JJVehFix, 0x5)
 }
 
 #pragma endregion
+
+#pragma region OpenTopped on buildings
+
+DEFINE_HOOK(0x51A320, InfantryClass_PerCellProcess_SubmitToOpenToppedOnBuildingEnter, 0x7)
+{
+	GET(BuildingClass* const, pBuilding, EDI);
+	GET(InfantryClass* const, pThis, ESI);
+
+	if (pBuilding->Type->OpenTopped)
+		pBuilding->EnteredOpenTopped(pThis);
+
+	// there's no opentopped infantry... yet :P
+	if (pThis->Type->OpenTopped)
+		pThis->SetTargetForPassengers(nullptr);
+
+	// where's Multfinite's cncnet5 cli... erm, I mean, fixup of the stolen relative address instructions???
+	// return 0;
+
+	R->EAX(pBuilding->IsAbsorbAllowed());
+	return 0x51A327;
+}
+
+DEFINE_HOOK(0x73A2F4, UnitClass_PerCellProcess_SubmitToOpenToppedOnBuildingEnter, 0x6)
+{
+	GET(UnitClass* const, pThis, EBP);
+	GET(BuildingClass* const, pBuilding, EBX);
+
+	if (pBuilding->Type->OpenTopped)
+		pBuilding->EnteredOpenTopped(pThis);
+
+	if (pThis->Type->OpenTopped)
+		pThis->SetTargetForPassengers(nullptr);
+
+	return 0;
+}
+
+DEFINE_HOOK(0x44DBA9, BuildingClass_MissionUnload_DisableOpenToppedForUnloading, 0x6)
+{
+	GET(BuildingClass* const, pThis, EBP);
+	GET(FootClass* const, pFoot, ESI);
+
+	if (pThis->Type->OpenTopped)
+		pThis->ExitedOpenTopped(pFoot);
+
+	if (pThis->Type->OpenTopped && pFoot->Owner != pThis->Owner)
+		pFoot->SetTarget(nullptr);
+
+	return 0;
+}
+
+// misleading WW name, Drop_Debris also handles survivors
+DEFINE_HOOK(0x442D97, BuildingClass_DropDebris_DisableOpenTopped, 0x6)
+{
+	GET(BuildingClass* const, pThis, ECX);
+
+	if (pThis->Type->OpenTopped)
+		pThis->MarkPassengersAsExited();
+
+	return 0;
+}
+
+#pragma endregion
+
+// previously the building was given as a target for the unload order, unlike unit unload order which uses null target
+DEFINE_HOOK_AGAIN(0x443557, BuildingClass_ActiveClickWith_NullTargetForUnload, 0x0)
+DEFINE_HOOK(0x443534, BuildingClass_ActiveClickWith_NullTargetForUnload, 0x0)
+{
+	GET(BuildingClass* const, pThis, EBX);
+
+	R->EAX(pThis->ClickedMission(Mission::Unload, nullptr, nullptr, nullptr));
+
+	return R->Origin() + 17;
+}