Customize several behavior of mission area guard

CREDITS.md

@@ -689,6 +689,7 @@ This page lists all the individual contributions to the project by their author.
   - Fixed an issue that retaliation will make the unit keep switching among multiple targets with the same amount of threat
   - Fix an issue where units recruited by a team with `AreTeamMembersRecruitable=false` cannot be recruited even if they have been liberated by that team
   - Global default value for `DefaultToGuardArea`
+  - Customize several behavior of mission area guard
 - **solar-III (凤九歌)**
   - Target scanning delay customization (documentation)
   - Skip target scanning function calling for unarmed technos (documentation)

docs/Fixed-or-Improved-Logics.md

@@ -1560,6 +1560,27 @@ FallingDownDamage=              ; integer / percentage
 FallingDownDamage.Water=        ; integer / percentage
 ```
 
+### Customize several behavior of mission area guard
+
+- In vanilla, technos in area guard mission will use the focus as the center of targeting and stray.
+  - Now you can change the center to itself by using `AreaGuard.UseSelfAsCenter=true`. (For stray, what is checked is the distance between the techno and the current target)
+- In vanilla, technos in area guard mission will do targeting in an extended range (roughly 2 times of the guard range).
+  - Now you can change the range to the guard range by using `AreaGuard.TargetingInRange=true`.
+- In vanilla, technos in area guard mission will not stray unless it has no destination.
+  - Now you can change the behavior by using `AreaGuard.StrayIgnoreDestination=true`.
+
+In `rulesmd.ini`:
+```ini
+[General]
+AreaGuard.UseSelfAsCenter=         ; boolean
+AreaGuard.TargetingInRange=        ; boolean
+AreaGuard.StrayIgnoreDestination=  ; boolean
+```
+
+```{note}
+In vanilla, if `GuardRange` is not set, then the guard range will be automatically deduced based on the weapon range.
+```
+
 ### Damaged speed customization
 
 - In vanilla, units using drive/ship loco will has hardcoded speed multiplier when damaged. Now you can customize it.

docs/Whats-New.md

@@ -534,6 +534,7 @@ New:
 - [Customizable paradropped unit missions](Fixed-or-Improved-Logics.md#customizable-paradrop-missions) (by Starkku)
 - Option to scale `PowerSurplus` setting if enabled to current power drain with `PowerSurplus.ScaleToDrainAmount` (by Starkku)
 - Global default value for `DefaultToGuardArea` (by TaranDahl)
+- [Customize several behavior of mission area guard](Fixed-or-Improved-Logics.md#customize-several-behavior-of-mission-area-guard) (by TaranDahl)
 
 Vanilla fixes:
 - Fixed sidebar not updating queued unit numbers when adding or removing units when the production is on hold (by CrimRecya)

src/Ext/Rules/Body.cpp

@@ -362,6 +362,10 @@ void RulesExt::ExtData::LoadBeforeTypeData(RulesClass* pThis, CCINIClass* pINI)
 	this->ParadropMission.Read(exINI, GameStrings::General, "ParadropMission");
 	this->AIParadropMission.Read(exINI, GameStrings::General, "AIParadropMission");
 
+	this->AreaGuard_UseSelfAsCenter.Read(exINI, GameStrings::General, "AreaGuard.UseSelfAsCenter");
+	this->AreaGuard_TargetingInRange.Read(exINI, GameStrings::General, "AreaGuard.TargetingInRange");
+	this->AreaGuard_StrayIgnoreDestination.Read(exINI, GameStrings::General, "AreaGuard.StrayIgnoreDestination");
+
 	// Section AITargetTypes
 	int itemsCount = pINI->GetKeyCount("AITargetTypes");
 	for (int i = 0; i < itemsCount; ++i)
@@ -660,6 +664,9 @@ void RulesExt::ExtData::Serialize(T& Stm)
 		.Process(this->ParadropMission)
 		.Process(this->AIParadropMission)
 		.Process(this->DefaultToGuardArea)
+		.Process(this->AreaGuard_UseSelfAsCenter)
+		.Process(this->AreaGuard_TargetingInRange)
+		.Process(this->AreaGuard_StrayIgnoreDestination)
 		;
 }
 

src/Ext/Rules/Body.h

@@ -1,4 +1,4 @@
-#pragma once
+#pragma once
 
 #include <RulesClass.h>
 #include <Utilities/Container.h>
@@ -311,6 +311,9 @@ class RulesExt
 		Valueable<Mission> AIParadropMission;
 
 		Valueable<bool> DefaultToGuardArea;
+		Valueable<bool> AreaGuard_UseSelfAsCenter;
+		Valueable<bool> AreaGuard_TargetingInRange;
+		Valueable<bool> AreaGuard_StrayIgnoreDestination;
 
 		ExtData(RulesClass* OwnerObject) : Extension<RulesClass>(OwnerObject)
 			, Storage_TiberiumIndex { -1 }
@@ -566,6 +569,9 @@ class RulesExt
 			, AIParadropMission { Mission::Hunt }
 
 			, DefaultToGuardArea { false }
+			, AreaGuard_UseSelfAsCenter { false }
+			, AreaGuard_TargetingInRange { false }
+			, AreaGuard_StrayIgnoreDestination { false }
 		{ }
 
 		virtual ~ExtData() = default;

src/Ext/Techno/Hooks.Targeting.cpp

@@ -69,3 +69,36 @@ DEFINE_HOOK(0x6F7CE2, TechnoClass_CanAutoTargetObject_IronCurtain, 0x6)
 
 	return 0;
 }
+
+#pragma region AreaGuard
+
+DEFINE_HOOK(0x4D6E9F, FootClass_MissionAreaGuard_UseSelfAsCenter, 0x6)
+{
+	enum { CheckDist = 0x4D6EAF, ResetTarget = 0x4D6ED1 };
+
+	GET(FootClass*, pThis, ESI);
+
+	if (!RulesExt::Global()->AreaGuard_StrayIgnoreDestination && pThis->Destination)
+		return ResetTarget;
+
+	R->EAX(pThis->DistanceFrom(RulesExt::Global()->AreaGuard_UseSelfAsCenter ? pThis->Target : pThis->ArchiveTarget));
+	return CheckDist;
+}
+
+namespace AreaGuard_UseSelfAsCenterContext
+{
+	CoordStruct crd;
+}
+
+DEFINE_HOOK(0x4D6EFD, FootClass_MissionAreaGuard_Extend, 0x6)
+{
+	enum { SkipGameCode = 0x4D6F03 };
+
+	GET(FootClass*, pThis, ESI);
+	AreaGuard_UseSelfAsCenterContext::crd = (RulesExt::Global()->AreaGuard_UseSelfAsCenter ? pThis : pThis->ArchiveTarget)->GetCoords();
+	R->EAX(&AreaGuard_UseSelfAsCenterContext::crd);
+	R->Stack(0, RulesExt::Global()->AreaGuard_TargetingInRange ? ThreatType::Range : ThreatType::Area);
+	return 0;
+}
+
+#pragma endregion