[Dehardcode] Make harvesters do addtional scan after unload (#1642)

### Make harvesters do addtional scan after unload

- In vanilla, miners will remember their current location when they
reach full load and move to that location after unloading. This makes
miners to gradually move deeper into the mine and ignore the closer
minerals.
- Now you can have the miner search for the nearest mineral again after
unloading. If a closer mineral is found, the miner will go to that
location instead of the previously recorded location.

In `rulesmd.ini`:
```ini
[General]
HarvesterScanAfterUnload=false     ; boolean

[SOMEVEHICLE]
HarvesterScanAfterUnload=          ; boolean, default to [General] -> HarvesterScanAfterUnload
```

Author: TaranDahl

CREDITS.md

@@ -499,6 +499,7 @@ This page lists all the individual contributions to the project by their author.
   - Prone speed customization
   - RadarInvisible for non-enemy house
   - Allow miners do area guard
+  - Make harvesters do addtional scan after unload
 - **tyuah8**:
   - Drive/Jumpjet/Ship/Teleport locomotor did not power on when it is un-piggybacked bugfix
   - Destroyed unit leaves sensors bugfix

docs/Fixed-or-Improved-Logics.md

@@ -1440,6 +1440,20 @@ DeployingAnim.ReverseForUndeploy=true  ; boolean
 DeployingAnim.UseUnitDrawer=true       ; boolean
 ```
 
+### Make harvesters do addtional scan after unload
+
+- In vanilla, miners will remember their current location when they reach full load and move to that location after unloading. This makes miners to gradually move deeper into the mine and ignore the closer minerals.
+- Now you can have the miner search for the nearest mineral again after unloading. If a closer mineral is found, the miner will go to that location instead of the previously recorded location.
+
+In `rulesmd.ini`:
+```ini
+[General]
+HarvesterScanAfterUnload=false     ; boolean
+
+[SOMEVEHICLE]
+HarvesterScanAfterUnload=          ; boolean, default to [General] -> HarvesterScanAfterUnload
+```
+
 ### Preserve Iron Curtain / Force Shield status on type conversion
 
 ![image](_static/images/preserve-ic.gif)

docs/Whats-New.md

@@ -371,6 +371,7 @@ New:
 - Aggressive attack move mission (by CrimRecya)
 - Amphibious access vehicle (by CrimRecya)
 - Allow miners do area guard (by TaranDahl)
+- Make harvesters do addtional scan after unload (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

@@ -262,6 +262,8 @@ void RulesExt::ExtData::LoadBeforeTypeData(RulesClass* pThis, CCINIClass* pINI)
 
   	this->DamagedSpeed.Read(exINI, GameStrings::General, "DamagedSpeed");
 
+	this->HarvesterScanAfterUnload.Read(exINI, GameStrings::General, "HarvesterScanAfterUnload");
+
 	// Section AITargetTypes
 	int itemsCount = pINI->GetKeyCount("AITargetTypes");
 	for (int i = 0; i < itemsCount; ++i)
@@ -482,6 +484,7 @@ void RulesExt::ExtData::Serialize(T& Stm)
 		.Process(this->ProneSpeed_Crawls)
 		.Process(this->ProneSpeed_NoCrawls)
     	.Process(this->DamagedSpeed)
+		.Process(this->HarvesterScanAfterUnload)
 		;
 }
 

src/Ext/Rules/Body.h

@@ -217,6 +217,8 @@ class RulesExt
 
     	Valueable<double> DamagedSpeed;
 
+		Valueable<bool> HarvesterScanAfterUnload;
+
 		ExtData(RulesClass* OwnerObject) : Extension<RulesClass>(OwnerObject)
 			, Storage_TiberiumIndex { -1 }
 			, HarvesterDumpAmount { 0.0f }
@@ -379,6 +381,8 @@ class RulesExt
 			, ProneSpeed_NoCrawls { 1.5 }
 
       		, DamagedSpeed { 0.75 }
+			
+			, HarvesterScanAfterUnload { false }
 		{ }
 
 		virtual ~ExtData() = default;

src/Ext/TechnoType/Body.cpp

@@ -550,6 +550,7 @@ void TechnoTypeExt::ExtData::LoadFromINIFile(CCINIClass* const pINI)
 	this->Overload_ParticleSysCount.Read(exINI, pSection, "Overload.ParticleSysCount");
 
 	this->Harvester_CanGuardArea.Read(exINI, pSection, "Harvester.CanGuardArea");
+	this->HarvesterScanAfterUnload.Read(exINI, pSection, "HarvesterScanAfterUnload");
 
 	// Ares 0.2
 	this->RadarJamRadius.Read(exINI, pSection, "RadarJamRadius");
@@ -1018,8 +1019,9 @@ void TechnoTypeExt::ExtData::Serialize(T& Stm)
 		.Process(this->Overload_DeathSound)
 		.Process(this->Overload_ParticleSys)
 		.Process(this->Overload_ParticleSysCount)
-		
+
 		.Process(this->Harvester_CanGuardArea)
+		.Process(this->HarvesterScanAfterUnload)
 		;
 }
 void TechnoTypeExt::ExtData::LoadFromStream(PhobosStreamReader& Stm)

src/Ext/TechnoType/Body.h

@@ -345,6 +345,7 @@ class TechnoTypeExt
 		Valueable<int> Overload_ParticleSysCount;
 
 		Valueable<bool> Harvester_CanGuardArea;
+		Nullable<bool> HarvesterScanAfterUnload;
 
 		ExtData(TechnoTypeClass* OwnerObject) : Extension<TechnoTypeClass>(OwnerObject)
 			, HealthBar_Hide { false }
@@ -643,8 +644,9 @@ class TechnoTypeExt
 			, Overload_DeathSound {}
 			, Overload_ParticleSys {}
 			, Overload_ParticleSysCount { 5 }
-			
+
 			, Harvester_CanGuardArea { false }
+			, HarvesterScanAfterUnload {}
 		{ }
 
 		virtual ~ExtData() = default;

src/Ext/Unit/Hooks.Harvester.cpp

@@ -30,4 +30,34 @@ DEFINE_HOOK(0x4D6D34, FootClass_MissionAreaGuard_Miner, 0x5)
 	auto const pTypeExt = TechnoTypeExt::ExtMap.Find(pThis->GetTechnoType());
 
 	return pTypeExt->Harvester_CanGuardArea && pThis->Owner->IsControlledByHuman() ? GoGuardArea : 0;
-}
+}
+
+#pragma region HarvesterScanAfterUnload
+
+DEFINE_HOOK(0x73E730, UnitClass_MissionHarvest_HarvesterScanAfterUnload, 0x5)
+{
+	GET(UnitClass* const, pThis, EBP);
+	GET(AbstractClass* const, pFocus, EAX);
+
+	// Focus is set when the harvester is fully loaded and go home.
+	if (pFocus && TechnoTypeExt::ExtMap.Find(pThis->Type)->HarvesterScanAfterUnload.Get(RulesExt::Global()->HarvesterScanAfterUnload))
+	{
+		auto cellBuffer = CellStruct::Empty;
+		const auto pCellStru = pThis->ScanForTiberium(&cellBuffer, RulesClass::Instance->TiberiumLongScan / Unsorted::LeptonsPerCell, 0);
+
+		if (*pCellStru != CellStruct::Empty)
+		{
+			const auto pCell = MapClass::Instance.TryGetCellAt(*pCellStru);
+			const auto distFromTiberium = pCell ? pThis->DistanceFrom(pCell) : -1;
+			const auto distFromFocus = pThis->DistanceFrom(pFocus);
+
+			// Check if pCell is better than focus.
+			if (distFromTiberium > 0 && distFromTiberium < distFromFocus)
+				R->EAX(pCell);
+		}
+	}
+
+	return 0;
+}
+
+#pragma endregion