Allow Laser drawing position update

CREDITS.md

@@ -695,6 +695,7 @@ This page lists all the individual contributions to the project by their author.
   - Customize the step limit of the credits indicator
   - Disable the credits indicator smooth transition
   - Add `selling`, `undeploying` and `harvesting` conditions to `DiscardOn`
+  - Allow Laser drawing position update
 - **Ollerus**:
   - Build limit group enhancement
   - Customizable rocker amplitude

docs/New-or-Enhanced-Logics.md

@@ -3081,6 +3081,36 @@ UnlimboDetonate.KeepSelected=true      ; boolean
 
 ## Weapons
 
+### Allow Laser drawing position update
+
+- Now you can define via `LaserPositionUpdate` whether the endpoints of a laser drawing are updated during its duration.
+  - `None`: No update.
+  - `Firer`: The start point follows the firer's FLH; if the firer dies, the update stops.
+    - Since the FLH of `DiskLaser` actually determines the center of the ring, in this scenario, during the update process, the direction of the line connecting the beam's starting point to the center is fixed relative to the ground and the distance is constant - that is, the starting point will still remain on the ring.
+  - `Target`: The end point follows the target; if the target object dies, the update stops.
+  - `All`: Equivalent to specifying both `Firer` and `Target`.
+- `LaserPositionUpdate.StopOnFirerConvert` determines whether the laser source stops updating when the firer transforms. If set to false (default), the laser will continue to update using the transformed unit's corresponding parameters.
+
+```{note}
+For a sub-weapon created by `ShrapnelWeapon` or `AirburstWeapon`, its start point is the position where the parent weapon detonates, not the firer's FLH.
+- If `Firer` is set, it will be treated as `None`.
+- If `All` is set, it will be treated as `Target`.
+```
+
+In `rulesmd.ini`:
+```ini
+[AudioVisual]
+LaserPositionUpdate.StopOnFirerConvert=false ; boolean
+
+[SOMEWEAPON]                                 ; WeaponType with IsLaser=yes or DiskLaser=yes
+LaserPositionUpdate=none                     ; Position Follow Enumeration (none|firer|target|all)
+LaserPositionUpdate.StopOnFirerConvert=false ; boolean, default to [AudioVisual] -> LaserPositionUpdate.StopOnFirerConvert
+```
+
+```{warning}
+If the weapon sets this logic to a non-`None` value while also using other logics that change the drawing position, such as `FlakScatter` and `VisualScatter`, then after initially drawing the laser according to those other logics, the drawing position will be forced to change due to the update rules.
+```
+
 ### AreaFire target customization
 
 - You can now specify how AreaFire weapon picks its target. By default it targets the base cell the firer is currently on, but this can now be changed to fire on the firer itself or at a random cell within the radius of the weapon's `Range` by setting `AreaFire.Target` to `self` or `random` respectively.

docs/Whats-New.md

@@ -606,6 +606,7 @@ HideShakeEffects=false           ; boolean
 - [Customize the step limit of the credits indicator](User-Interface.md#customize-the-step-limit-of-the-credits-indicator) (by Noble_Fish)
 - [Disable the credits indicator smooth transition](User-Interface.md#disable-the-credits-indicator-smooth-transition) (by Noble_Fish)
 - Add `selling`, `undeploying` and `harvesting` conditions to `DiscardOn` (by Noble_Fish)
+- [Allow Laser drawing position update](New-or-Enhanced-Logics.md#allow-laser-drawing-position-update) (by Noble_Fish)
 
 #### Vanilla fixes:
 - Fixed sidebar not updating queued unit numbers when adding or removing units when the production is on hold (by CrimRecya)

src/Ext/Bullet/Body.cpp

@@ -7,6 +7,11 @@
 #include <Ext/EBolt/Body.h>
 #include <New/Entity/LaserTrailClass.h>
 
+namespace LaserRT
+{
+	void SetLaserTrackingData(LaserDrawClass* pLaser, TechnoClass* pShooter, AbstractClass* pTarget, int weaponIdx, PositionFollow mode, bool ignoreShooter);
+}
+
 BulletExt::ExtContainer BulletExt::ExtMap;
 
 void BulletExt::ExtData::InterceptBullet(TechnoClass* pSource, BulletClass* pInterceptor)
@@ -204,10 +209,12 @@ inline void BulletExt::SimulatedFiringLaser(BulletClass* pBullet, HouseClass* pH
 
 	const auto pWeaponExt = WeaponTypeExt::ExtMap.Find(pWeapon);
 
+	LaserDrawClass* pLaser = nullptr;
+
 	if (pWeapon->IsHouseColor || pWeaponExt->Laser_IsSingleColor)
 	{
 		const auto black = ColorStruct { 0, 0, 0 };
-		const auto pLaser = GameCreate<LaserDrawClass>(pBullet->SourceCoords, BulletExt::GetTargetCoordsForFiring(pBullet),
+		pLaser = GameCreate<LaserDrawClass>(pBullet->SourceCoords, BulletExt::GetTargetCoordsForFiring(pBullet),
 			((pWeapon->IsHouseColor && pHouse) ? pHouse->LaserColor : pWeapon->LaserInnerColor), black, black, pWeapon->LaserDuration);
 
 		pLaser->IsHouseColor = true;
@@ -216,13 +223,34 @@ inline void BulletExt::SimulatedFiringLaser(BulletClass* pBullet, HouseClass* pH
 	}
 	else
 	{
-		const auto pLaser = GameCreate<LaserDrawClass>(pBullet->SourceCoords, BulletExt::GetTargetCoordsForFiring(pBullet),
+		pLaser = GameCreate<LaserDrawClass>(pBullet->SourceCoords, BulletExt::GetTargetCoordsForFiring(pBullet),
 			pWeapon->LaserInnerColor, pWeapon->LaserOuterColor, pWeapon->LaserOuterSpread, pWeapon->LaserDuration);
 
 		pLaser->IsHouseColor = false;
 		pLaser->Thickness = 3;
 		pLaser->IsSupported = false;
 	}
+
+	// LaserPositionUpdate
+	if (pLaser)
+	{
+		auto mode = pWeaponExt->LaserPositionUpdate;
+		const bool isSplit = BulletExt::ExtMap.Find(pBullet)->IsSplitFromAirburst;
+
+		if (isSplit)
+		{
+			if (mode == PositionFollow::Firer)
+				mode = PositionFollow::None;
+			else if (mode == PositionFollow::All)
+				mode = PositionFollow::Target;
+		}
+
+		if (mode != PositionFollow::None)
+		{
+			auto const pTarget = abstract_cast<ObjectClass*>(pBullet->Target);
+			LaserRT::SetLaserTrackingData(pLaser, pBullet->Owner, pTarget, 0, mode, isSplit);
+		}
+	}
 }
 
 // Make sure pBullet and pBullet->WeaponType is not empty before call

src/Ext/Bullet/Body.h

@@ -35,6 +35,7 @@ class BulletExt
 		int ParabombFallRate;
 		bool IsInstantDetonation;
 		double FirepowerMult;
+		bool IsSplitFromAirburst = false;
 
 		TrajectoryPointer Trajectory;
 

src/Ext/Bullet/Hooks.DetonateLogics.cpp

@@ -901,6 +901,7 @@ DEFINE_HOOK(0x469EC0, BulletClass_Logics_AirburstWeapon, 0x6)
 					}
 
 					BulletExt::ExtMap.Find(pBullet)->FirepowerMult = pBulletExt->FirepowerMult;
+					BulletExt::ExtMap.Find(pBullet)->IsSplitFromAirburst = true;
 					BulletExt::SimulatedFiringUnlimbo(pBullet, pOwner, pWeapon, coords, headToTarget, radialFire);
 					BulletExt::SimulatedFiringEffects(pBullet, pOwner, nullptr, useFiringEffects, true);
 				}

src/Ext/Rules/Body.cpp

@@ -197,6 +197,7 @@ void RulesExt::ExtData::LoadBeforeTypeData(RulesClass* pThis, CCINIClass* pINI)
 	this->AirstrikeLineColor.Read(exINI, GameStrings::AudioVisual, "AirstrikeLineColor");
 	this->AirstrikeLineZAdjust.Read(exINI, GameStrings::AudioVisual, "AirstrikeLineZAdjust");
 
+	this->LaserPositionUpdate_StopOnFirerConvert.Read(exINI, GameStrings::AudioVisual, "LaserPositionUpdate.StopOnFirerConvert");
 	this->LaserZAdjust.Read(exINI, GameStrings::AudioVisual, "LaserZAdjust");
 	this->EBoltZAdjust.Read(exINI, GameStrings::AudioVisual, "EBoltZAdjust");
 	this->EBoltZAdjust_ClampInitialDepthForBuilding.Read(exINI, GameStrings::AudioVisual, "EBoltZAdjust.ClampInitialDepthForBuilding");
@@ -617,6 +618,7 @@ void RulesExt::ExtData::Serialize(T& Stm)
 		.Process(this->ColorAddUse8BitRGB)
 		.Process(this->AirstrikeLineColor)
 		.Process(this->AirstrikeLineZAdjust)
+		.Process(this->LaserPositionUpdate_StopOnFirerConvert)
 		.Process(this->LaserZAdjust)
 		.Process(this->EBoltZAdjust)
 		.Process(this->EBoltZAdjust_ClampInitialDepthForBuilding)

src/Ext/Rules/Body.h

@@ -144,6 +144,7 @@ class RulesExt
 		Valueable<ColorStruct> AirstrikeLineColor;
 		Valueable<int> AirstrikeLineZAdjust;
 
+		Valueable<bool> LaserPositionUpdate_StopOnFirerConvert;
 		Valueable<int> LaserZAdjust;
 		Valueable<int> EBoltZAdjust;
 		Valueable<bool> EBoltZAdjust_ClampInitialDepthForBuilding;
@@ -486,6 +487,7 @@ class RulesExt
 			, ColorAddUse8BitRGB { false }
 			, AirstrikeLineColor { { 255, 0, 0 } }
 			, AirstrikeLineZAdjust { 0 }
+			, LaserPositionUpdate_StopOnFirerConvert { false }
 			, LaserZAdjust { 0 }
 			, EBoltZAdjust { 0 }
 			, EBoltZAdjust_ClampInitialDepthForBuilding { true }

src/Ext/WeaponType/Body.cpp

@@ -117,6 +117,8 @@ void WeaponTypeExt::ExtData::LoadFromINIFile(CCINIClass* const pINI)
 	this->AreaFire_Target.Read(exINI, pSection, "AreaFire.Target");
 	this->FeedbackWeapon.Read<true>(exINI, pSection, "FeedbackWeapon");
 	this->Laser_IsSingleColor.Read(exINI, pSection, "IsSingleColor");
+	this->LaserPositionUpdate.Read(exINI, pSection, "LaserPositionUpdate");
+	this->LaserPositionUpdate_StopOnFirerConvert.Read(exINI, pSection, "LaserPositionUpdate.StopOnFirerConvert");
 	this->LaserZAdjust.Read(exINI, pSection, "LaserZAdjust");
 	this->EBoltZAdjust.Read(exINI, pSection, "EBoltZAdjust");
 	this->EBoltZAdjust_ClampInitialDepthForBuilding.Read(exINI, pSection, "EBoltZAdjust.ClampInitialDepthForBuilding");
@@ -244,6 +246,8 @@ void WeaponTypeExt::ExtData::Serialize(T& Stm)
 		.Process(this->AreaFire_Target)
 		.Process(this->FeedbackWeapon)
 		.Process(this->Laser_IsSingleColor)
+		.Process(this->LaserPositionUpdate)
+		.Process(this->LaserPositionUpdate_StopOnFirerConvert)
 		.Process(this->LaserZAdjust)
 		.Process(this->EBoltZAdjust)
 		.Process(this->EBoltZAdjust_ClampInitialDepthForBuilding)

src/Ext/WeaponType/Body.h

@@ -45,6 +45,8 @@ class WeaponTypeExt
 		Valueable<AreaFireTarget> AreaFire_Target;
 		Valueable<WeaponTypeClass*> FeedbackWeapon;
 		Valueable<bool> Laser_IsSingleColor;
+		Valueable<PositionFollow> LaserPositionUpdate;
+		Nullable<bool> LaserPositionUpdate_StopOnFirerConvert;
 		Nullable<int> LaserZAdjust;
 		Nullable<int> EBoltZAdjust;
 		Nullable<bool> EBoltZAdjust_ClampInitialDepthForBuilding;
@@ -136,6 +138,8 @@ class WeaponTypeExt
 			, AreaFire_Target { AreaFireTarget::Base }
 			, FeedbackWeapon {}
 			, Laser_IsSingleColor { false }
+			, LaserPositionUpdate { PositionFollow::None }
+			, LaserPositionUpdate_StopOnFirerConvert {}
 			, LaserZAdjust {}
 			, EBoltZAdjust {}
 			, EBoltZAdjust_ClampInitialDepthForBuilding {}
@@ -235,4 +239,7 @@ class WeaponTypeExt
 	static int GetRangeWithModifiers(WeaponTypeClass* pThis, TechnoClass* pFirer);
 	static int GetRangeWithModifiers(WeaponTypeClass* pThis, TechnoClass* pFirer, int range);
 	static int GetTechnoKeepRange(WeaponTypeClass* pThis, TechnoClass* pFirer, bool isMinimum);
+
+	// Misc/Hooks.LaserDraw.cpp
+	static void LaserTrackingPointerExpired(void* ptr, bool removed);
 };