Extended LineAttack() with offsets and new flags

Added forward and side offsets for LineAttack() function
Added absolute offset and absolute position flags for LineAttack() function

src/p_local.h

@@ -324,15 +324,17 @@ enum	// P_AimLineAttack flags
 enum	// P_LineAttack flags
 {
 	LAF_ISMELEEATTACK = 1,
-	LAF_NORANDOMPUFFZ = 2,
+	LAF_NORANDOMPUFFZ = 1 << 1,
-	LAF_NOIMPACTDECAL = 4,
+	LAF_NOIMPACTDECAL = 1 << 2,
-	LAF_NOINTERACT =	8,
+	LAF_NOINTERACT =    1 << 3,
-	LAF_TARGETISSOURCE = 16,
+	LAF_TARGETISSOURCE= 1 << 4,
-	LAF_OVERRIDEZ =		32,
+	LAF_OVERRIDEZ =     1 << 5,
+	LAF_ABSOFFSET =     1 << 6,
+	LAF_ABSPOSITION =   1 << 7,
 };
 
-AActor *P_LineAttack(AActor *t1, DAngle angle, double distance, DAngle pitch, int damage, FName damageType, PClassActor *pufftype, int flags = 0, FTranslatedLineTarget *victim = NULL, int *actualdamage = NULL, double sz = 0.0);
+AActor *P_LineAttack(AActor *t1, DAngle angle, double distance, DAngle pitch, int damage, FName damageType, PClassActor *pufftype, int flags = 0, FTranslatedLineTarget *victim = NULL, int *actualdamage = NULL, double sz = 0.0, double offsetforward = 0.0, double offsetside = 0.0);
-AActor *P_LineAttack(AActor *t1, DAngle angle, double distance, DAngle pitch, int damage, FName damageType, FName pufftype, int flags = 0, FTranslatedLineTarget *victim = NULL, int *actualdamage = NULL, double sz = 0.0);
+AActor *P_LineAttack(AActor *t1, DAngle angle, double distance, DAngle pitch, int damage, FName damageType, FName pufftype, int flags = 0, FTranslatedLineTarget *victim = NULL, int *actualdamage = NULL, double sz = 0.0, double offsetforward = 0.0, double offsetside = 0.0);
 
 void	P_TraceBleed(int damage, const DVector3 &pos, AActor *target, DAngle angle, DAngle pitch);
 void	P_TraceBleed(int damage, AActor *target, DAngle angle, DAngle pitch);

src/p_map.cpp

@@ -4395,7 +4395,8 @@ static ETraceStatus CheckForActor(FTraceResults &res, void *userdata)
 //==========================================================================
 
 AActor *P_LineAttack(AActor *t1, DAngle angle, double distance,
-	DAngle pitch, int damage, FName damageType, PClassActor *pufftype, int flags, FTranslatedLineTarget*victim, int *actualdamage, double sz)
+	DAngle pitch, int damage, FName damageType, PClassActor *pufftype, int flags, FTranslatedLineTarget*victim, int *actualdamage, 
+	double sz, double offsetforward, double offsetside)
 {
 	bool nointeract = !!(flags & LAF_NOINTERACT);
 	DVector3 direction;
@@ -4496,7 +4497,34 @@ AActor *P_LineAttack(AActor *t1, DAngle angle, double distance,
 	if (nointeract || (puffDefaults && puffDefaults->flags6 & MF6_NOTRIGGER)) tflags = TRACE_NoSky;
 	else tflags = TRACE_NoSky | TRACE_Impact;
 
-	if (!Trace(t1->PosAtZ(shootz), t1->Sector, direction, distance, MF_SHOOTABLE, 
+	// [MC] Check the flags and set the position according to what is desired.
+	// LAF_ABSPOSITION: Treat the offset parameters as direct coordinates.
+	// LAF_ABSOFFSET: Ignore the angle.
+
+	DVector3 tempos;
+
+	if (flags & LAF_ABSPOSITION)
+	{
+		tempos = DVector3(offsetforward, offsetside, sz);
+	}
+	else if (flags & LAF_ABSOFFSET)
+	{
+		tempos = t1->Vec2OffsetZ(offsetforward, offsetside, shootz);
+	}
+	else if (0.0 == offsetforward && 0.0 == offsetside)
+	{
+		// Default case so exact comparison is enough
+		tempos = t1->PosAtZ(shootz);
+	}
+	else
+	{
+		const double s = angle.Sin();
+		const double c = angle.Cos();
+		tempos = t1->Vec2OffsetZ(offsetforward * c + offsetside * s, offsetforward * s - offsetside * c, shootz);
+	}
+
+	// Perform the trace.
+	if (!Trace(tempos, t1->Sector, direction, distance, MF_SHOOTABLE, 
 		ML_BLOCKEVERYTHING | ML_BLOCKHITSCAN, t1, trace, tflags, CheckForActor, &TData))
 	{ // hit nothing
 		if (!nointeract && puffDefaults && puffDefaults->ActiveSound)
@@ -4702,7 +4730,8 @@ AActor *P_LineAttack(AActor *t1, DAngle angle, double distance,
 }
 
 AActor *P_LineAttack(AActor *t1, DAngle angle, double distance,
-	DAngle pitch, int damage, FName damageType, FName pufftype, int flags, FTranslatedLineTarget *victim, int *actualdamage, double sz)
+	DAngle pitch, int damage, FName damageType, FName pufftype, int flags, FTranslatedLineTarget *victim, int *actualdamage, 
+	double sz, double offsetforward, double offsetside)
 {
 	PClassActor *type = PClass::FindActor(pufftype);
 	if (type == NULL)
@@ -4716,7 +4745,7 @@ AActor *P_LineAttack(AActor *t1, DAngle angle, double distance,
 	}
 	else
 	{
-		return P_LineAttack(t1, angle, distance, pitch, damage, damageType, type, flags, victim, actualdamage, sz);
+		return P_LineAttack(t1, angle, distance, pitch, damage, damageType, type, flags, victim, actualdamage, sz, offsetforward, offsetside);
 	}
 }
 
@@ -4732,10 +4761,12 @@ DEFINE_ACTION_FUNCTION(AActor, LineAttack)
 	PARAM_INT_DEF(flags);
 	PARAM_POINTER_DEF(victim, FTranslatedLineTarget);
 	PARAM_FLOAT_DEF(offsetz);
+	PARAM_FLOAT_DEF(offsetforward);
+	PARAM_FLOAT_DEF(offsetside);
 
 	int acdmg;
 	if (puffType == nullptr) puffType = PClass::FindActor("BulletPuff");	// P_LineAttack does not work without a puff to take info from.
-	auto puff = P_LineAttack(self, angle, distance, pitch, damage, damageType, puffType, flags, victim, &acdmg, offsetz);
+	auto puff = P_LineAttack(self, angle, distance, pitch, damage, damageType, puffType, flags, victim, &acdmg, offsetz, offsetforward, offsetside);
 	if (numret > 0) ret[0].SetObject(puff);
 	if (numret > 1) ret[1].SetInt(acdmg), numret = 2;
 	return numret;

wadsrc/static/zscript/actor.txt

@@ -598,7 +598,7 @@ class Actor : Thinker native
 	native virtual int DamageMobj(Actor inflictor, Actor source, int damage, Name mod, int flags = 0, double angle = 0);
 	native void PoisonMobj (Actor inflictor, Actor source, int damage, int duration, int period, Name type);
 	native double AimLineAttack(double angle, double distance, out FTranslatedLineTarget pLineTarget = null, double vrange = 0., int flags = 0, Actor target = null, Actor friender = null);
-	native Actor, int LineAttack(double angle, double distance, double pitch, int damage, Name damageType, class<Actor> pufftype, int flags = 0, out FTranslatedLineTarget victim = null, double offsetz = 0.);
+	native Actor, int LineAttack(double angle, double distance, double pitch, int damage, Name damageType, class<Actor> pufftype, int flags = 0, out FTranslatedLineTarget victim = null, double offsetz = 0., double offsetforward = 0., double offsetside = 0.);
 	native bool CheckSight(Actor target, int flags = 0);
 	native bool IsVisible(Actor other, bool allaround, LookExParams params = null);
 	native bool HitFriend();

wadsrc/static/zscript/constants.txt

@@ -878,11 +878,14 @@ enum EAimFlags
 
 enum ELineAttackFlags
 {
-	LAF_ISMELEEATTACK = 1,
+	LAF_ISMELEEATTACK  = 1,
-	LAF_NORANDOMPUFFZ = 2,
+	LAF_NORANDOMPUFFZ  = 1 << 1,
-	LAF_NOIMPACTDECAL = 4,
+	LAF_NOIMPACTDECAL  = 1 << 2,
-	LAF_NOINTERACT =	8,
+	LAF_NOINTERACT     = 1 << 3,
-	LAF_OVERRIDEZ =		32,
+	LAF_TARGETISSOURCE = 1 << 4,
+	LAF_OVERRIDEZ      = 1 << 5,
+	LAF_ABSOFFSET      = 1 << 6,
+	LAF_ABSPOSITION    = 1 << 7,
 }
 
 const DEFMELEERANGE = 64;