- fixed attached dynamic light setup.

This was only run on a state change and missed every external light change.
Any place which wants to flag a light change now only will set a flag and at the end of the thinker loop all flagged actors will be processed.
For performance reasons this was merged with the P_RunEffects iterator loop.

src/p_tick.cpp

@@ -134,7 +134,6 @@ void P_Ticker (void)
 	for (auto Level : AllLevels())
 	{
 		// todo: set up a sandbox for secondary levels here.
-
 		auto it = Level->GetThinkerIterator<AActor>();
 		AActor *ac;
 
@@ -142,6 +141,7 @@ void P_Ticker (void)
 		{
 			ac->ClearInterpolation();
 		}
+
 		P_ThinkParticles(Level);	// [RH] make the particles think
 
 		for (i = 0; i < MAXPLAYERS; i++)
@@ -157,7 +157,22 @@ void P_Ticker (void)
 		if (!Level->isFrozen())
 		{
 			P_UpdateSpecials(Level);
-			P_RunEffects(Level);	// [RH] Run particle effects
+		}
+		it = Level->GetThinkerIterator<AActor>();
+
+		// Set dynamic lights at the end of the tick, so that this catches all changes being made through the last frame.
+		while ((ac = it.Next()))
+		{
+			if (ac->flags8 & MF8_RECREATELIGHTS)
+			{
+				ac->flags8 &= ~MF8_RECREATELIGHTS;
+				ac->SetDynamicLights();
+			}
+			// This was merged from P_RunEffects to eliminate the costly duplicate ThinkerIterator loop.
+			if ((ac->effects || ac->fountaincolor) && !Level->isFrozen())
+			{
+				P_RunEffect(ac, ac->effects);
+			}
 		}
 
 		// for par times

src/playsim/a_dynlight.cpp

@@ -764,17 +764,11 @@ void AActor::SetDynamicLights()
 		AttachLight(count++, def);
 	}
 
-	if (LightAssociations.Size() > 0)
+	for (const auto asso : LightAssociations)
 	{
-		unsigned int i;
+		if (asso->Sprite() == sprite && (asso->Frame() == frame || asso->Frame() == -1))
-
-		for (i = 0; i < LightAssociations.Size(); i++)
 		{
-			if (LightAssociations[i]->Sprite() == sprite &&
+			AttachLight(count++, asso->Light());
-				(LightAssociations[i]->Frame()==frame || LightAssociations[i]->Frame()==-1))
-			{
-				AttachLight(count++, LightAssociations[i]->Light());
-			}
 		}
 	}
 	if (count == 0 && state->Light > 0)
@@ -850,6 +844,7 @@ int AttachLightDef(AActor *self, int _lightid, int _lightname)
 	{
 		auto userlight = self->UserLights[FindUserLight(self, lightid, true)];
 		userlight->CopyFrom(*LightDefaults[lightdef]);
+		self->flags8 |= MF8_RECREATELIGHTS;
 		return 1;
 	}
 	return 0;
@@ -893,7 +888,7 @@ int AttachLightDirect(AActor *self, int _lightid, int type, int color, int radiu
 	{
 		userlight->UnsetSpotPitch();
 	}
-
+	self->flags8 |= MF8_RECREATELIGHTS;
 	return 1;
 }
 
@@ -930,8 +925,10 @@ int RemoveLight(AActor *self, int _lightid)
 	{
 		delete self->UserLights[userlight];
 		self->UserLights.Delete(userlight);
+		self->flags8 |= MF8_RECREATELIGHTS;
+		return 1;
 	}
-	return 1;
+	return 0;
 }
 
 DEFINE_ACTION_FUNCTION_NATIVE(AActor, A_RemoveLight, RemoveLight)

src/playsim/actor.h

@@ -409,7 +409,8 @@ enum ActorFlag8
 	MF8_HITOWNER		= 0x00000010,	// projectile can hit the actor that fired it
 	MF8_NOFRICTION		= 0x00000020,	// friction doesn't apply to the actor at all
 	MF8_NOFRICTIONBOUNCE	= 0x00000040,	// don't bounce off walls when on icy floors
-	MF8_RETARGETAFTERSLAM	= 0x00000080	// Forces jumping to the idle state after slamming into something
+	MF8_RETARGETAFTERSLAM	= 0x00000080,	// Forces jumping to the idle state after slamming into something
+	MF8_RECREATELIGHTS	= 0x00000100,	// Internal flag that signifies that the light attachments need to be recreated at the
 };
 
 // --- mobj.renderflags ---

src/playsim/p_effect.cpp

@@ -299,25 +299,6 @@ void P_SpawnParticle(FLevelLocals *Level, const DVector3 &pos, const DVector3 &v
 	}
 }
 
-//
-// P_RunEffects
-//
-// Run effects on all actors in the world
-//
-void P_RunEffects (FLevelLocals *Level)
-{
-	AActor *actor;
-	auto iterator = Level->GetThinkerIterator<AActor>();
-
-	while ( (actor = iterator.Next ()) )
-	{
-		if (actor->effects || actor->fountaincolor)
-		{
-			P_RunEffect (actor, actor->effects);
-		}
-	}
-}
-
 //
 // JitterParticle
 //

src/playsim/p_effect.h

@@ -78,7 +78,6 @@ particle_t *JitterParticle (FLevelLocals *Level, int ttl, double drift);
 void P_ThinkParticles (FLevelLocals *Level);
 void P_SpawnParticle(FLevelLocals *Level, const DVector3 &pos, const DVector3 &vel, const DVector3 &accel, PalEntry color, double startalpha, int lifetime, double size, double fadestep, double sizestep, int flags = 0);
 void P_InitEffects (void);
-void P_RunEffects (FLevelLocals *Level);
 
 void P_RunEffect (AActor *actor, int effects);
 

src/playsim/p_mobj.cpp

@@ -577,7 +577,7 @@ bool AActor::SetState (FState *newstate, bool nofunction)
 		newstate = newstate->GetNextState();
 	} while (tics == 0);
 
-	SetDynamicLights();
+	flags8 |= MF8_RECREATELIGHTS;
 	return true;
 }
 
@@ -4702,9 +4702,9 @@ void AActor::CallBeginPlay()
 
 void AActor::PostBeginPlay ()
 {
-	SetDynamicLights();
 	PrevAngles = Angles;
 	flags7 |= MF7_HANDLENODELAY;
+	flags8 |= MF8_RECREATELIGHTS;
 }
 
 void AActor::CallPostBeginPlay()