Add +ONLYVISIBLEINMIRRORS and +INVISIBLEINMIRRORS actor flags. The former makes the actor only visible in reflections, while the latter makes the actor not cast reflections in mirrors.

src/playsim/actor.h

@@ -477,6 +477,12 @@ enum ActorRenderFlag
 	RF_NOSPRITESHADOW = 0x80000000,		// actor will not cast a sprite shadow
 };
 
+enum ActorRenderFlag2
+{
+	RF2_INVISIBLEINMIRRORS		= 0x0001,	// [Nash] won't render in mirrors
+	RF2_ONLYVISIBLEINMIRRORS	= 0x0002,	// [Nash] only renders in mirrors
+};
+
 // This translucency value produces the closest match to Heretic's TINTTAB.
 // ~40% of the value of the overlaid image shows through.
 const double HR_SHADOW = (0x6800 / 65536.);
@@ -579,6 +585,7 @@ typedef TFlags<ActorFlag6> ActorFlags6;
 typedef TFlags<ActorFlag7> ActorFlags7;
 typedef TFlags<ActorFlag8> ActorFlags8;
 typedef TFlags<ActorRenderFlag> ActorRenderFlags;
+typedef TFlags<ActorRenderFlag2> ActorRenderFlags2;
 typedef TFlags<ActorBounceFlag> ActorBounceFlags;
 typedef TFlags<ActorRenderFeatureFlag> ActorRenderFeatureFlags;
 DEFINE_TFLAGS_OPERATORS (ActorFlags)
@@ -590,6 +597,7 @@ DEFINE_TFLAGS_OPERATORS (ActorFlags6)
 DEFINE_TFLAGS_OPERATORS (ActorFlags7)
 DEFINE_TFLAGS_OPERATORS (ActorFlags8)
 DEFINE_TFLAGS_OPERATORS (ActorRenderFlags)
+DEFINE_TFLAGS_OPERATORS (ActorRenderFlags2)
 DEFINE_TFLAGS_OPERATORS (ActorBounceFlags)
 DEFINE_TFLAGS_OPERATORS (ActorRenderFeatureFlags)
 
@@ -1037,6 +1045,7 @@ public:
 	uint32_t			RenderHidden;		// current renderer must *not* have any of these features
 
 	ActorRenderFlags	renderflags;		// Different rendering flags
+	ActorRenderFlags2	renderflags2;		// More rendering flags...
 	ActorFlags		flags;
 	ActorFlags2		flags2;			// Heretic flags
 	ActorFlags3		flags3;			// [RH] Hexen/Heretic actor-dependant behavior made flaggable

src/playsim/p_mobj.cpp

@@ -205,6 +205,7 @@ void AActor::Serialize(FSerializer &arc)
 		A("scale", Scale)
 		A("renderstyle", RenderStyle)
 		A("renderflags", renderflags)
+		A("renderflags2", renderflags2)
 		A("picnum", picnum)
 		A("floorpic", floorpic)
 		A("ceilingpic", ceilingpic)

src/rendering/hwrenderer/scene/hw_sprites.cpp

@@ -735,6 +735,17 @@ void HWSprite::Process(HWDrawInfo *di, AActor* thing, sector_t * sector, area_t
 		viewmaster = thing->master;
 	}
 
+	// [Nash] filter visibility in mirrors
+	bool isInMirror = di->mCurrentPortal && (di->mCurrentPortal->mState->MirrorFlag > 0 || di->mCurrentPortal->mState->PlaneMirrorFlag > 0);
+	if (thing->renderflags2 & RF2_INVISIBLEINMIRRORS && isInMirror)
+	{
+		return;
+	}
+	else if (thing->renderflags2 & RF2_ONLYVISIBLEINMIRRORS && !isInMirror)
+	{
+		return;
+	}
+
 	// Some added checks if the camera actor is not supposed to be seen. It can happen that some portal setup has this actor in view in which case it may not be skipped here
 	if (viewmaster == camera && !vp.showviewer)
 	{

src/rendering/swrenderer/scene/r_opaque_pass.cpp

@@ -1028,6 +1028,17 @@ namespace swrenderer
 		if (!renderportal->CurrentPortalInSkybox && renderportal->CurrentPortal && !!P_PointOnLineSidePrecise(thing->Pos(), renderportal->CurrentPortal->dst))
 			return false;
 
+		// [Nash] filter visibility in mirrors
+		bool isInMirror = renderportal != nullptr && renderportal->IsInMirrorRecursively;
+		if (thing->renderflags2 & RF2_INVISIBLEINMIRRORS && isInMirror)
+		{
+			return false;
+		}
+		else if (thing->renderflags2 & RF2_ONLYVISIBLEINMIRRORS && !isInMirror)
+		{
+			return false;
+		}
+
 		double distanceSquared = (thing->Pos() - Thread->Viewport->viewpoint.Pos).LengthSquared();
 		if (distanceSquared > sprite_distance_cull)
 			return false;

src/rendering/swrenderer/scene/r_portal.cpp

@@ -339,6 +339,8 @@ namespace swrenderer
 
 		if (pds->mirror)
 		{
+			IsInMirrorRecursively = true;
+
 			//vertex_t *v1 = ds->curline->v1;
 			vertex_t *v1 = pds->src->v1;
 
@@ -465,6 +467,7 @@ namespace swrenderer
 
 		CurrentPortal = prevpds;
 		MirrorFlags = prevmf;
+		IsInMirrorRecursively = false;
 		viewpoint.Angles.Yaw = startang;
 		viewpoint.Pos = startpos;
 		viewpoint.Path[0] = savedpath[0];

src/rendering/swrenderer/scene/r_portal.h

@@ -48,6 +48,10 @@ namespace swrenderer
 		int WindowRight = 0;
 		uint16_t MirrorFlags = 0;
 
+		// [Nash] this is set when first entering a mirror portal, and is unset when leaving the final mirror portal recursion
+		// Used for the RF2_INVISIBLEINMIRRORS and RF2_ONLYVISIBLEINMIRRORS features
+		bool IsInMirrorRecursively = false;
+
 		PortalDrawseg* CurrentPortal = nullptr;
 		int CurrentPortalUniq = 0;
 		bool CurrentPortalInSkybox = false;

src/scripting/thingdef_data.cpp

@@ -368,6 +368,8 @@ static FFlagDef ActorFlagDefs[]=
 	DEFINE_FLAG(RF, ZDOOMTRANS, AActor, renderflags),
 	DEFINE_FLAG(RF, CASTSPRITESHADOW, AActor, renderflags),
 	DEFINE_FLAG(RF, NOSPRITESHADOW, AActor, renderflags),
+	DEFINE_FLAG(RF2, INVISIBLEINMIRRORS, AActor, renderflags2),
+	DEFINE_FLAG(RF2, ONLYVISIBLEINMIRRORS, AActor, renderflags2),
 
 	// Bounce flags
 	DEFINE_FLAG2(BOUNCE_Walls, BOUNCEONWALLS, AActor, BounceFlags),