- some preparations for portal stuff:

* set up linked sector portals so that everything that will eventually have to be considered is present, even though the software renderer currently can't handle those adequately.
* tag all skybox things with a type so that they can easily be distinguished at run time.
* fill in the linked portal types in xlat/eternity.txt.

src/g_shared/a_sharedglobal.h

@@ -106,11 +106,7 @@ class ASkyCamCompat : public ASkyViewpoint
 	DECLARE_CLASS (ASkyCamCompat, ASkyViewpoint)
 
 public:
-	void BeginPlay ()
-	{
-		// Do not call the SkyViewpoint's super method because it would trash our setup
-		AActor::BeginPlay();
-	}
+	void BeginPlay();
 };
 
 

src/g_shared/a_skies.cpp

@@ -54,6 +54,7 @@ void ASkyViewpoint::BeginPlay ()
 	{
 		level.DefaultSkybox = this;
 	}
+	special1 = SKYBOX_SKYVIEWPOINT;
 }
 
 void ASkyViewpoint::Serialize (FArchive &arc)
@@ -85,6 +86,13 @@ void ASkyViewpoint::Destroy ()
 
 IMPLEMENT_CLASS (ASkyCamCompat)
 
+void ASkyCamCompat::BeginPlay()
+{
+	// Do not call the SkyViewpoint's super method because it would trash our setup
+	AActor::BeginPlay();
+	special1 = SKYBOX_SKYVIEWPOINT;
+}
+
 
 //---------------------------------------------------------------------------
 
@@ -154,6 +162,7 @@ void AStackPoint::BeginPlay ()
 	AActor::BeginPlay ();
 
 	bAlways = true;
+	special1 = SKYBOX_STACKEDSECTORTHING;
 }
 
 //---------------------------------------------------------------------------

src/p_spec.cpp

@@ -1019,15 +1019,16 @@ static void CopyPortal(int sectortag, int plane, ASkyViewpoint *origin, fixed_t
 	}
 }
 
-void P_SpawnPortal(line_t *line, int sectortag, int plane, int alpha)
+void P_SpawnPortal(line_t *line, int sectortag, int plane, int alpha, int linked)
 {
+	if (plane < 0 || plane > 2 || (linked && plane == 2)) return;
 	for (int i=0;i<numlines;i++)
 	{
 		// We must look for the reference line with a linear search unless we want to waste the line ID for it
 		// which is not a good idea.
 		if (lines[i].special == Sector_SetPortal &&
 			lines[i].args[0] == sectortag &&
-			lines[i].args[1] == 0 &&
+			lines[i].args[1] == linked &&
 			lines[i].args[2] == plane &&
 			lines[i].args[3] == 1)
 		{
@@ -1036,10 +1037,18 @@ void P_SpawnPortal(line_t *line, int sectortag, int plane, int alpha)
 			fixed_t y1 = fixed_t((SQWORD(line->v1->y) + SQWORD(line->v2->y)) >> 1);
 			fixed_t x2 = fixed_t((SQWORD(lines[i].v1->x) + SQWORD(lines[i].v2->x)) >> 1);
 			fixed_t y2 = fixed_t((SQWORD(lines[i].v1->y) + SQWORD(lines[i].v2->y)) >> 1);
+			fixed_t z = linked ? line->frontsector->planes[plane].TexZ : 0;	// the map's sector height defines the portal plane for linked portals
+
 			fixed_t alpha = Scale (lines[i].args[4], OPAQUE, 255);
 
 			AStackPoint *anchor = Spawn<AStackPoint>(x1, y1, 0, NO_REPLACE);
 			AStackPoint *reference = Spawn<AStackPoint>(x2, y2, 0, NO_REPLACE);
+			reference->special1 = linked ? SKYBOX_LINKEDPORTAL : SKYBOX_PORTAL;
+			anchor->special1 = SKYBOX_ANCHOR;
+			// store the portal displacement in the unused scaleX/Y members of the portal reference actor.
+			anchor->scaleX = -(reference->scaleX = x2 - x1);
+			anchor->scaleY = -(reference->scaleY = y2 - y1);
+			anchor->threshold = reference->threshold = z;
 
 			reference->Mate = anchor;
 			anchor->Mate = reference;
@@ -1427,13 +1436,17 @@ void P_SpawnSpecials (void)
 			//	- 0: normal (handled here)
 			//	- 1: copy (handled by the portal they copy)
 			//	- 2: EE-style skybox (handled by the camera object)
+			//  - 3: EE-style flat portal (GZDoom HW renderer only for now)
+			//  - 4: EE-style horizon portal (GZDoom HW renderer only for now)
+			//  - 5: copy portal to line (GZDoom HW renderer only for now)
+			//  - 6: linked portal
 			//	other values reserved for later use
 			// arg 2 = 0:floor, 1:ceiling, 2:both
 			// arg 3 = 0: anchor, 1: reference line
 			// arg 4 = for the anchor only: alpha
-			if (lines[i].args[1] == 0 && lines[i].args[3] == 0)
+			if ((lines[i].args[1] == 0 || lines[i].args[1] == 6) && lines[i].args[3] == 0)
 			{
-				P_SpawnPortal(&lines[i], lines[i].args[0], lines[i].args[2], lines[i].args[4]);
+				P_SpawnPortal(&lines[i], lines[i].args[0], lines[i].args[2], lines[i].args[4], lines[i].args[1]);
 			}
 			break;
 
@@ -1510,6 +1523,7 @@ void P_SpawnSpecials (void)
 			break;
 		}
 	}
+	P_CreateLinkedPortals();
 	// [RH] Start running any open scripts on this map
 	FBehavior::StaticStartTypedScripts (SCRIPT_Open, NULL, false);
 	P_FinalizePortals();

src/portal.cpp

@@ -504,3 +504,8 @@ bool PortalTracer::TraceStep()
 	return (oDepth != depth); // if a portal has been found, return false
 }
 
+void P_CreateLinkedPortals()
+{
+}
+
+

src/portal.h

@@ -53,6 +53,7 @@ extern TArray<FLinePortal> linePortals;
 void P_SpawnLinePortal(line_t* line);
 void P_FinalizePortals();
 bool P_ChangePortal(line_t *ln, int thisid, int destid);
+void P_CreateLinkedPortals();
 
 
 /* code ported from prototype */

src/r_bsp.cpp

@@ -1094,6 +1094,7 @@ void R_Subsector (subsector_t *sub)
 	}
 
 	skybox = frontsector->GetSkyBox(sector_t::ceiling);
+	if (skybox != NULL && skybox->special1 >= SKYBOX_PLANE) skybox = NULL;	// skip unsupported portal types
 
 	ceilingplane = frontsector->ceilingplane.PointOnSide(viewx, viewy, viewz) > 0 ||
 		frontsector->GetTexture(sector_t::ceiling) == skyflatnum ||
@@ -1135,6 +1136,8 @@ void R_Subsector (subsector_t *sub)
 	// killough 3/16/98: add floorlightlevel
 	// killough 10/98: add support for skies transferred from sidedefs
 	skybox = frontsector->GetSkyBox(sector_t::floor);
+	if (skybox != NULL && skybox->special1 >= SKYBOX_PLANE) skybox = NULL;	// skip unsupported portal types
+
 	floorplane = frontsector->floorplane.PointOnSide(viewx, viewy, viewz) > 0 || // killough 3/7/98
 		frontsector->GetTexture(sector_t::floor) == skyflatnum ||
 		(skybox != NULL && skybox->bAlways) ||

src/r_defs.h

@@ -57,6 +57,18 @@ enum
 extern size_t MaxDrawSegs;
 
 
+enum
+{
+	SKYBOX_ANCHOR = -1,
+	SKYBOX_SKYVIEWPOINT = 0,				// a regular skybox
+	SKYBOX_STACKEDSECTORTHING,	// stacked sectors with the thing method
+	SKYBOX_PORTAL,				// stacked sectors with Sector_SetPortal
+	SKYBOX_LINKEDPORTAL,		// linked portal (interactive)
+	SKYBOX_PLANE,				// EE-style plane portal (not implemented in SW renderer)
+	SKYBOX_HORIZON,				// EE-style horizon portal (not implemented in SW renderer)
+};
+
+
 //
 // INTERNAL MAP TYPES
 //	used by play and refresh

wadsrc/static/xlat/eternity.txt

@@ -132,10 +132,10 @@ enum
 357 = 0, Polyobj_OR_RotateLeft(0)
 
 // Eternity's linked portals, vertical link version (floor-to-ceiling)
-358 = 0,	Unsupported() // "Portal_LinkedCeiling"
-359 = 0,	Unsupported() // "Portal_LinkedFloor"
-360 = 0,	Unsupported() // "Portal_LinkedAnchorLine"
-361 = 0,	Unsupported() // "Portal_LinkedAnchorLineFloor"
+358 = 0,	Sector_SetPortal(tag, 6, 1, 1, 0) // "Portal_AnchoredCeiling"
+359 = 0,	Sector_SetPortal(tag, 6, 0, 1, 0) // "Portal_AnchoredFloor"
+360 = 0,	Sector_SetPortal(tag, 6, 1, 0, 0) // "Portal_AnchorLine"
+361 = 0,	Sector_SetPortal(tag, 6, 0, 0, 0) // "Portal_AnchorLineFloor"
 
 // Even more parameterized linedefs
 362 = 0, Pillar_Build(0)