diff --git a/src/doomdef.h b/src/doomdef.h
index c051a58b..0d98c31e 100644
--- a/src/doomdef.h
+++ b/src/doomdef.h
@@ -546,6 +546,6 @@ extern const char *compdate, *comptime, *comprevision, *compbranch;
 
 /// SRB2Kart: Camera always has noclip.
 /// \note   Kind of problematic. If we decide to keep this on, we'll need serious map changes.
-//#define NOCLIPCAM
+#define NOCLIPCAM
 
 #endif // __DOOMDEF__
diff --git a/src/hardware/hw_main.c b/src/hardware/hw_main.c
index 54362762..420efa17 100644
--- a/src/hardware/hw_main.c
+++ b/src/hardware/hw_main.c
@@ -2813,11 +2813,14 @@ static void HWR_AddLine(seg_t * line)
 		SLOPEPARAMS( gr_backsector->c_slope, backc1,  backc2,  gr_backsector->ceilingheight)
 #undef SLOPEPARAMS
 
-		// Closed door.
-		if ((backc1 <= frontf1 && backc2 <= frontf2)
-			|| (backf1 >= frontc1 && backf2 >= frontc2))
+		if (viewsector != gr_backsector && viewsector != gr_frontsector)
 		{
-			goto clipsolid;
+			// Closed door.
+			if ((backc1 <= frontf1 && backc2 <= frontf2)
+				|| (backf1 >= frontc1 && backf2 >= frontc2))
+			{
+				goto clipsolid;
+			}
 		}
 
 		// Window.
@@ -2830,10 +2833,13 @@ static void HWR_AddLine(seg_t * line)
 	else
 #endif
 	{
-		// Closed door.
-		if (gr_backsector->ceilingheight <= gr_frontsector->floorheight ||
-			gr_backsector->floorheight >= gr_frontsector->ceilingheight)
-			goto clipsolid;
+		if (viewsector != gr_backsector && viewsector != gr_frontsector)
+		{
+			// Closed door.
+			if (gr_backsector->ceilingheight <= gr_frontsector->floorheight ||
+				gr_backsector->floorheight >= gr_frontsector->ceilingheight)
+				goto clipsolid;
+		}
 
 		// Window.
 		if (gr_backsector->ceilingheight != gr_frontsector->ceilingheight ||
diff --git a/src/r_bsp.c b/src/r_bsp.c
index 82a7624b..c06c48dd 100644
--- a/src/r_bsp.c
+++ b/src/r_bsp.c
@@ -222,30 +222,6 @@ void R_PortalClearClipSegs(INT32 start, INT32 end)
 	newend = solidsegs + 2;
 }
 
-
-// R_DoorClosed
-//
-// This function is used to fix the automap bug which
-// showed lines behind closed doors simply because the door had a dropoff.
-//
-// It assumes that Doom has already ruled out a door being closed because
-// of front-back closure (e.g. front floor is taller than back ceiling).
-static INT32 R_DoorClosed(void)
-{
-	return
-
-	// if door is closed because back is shut:
-	backsector->ceilingheight <= backsector->floorheight
-
-	// preserve a kind of transparent door/lift special effect:
-	&& (backsector->ceilingheight >= frontsector->ceilingheight || curline->sidedef->toptexture)
-
-	&& (backsector->floorheight <= frontsector->floorheight || curline->sidedef->bottomtexture)
-
-	// properly render skies (consider door "open" if both ceilings are sky):
-	&& (backsector->ceilingpic != skyflatnum || frontsector->ceilingpic != skyflatnum);
-}
-
 //
 // If player's view height is underneath fake floor, lower the
 // drawn ceiling to be just under the floor height, and replace
@@ -502,21 +478,24 @@ static void R_AddLine(seg_t *line)
 		SLOPEPARAMS( backsector->f_slope, backf1,  backf2,  backsector->floorheight)
 		SLOPEPARAMS( backsector->c_slope, backc1,  backc2,  backsector->ceilingheight)
 #undef SLOPEPARAMS
-		if ((backc1 <= frontf1 && backc2 <= frontf2)
-			|| (backf1 >= frontc1 && backf2 >= frontc2))
+		if (viewsector != backsector && viewsector != frontsector)
 		{
-			goto clipsolid;
+			if ((backc1 <= frontf1 && backc2 <= frontf2)
+				|| (backf1 >= frontc1 && backf2 >= frontc2))
+			{
+				goto clipsolid;
+			}
+
+			// Check for automap fix. Store in doorclosed for r_segs.c
+			doorclosed = (backc1 <= backf1 && backc2 <= backf2
+			&& ((backc1 >= frontc1 && backc2 >= frontc2) || curline->sidedef->toptexture)
+			&& ((backf1 <= frontf1 && backf2 >= frontf2) || curline->sidedef->bottomtexture)
+			&& (backsector->ceilingpic != skyflatnum || frontsector->ceilingpic != skyflatnum));
+
+			if (doorclosed)
+				goto clipsolid;
 		}
 
-		// Check for automap fix. Store in doorclosed for r_segs.c
-		doorclosed = (backc1 <= backf1 && backc2 <= backf2
-		&& ((backc1 >= frontc1 && backc2 >= frontc2) || curline->sidedef->toptexture)
-		&& ((backf1 <= frontf1 && backf2 >= frontf2) || curline->sidedef->bottomtexture)
-		&& (backsector->ceilingpic != skyflatnum || frontsector->ceilingpic != skyflatnum));
-
-		if (doorclosed)
-			goto clipsolid;
-
 		// Window.
 		if (backc1 != frontc1 || backc2 != frontc2
 			|| backf1 != frontf1 || backf2 != frontf2)
@@ -527,16 +506,23 @@ static void R_AddLine(seg_t *line)
 	else
 #endif
 	{
-		if (backsector->ceilingheight <= frontsector->floorheight
-			|| backsector->floorheight >= frontsector->ceilingheight)
+		if (viewsector != backsector && viewsector != frontsector)
 		{
-			goto clipsolid;
-		}
+			if (backsector->ceilingheight <= frontsector->floorheight
+				|| backsector->floorheight >= frontsector->ceilingheight)
+			{
+				goto clipsolid;
+			}
 
-		// Check for automap fix. Store in doorclosed for r_segs.c
-		doorclosed = R_DoorClosed();
-		if (doorclosed)
-			goto clipsolid;
+			// Check for automap fix. Store in doorclosed for r_segs.c
+			doorclosed = (backsector->ceilingheight <= backsector->floorheight
+			&& (backsector->ceilingheight >= frontsector->ceilingheight || curline->sidedef->toptexture)
+			&& (backsector->floorheight <= frontsector->floorheight || curline->sidedef->bottomtexture)
+			&& (backsector->ceilingpic != skyflatnum || frontsector->ceilingpic != skyflatnum));
+
+			if (doorclosed)
+				goto clipsolid;
+		}
 
 		// Window.
 		if (backsector->ceilingheight != frontsector->ceilingheight
diff --git a/src/r_segs.c b/src/r_segs.c
index 11287f16..231a84f7 100644
--- a/src/r_segs.c
+++ b/src/r_segs.c
@@ -1365,7 +1365,7 @@ static void R_RenderSegLoop (void)
 			if (bottom >= floorclip[rw_x])
 				bottom = floorclip[rw_x]-1;
 
-			if (top <= bottom)
+			if (top <= bottom && ceilingplane)
 			{
 				ceilingplane->top[rw_x] = (INT16)top;
 				ceilingplane->bottom[rw_x] = (INT16)bottom;
@@ -2113,52 +2113,55 @@ void R_StoreWallRange(INT32 start, INT32 stop)
 			// ds_p->sprtopclip = screenheightarray;
 		}
 
-#ifdef ESLOPE
-		if (worldhigh <= worldbottom && worldhighslope <= worldbottomslope)
-#else
-		if (worldhigh <= worldbottom)
-#endif
-		{
-			ds_p->sprbottomclip = negonearray;
-			ds_p->bsilheight = INT32_MAX;
-			ds_p->silhouette |= SIL_BOTTOM;
-		}
-
-#ifdef ESLOPE
-		if (worldlow >= worldtop && worldlowslope >= worldtopslope)
-#else
-		if (worldlow >= worldtop)
-#endif
-		{
-			ds_p->sprtopclip = screenheightarray;
-			ds_p->tsilheight = INT32_MIN;
-			ds_p->silhouette |= SIL_TOP;
-		}
-
-		//SoM: 3/25/2000: This code fixes an automap bug that didn't check
-		// frontsector->ceiling and backsector->floor to see if a door was closed.
-		// Without the following code, sprites get displayed behind closed doors.
+		if (viewsector != frontsector && viewsector != backsector)
 		{
 #ifdef ESLOPE
-			if (doorclosed || (worldhigh <= worldbottom && worldhighslope <= worldbottomslope))
+			if (worldhigh <= worldbottom && worldhighslope <= worldbottomslope)
 #else
-			if (doorclosed || backsector->ceilingheight <= frontsector->floorheight)
+			if (worldhigh <= worldbottom)
 #endif
 			{
 				ds_p->sprbottomclip = negonearray;
 				ds_p->bsilheight = INT32_MAX;
 				ds_p->silhouette |= SIL_BOTTOM;
 			}
+
 #ifdef ESLOPE
-			if (doorclosed || (worldlow >= worldtop && worldlowslope >= worldtopslope))
+			if (worldlow >= worldtop && worldlowslope >= worldtopslope)
 #else
-			if (doorclosed || backsector->floorheight >= frontsector->ceilingheight)
+			if (worldlow >= worldtop)
 #endif
-			{                   // killough 1/17/98, 2/8/98
+			{
 				ds_p->sprtopclip = screenheightarray;
 				ds_p->tsilheight = INT32_MIN;
 				ds_p->silhouette |= SIL_TOP;
 			}
+
+			//SoM: 3/25/2000: This code fixes an automap bug that didn't check
+			// frontsector->ceiling and backsector->floor to see if a door was closed.
+			// Without the following code, sprites get displayed behind closed doors.
+			{
+#ifdef ESLOPE
+				if (doorclosed || (worldhigh <= worldbottom && worldhighslope <= worldbottomslope))
+#else
+				if (doorclosed || backsector->ceilingheight <= frontsector->floorheight)
+#endif
+				{
+					ds_p->sprbottomclip = negonearray;
+					ds_p->bsilheight = INT32_MAX;
+					ds_p->silhouette |= SIL_BOTTOM;
+				}
+#ifdef ESLOPE
+				if (doorclosed || (worldlow >= worldtop && worldlowslope >= worldtopslope))
+#else
+				if (doorclosed || backsector->floorheight >= frontsector->ceilingheight)
+#endif
+				{                   // killough 1/17/98, 2/8/98
+					ds_p->sprtopclip = screenheightarray;
+					ds_p->tsilheight = INT32_MIN;
+					ds_p->silhouette |= SIL_TOP;
+				}
+			}
 		}
 
 		if (worldlow != worldbottom