diff --git a/src/deh_tables.c b/src/deh_tables.c
index 106e5178569fb90a3a82dddf957f3479da5ec089..e45d552c9e601461e5c29025d9e7cb662ce966c0 100644
--- a/src/deh_tables.c
+++ b/src/deh_tables.c
@@ -5326,42 +5326,81 @@ struct int_const_s const INT_CONST[] = {
 	{"SKSJUMP",SKSJUMP},
 
 	// 3D Floor/Fake Floor/FOF/whatever flags
-	{"FF_EXISTS",FF_EXISTS},                   ///< Always set, to check for validity.
-	{"FF_BLOCKPLAYER",FF_BLOCKPLAYER},         ///< Solid to player, but nothing else
-	{"FF_BLOCKOTHERS",FF_BLOCKOTHERS},         ///< Solid to everything but player
-	{"FF_SOLID",FF_SOLID},                     ///< Clips things.
-	{"FF_RENDERSIDES",FF_RENDERSIDES},         ///< Renders the sides.
-	{"FF_RENDERPLANES",FF_RENDERPLANES},       ///< Renders the floor/ceiling.
-	{"FF_RENDERALL",FF_RENDERALL},             ///< Renders everything.
-	{"FF_SWIMMABLE",FF_SWIMMABLE},             ///< Is a water block.
-	{"FF_NOSHADE",FF_NOSHADE},                 ///< Messes with the lighting?
-	{"FF_CUTSOLIDS",FF_CUTSOLIDS},             ///< Cuts out hidden solid pixels.
-	{"FF_CUTEXTRA",FF_CUTEXTRA},               ///< Cuts out hidden translucent pixels.
-	{"FF_CUTLEVEL",FF_CUTLEVEL},               ///< Cuts out all hidden pixels.
-	{"FF_CUTSPRITES",FF_CUTSPRITES},           ///< Final step in making 3D water.
-	{"FF_BOTHPLANES",FF_BOTHPLANES},           ///< Render inside and outside planes.
-	{"FF_EXTRA",FF_EXTRA},                     ///< Gets cut by ::FF_CUTEXTRA.
-	{"FF_TRANSLUCENT",FF_TRANSLUCENT},         ///< See through!
-	{"FF_FOG",FF_FOG},                         ///< Fog "brush."
-	{"FF_INVERTPLANES",FF_INVERTPLANES},       ///< Only render inside planes.
-	{"FF_ALLSIDES",FF_ALLSIDES},               ///< Render inside and outside sides.
-	{"FF_INVERTSIDES",FF_INVERTSIDES},         ///< Only render inside sides.
-	{"FF_DOUBLESHADOW",FF_DOUBLESHADOW},       ///< Make two lightlist entries to reset light?
-	{"FF_FLOATBOB",FF_FLOATBOB},               ///< Floats on water and bobs if you step on it.
-	{"FF_NORETURN",FF_NORETURN},               ///< Used with ::FF_CRUMBLE. Will not return to its original position after falling.
-	{"FF_CRUMBLE",FF_CRUMBLE},                 ///< Falls 2 seconds after being stepped on, and randomly brings all touching crumbling 3dfloors down with it, providing their master sectors share the same tag (allows crumble platforms above or below, to also exist).
-	{"FF_GOOWATER",FF_GOOWATER},               ///< Used with ::FF_SWIMMABLE. Makes thick bouncey goop.
-	{"FF_MARIO",FF_MARIO},                     ///< Acts like a question block when hit from underneath. Goodie spawned at top is determined by master sector.
-	{"FF_BUSTUP",FF_BUSTUP},                   ///< You can spin through/punch this block and it will crumble!
-	{"FF_QUICKSAND",FF_QUICKSAND},             ///< Quicksand!
-	{"FF_PLATFORM",FF_PLATFORM},               ///< You can jump up through this to the top.
-	{"FF_REVERSEPLATFORM",FF_REVERSEPLATFORM}, ///< A fall-through floor in normal gravity, a platform in reverse gravity.
-	{"FF_INTANGIBLEFLATS",FF_INTANGIBLEFLATS}, ///< Both flats are intangible, but the sides are still solid.
-	{"FF_INTANGABLEFLATS",FF_INTANGIBLEFLATS}, ///< Both flats are intangable, but the sides are still solid.
-	{"FF_RIPPLE",FF_RIPPLE},                   ///< Ripple the flats
-	{"FF_COLORMAPONLY",FF_COLORMAPONLY},       ///< Only copy the colormap, not the lightlevel
-	{"FF_BOUNCY",FF_BOUNCY},                   ///< Bounces players
-	{"FF_SPLAT",FF_SPLAT},                     ///< Use splat flat renderer (treat cyan pixels as invisible)
+	{"FOF_EXISTS",FOF_EXISTS},                   ///< Always set, to check for validity.
+	{"FOF_BLOCKPLAYER",FOF_BLOCKPLAYER},         ///< Solid to player, but nothing else
+	{"FOF_BLOCKOTHERS",FOF_BLOCKOTHERS},         ///< Solid to everything but player
+	{"FOF_SOLID",FOF_SOLID},                     ///< Clips things.
+	{"FOF_RENDERSIDES",FOF_RENDERSIDES},         ///< Renders the sides.
+	{"FOF_RENDERPLANES",FOF_RENDERPLANES},       ///< Renders the floor/ceiling.
+	{"FOF_RENDERALL",FOF_RENDERALL},             ///< Renders everything.
+	{"FOF_SWIMMABLE",FOF_SWIMMABLE},             ///< Is a water block.
+	{"FOF_NOSHADE",FOF_NOSHADE},                 ///< Messes with the lighting?
+	{"FOF_CUTSOLIDS",FOF_CUTSOLIDS},             ///< Cuts out hidden solid pixels.
+	{"FOF_CUTEXTRA",FOF_CUTEXTRA},               ///< Cuts out hidden translucent pixels.
+	{"FOF_CUTLEVEL",FOF_CUTLEVEL},               ///< Cuts out all hidden pixels.
+	{"FOF_CUTSPRITES",FOF_CUTSPRITES},           ///< Final step in making 3D water.
+	{"FOF_BOTHPLANES",FOF_BOTHPLANES},           ///< Render inside and outside planes.
+	{"FOF_EXTRA",FOF_EXTRA},                     ///< Gets cut by ::FOF_CUTEXTRA.
+	{"FOF_TRANSLUCENT",FOF_TRANSLUCENT},         ///< See through!
+	{"FOF_FOG",FOF_FOG},                         ///< Fog "brush."
+	{"FOF_INVERTPLANES",FOF_INVERTPLANES},       ///< Only render inside planes.
+	{"FOF_ALLSIDES",FOF_ALLSIDES},               ///< Render inside and outside sides.
+	{"FOF_INVERTSIDES",FOF_INVERTSIDES},         ///< Only render inside sides.
+	{"FOF_DOUBLESHADOW",FOF_DOUBLESHADOW},       ///< Make two lightlist entries to reset light?
+	{"FOF_FLOATBOB",FOF_FLOATBOB},               ///< Floats on water and bobs if you step on it.
+	{"FOF_NORETURN",FOF_NORETURN},               ///< Used with ::FOF_CRUMBLE. Will not return to its original position after falling.
+	{"FOF_CRUMBLE",FOF_CRUMBLE},                 ///< Falls 2 seconds after being stepped on, and randomly brings all touching crumbling 3dfloors down with it, providing their master sectors share the same tag (allows crumble platforms above or below, to also exist).
+	{"FOF_GOOWATER",FOF_GOOWATER},               ///< Used with ::FOF_SWIMMABLE. Makes thick bouncey goop.
+	{"FOF_MARIO",FOF_MARIO},                     ///< Acts like a question block when hit from underneath. Goodie spawned at top is determined by master sector.
+	{"FOF_BUSTUP",FOF_BUSTUP},                   ///< You can spin through/punch this block and it will crumble!
+	{"FOF_QUICKSAND",FOF_QUICKSAND},             ///< Quicksand!
+	{"FOF_PLATFORM",FOF_PLATFORM},               ///< You can jump up through this to the top.
+	{"FOF_REVERSEPLATFORM",FOF_REVERSEPLATFORM}, ///< A fall-through floor in normal gravity, a platform in reverse gravity.
+	{"FOF_INTANGIBLEFLATS",FOF_INTANGIBLEFLATS}, ///< Both flats are intangible, but the sides are still solid.
+	{"FOF_RIPPLE",FOF_RIPPLE},                   ///< Ripple the flats
+	{"FOF_COLORMAPONLY",FOF_COLORMAPONLY},       ///< Only copy the colormap, not the lightlevel
+	{"FOF_BOUNCY",FOF_BOUNCY},                   ///< Bounces players
+	{"FOF_SPLAT",FOF_SPLAT},                     ///< Use splat flat renderer (treat cyan pixels as invisible)
+
+	// Old FOF flags for backwards compatibility
+	{"FF_EXISTS",FF_OLD_EXISTS},
+	{"FF_BLOCKPLAYER",FF_OLD_BLOCKPLAYER},
+	{"FF_BLOCKOTHERS",FF_OLD_BLOCKOTHERS},
+	{"FF_SOLID",FF_OLD_SOLID},
+	{"FF_RENDERSIDES",FF_OLD_RENDERSIDES},
+	{"FF_RENDERPLANES",FF_OLD_RENDERPLANES},
+	{"FF_RENDERALL",FF_OLD_RENDERALL},
+	{"FF_SWIMMABLE",FF_OLD_SWIMMABLE},
+	{"FF_NOSHADE",FF_OLD_NOSHADE},
+	{"FF_CUTSOLIDS",FF_OLD_CUTSOLIDS},
+	{"FF_CUTEXTRA",FF_OLD_CUTEXTRA},
+	{"FF_CUTLEVEL",FF_OLD_CUTLEVEL},
+	{"FF_CUTSPRITES",FF_OLD_CUTSPRITES},
+	{"FF_BOTHPLANES",FF_OLD_BOTHPLANES},
+	{"FF_EXTRA",FF_OLD_EXTRA},
+	{"FF_TRANSLUCENT",FF_OLD_TRANSLUCENT},
+	{"FF_FOG",FF_OLD_FOG},
+	{"FF_INVERTPLANES",FF_OLD_INVERTPLANES},
+	{"FF_ALLSIDES",FF_OLD_ALLSIDES},
+	{"FF_INVERTSIDES",FF_OLD_INVERTSIDES},
+	{"FF_DOUBLESHADOW",FF_OLD_DOUBLESHADOW},
+	{"FF_FLOATBOB",FF_OLD_FLOATBOB},
+	{"FF_NORETURN",FF_OLD_NORETURN},
+	{"FF_CRUMBLE",FF_OLD_CRUMBLE},
+	{"FF_SHATTERBOTTOM",FF_OLD_SHATTERBOTTOM},
+	{"FF_GOOWATER",FF_OLD_GOOWATER},
+	{"FF_MARIO",FF_OLD_MARIO},
+	{"FF_BUSTUP",FF_OLD_BUSTUP},
+	{"FF_QUICKSAND",FF_OLD_QUICKSAND},
+	{"FF_PLATFORM",FF_OLD_PLATFORM},
+	{"FF_REVERSEPLATFORM",FF_OLD_REVERSEPLATFORM},
+	{"FF_INTANGIBLEFLATS",FF_OLD_INTANGIBLEFLATS},
+	{"FF_INTANGABLEFLATS",FF_OLD_INTANGIBLEFLATS},
+	{"FF_SHATTER",FF_OLD_SHATTER},
+	{"FF_SPINBUST",FF_OLD_SPINBUST},
+	{"FF_STRONGBUST",FF_OLD_STRONGBUST},
+	{"FF_RIPPLE",FF_OLD_RIPPLE},
+	{"FF_COLORMAPONLY",FF_OLD_COLORMAPONLY},
 
 	// FOF bustable flags
 	{"FB_PUSHABLES",FB_PUSHABLES},
diff --git a/src/hardware/hw_main.c b/src/hardware/hw_main.c
index 4400c547675308e75cb14ac064f512f036613e73..9793a5f690aef4c9f84a2417aadb3581062e9f19 100644
--- a/src/hardware/hw_main.c
+++ b/src/hardware/hw_main.c
@@ -887,9 +887,9 @@ static void HWR_SplitWall(sector_t *sector, FOutVector *wallVerts, INT32 texnum,
 		if (endtop < endrealbot && top < realbot)
 			return;
 
-		if (!(list[i].flags & FF_NOSHADE))
+		if (!(list[i].flags & FOF_NOSHADE))
 		{
-			if (pfloor && (pfloor->flags & FF_FOG))
+			if (pfloor && (pfloor->fofflags & FOF_FOG))
 			{
 				lightnum = HWR_CalcWallLight(pfloor->master->frontsector->lightlevel, v1x, v1y, v2x, v2y);
 				colormap = pfloor->master->frontsector->extra_colormap;
@@ -903,13 +903,13 @@ static void HWR_SplitWall(sector_t *sector, FOutVector *wallVerts, INT32 texnum,
 
 		solid = false;
 
-		if ((sector->lightlist[i].flags & FF_CUTSOLIDS) && !(cutflag & FF_EXTRA))
+		if ((sector->lightlist[i].flags & FOF_CUTSOLIDS) && !(cutflag & FOF_EXTRA))
 			solid = true;
-		else if ((sector->lightlist[i].flags & FF_CUTEXTRA) && (cutflag & FF_EXTRA))
+		else if ((sector->lightlist[i].flags & FOF_CUTEXTRA) && (cutflag & FOF_EXTRA))
 		{
-			if (sector->lightlist[i].flags & FF_EXTRA)
+			if (sector->lightlist[i].flags & FOF_EXTRA)
 			{
-				if ((sector->lightlist[i].flags & (FF_FOG|FF_SWIMMABLE)) == (cutflag & (FF_FOG|FF_SWIMMABLE))) // Only merge with your own types
+				if ((sector->lightlist[i].flags & (FOF_FOG|FOF_SWIMMABLE)) == (cutflag & (FOF_FOG|FOF_SWIMMABLE))) // Only merge with your own types
 					solid = true;
 			}
 			else
@@ -978,7 +978,7 @@ static void HWR_SplitWall(sector_t *sector, FOutVector *wallVerts, INT32 texnum,
 		wallVerts[0].y = bot;
 		wallVerts[1].y = endbot;
 
-		if (cutflag & FF_FOG)
+		if (cutflag & FOF_FOG)
 			HWR_AddTransparentWall(wallVerts, Surf, texnum, PF_Fog|PF_NoTexture|polyflags, true, lightnum, colormap);
 		else if (polyflags & (PF_Translucent|PF_Additive|PF_Subtractive|PF_ReverseSubtract|PF_Multiplicative|PF_Environment))
 			HWR_AddTransparentWall(wallVerts, Surf, texnum, polyflags, false, lightnum, colormap);
@@ -1007,7 +1007,7 @@ static void HWR_SplitWall(sector_t *sector, FOutVector *wallVerts, INT32 texnum,
 	wallVerts[0].y = bot;
 	wallVerts[1].y = endbot;
 
-	if (cutflag & FF_FOG)
+	if (cutflag & FOF_FOG)
 		HWR_AddTransparentWall(wallVerts, Surf, texnum, PF_Fog|PF_NoTexture|polyflags, true, lightnum, colormap);
 	else if (polyflags & (PF_Translucent|PF_Additive|PF_Subtractive|PF_ReverseSubtract|PF_Multiplicative|PF_Environment))
 		HWR_AddTransparentWall(wallVerts, Surf, texnum, polyflags, false, lightnum, colormap);
@@ -1192,7 +1192,7 @@ static void HWR_ProcessSeg(void) // Sort of like GLWall::Process in GZDoom
 			wallVerts[1].y = FIXED_TO_FLOAT(worldhighslope);
 
 			if (gl_frontsector->numlights)
-				HWR_SplitWall(gl_frontsector, wallVerts, gl_toptexture, &Surf, FF_CUTLEVEL, NULL, 0);
+				HWR_SplitWall(gl_frontsector, wallVerts, gl_toptexture, &Surf, FOF_CUTLEVEL, NULL, 0);
 			else if (grTex->mipmap.flags & TF_TRANSPARENT)
 				HWR_AddTransparentWall(wallVerts, &Surf, gl_toptexture, PF_Environment, false, lightnum, colormap);
 			else
@@ -1258,7 +1258,7 @@ static void HWR_ProcessSeg(void) // Sort of like GLWall::Process in GZDoom
 			wallVerts[1].y = FIXED_TO_FLOAT(worldbottomslope);
 
 			if (gl_frontsector->numlights)
-				HWR_SplitWall(gl_frontsector, wallVerts, gl_bottomtexture, &Surf, FF_CUTLEVEL, NULL, 0);
+				HWR_SplitWall(gl_frontsector, wallVerts, gl_bottomtexture, &Surf, FOF_CUTLEVEL, NULL, 0);
 			else if (grTex->mipmap.flags & TF_TRANSPARENT)
 				HWR_AddTransparentWall(wallVerts, &Surf, gl_bottomtexture, PF_Environment, false, lightnum, colormap);
 			else
@@ -1465,9 +1465,9 @@ static void HWR_ProcessSeg(void) // Sort of like GLWall::Process in GZDoom
 			if (gl_frontsector->numlights)
 			{
 				if (!(blendmode & PF_Masked))
-					HWR_SplitWall(gl_frontsector, wallVerts, gl_midtexture, &Surf, FF_TRANSLUCENT, NULL, blendmode);
+					HWR_SplitWall(gl_frontsector, wallVerts, gl_midtexture, &Surf, FOF_TRANSLUCENT, NULL, blendmode);
 				else
-					HWR_SplitWall(gl_frontsector, wallVerts, gl_midtexture, &Surf, FF_CUTLEVEL, NULL, blendmode);
+					HWR_SplitWall(gl_frontsector, wallVerts, gl_midtexture, &Surf, FOF_CUTLEVEL, NULL, blendmode);
 			}
 			else if (!(blendmode & PF_Masked))
 				HWR_AddTransparentWall(wallVerts, &Surf, gl_midtexture, blendmode, false, lightnum, colormap);
@@ -1549,7 +1549,7 @@ static void HWR_ProcessSeg(void) // Sort of like GLWall::Process in GZDoom
 
 			// I don't think that solid walls can use translucent linedef types...
 			if (gl_frontsector->numlights)
-				HWR_SplitWall(gl_frontsector, wallVerts, gl_midtexture, &Surf, FF_CUTLEVEL, NULL, 0);
+				HWR_SplitWall(gl_frontsector, wallVerts, gl_midtexture, &Surf, FOF_CUTLEVEL, NULL, 0);
 			else
 			{
 				if (grTex->mipmap.flags & TF_TRANSPARENT)
@@ -1613,9 +1613,9 @@ static void HWR_ProcessSeg(void) // Sort of like GLWall::Process in GZDoom
 
 				if (bothsides) continue;
 
-				if (!(rover->flags & FF_EXISTS) || !(rover->flags & FF_RENDERSIDES))
+				if (!(rover->fofflags & FOF_EXISTS) || !(rover->fofflags & FOF_RENDERSIDES))
 					continue;
-				if (!(rover->flags & FF_ALLSIDES) && rover->flags & FF_INVERTSIDES)
+				if (!(rover->fofflags & FOF_ALLSIDES) && rover->fofflags & FOF_INVERTSIDES)
 					continue;
 
 				SLOPEPARAMS(*rover->t_slope, high1, highslope1, *rover->topheight)
@@ -1656,7 +1656,7 @@ static void HWR_ProcessSeg(void) // Sort of like GLWall::Process in GZDoom
 				wallVerts[2].y = FIXED_TO_FLOAT(hS);
 				wallVerts[0].y = FIXED_TO_FLOAT(l);
 				wallVerts[1].y = FIXED_TO_FLOAT(lS);
-				if (rover->flags & FF_FOG)
+				if (rover->fofflags & FOF_FOG)
 				{
 					wallVerts[3].t = wallVerts[2].t = 0;
 					wallVerts[0].t = wallVerts[1].t = 0;
@@ -1715,7 +1715,7 @@ static void HWR_ProcessSeg(void) // Sort of like GLWall::Process in GZDoom
 					wallVerts[0].s = wallVerts[3].s = cliplow * grTex->scaleX;
 					wallVerts[2].s = wallVerts[1].s = cliphigh * grTex->scaleX;
 				}
-				if (rover->flags & FF_FOG)
+				if (rover->fofflags & FOF_FOG)
 				{
 					FBITFIELD blendmode;
 
@@ -1727,7 +1727,7 @@ static void HWR_ProcessSeg(void) // Sort of like GLWall::Process in GZDoom
 					Surf.PolyColor.s.alpha = HWR_FogBlockAlpha(rover->master->frontsector->lightlevel, rover->master->frontsector->extra_colormap);
 
 					if (gl_frontsector->numlights)
-						HWR_SplitWall(gl_frontsector, wallVerts, 0, &Surf, rover->flags, rover, blendmode);
+						HWR_SplitWall(gl_frontsector, wallVerts, 0, &Surf, rover->fofflags, rover, blendmode);
 					else
 						HWR_AddTransparentWall(wallVerts, &Surf, 0, blendmode, true, lightnum, colormap);
 				}
@@ -1735,14 +1735,14 @@ static void HWR_ProcessSeg(void) // Sort of like GLWall::Process in GZDoom
 				{
 					FBITFIELD blendmode = PF_Masked;
 
-					if ((rover->flags & FF_TRANSLUCENT && rover->alpha < 256) || rover->blend)
+					if ((rover->fofflags & FOF_TRANSLUCENT && rover->alpha < 256) || rover->blend)
 					{
 						blendmode = rover->blend ? HWR_GetBlendModeFlag(rover->blend) : PF_Translucent;
 						Surf.PolyColor.s.alpha = (UINT8)rover->alpha-1 > 255 ? 255 : rover->alpha-1;
 					}
 
 					if (gl_frontsector->numlights)
-						HWR_SplitWall(gl_frontsector, wallVerts, texnum, &Surf, rover->flags, rover, blendmode);
+						HWR_SplitWall(gl_frontsector, wallVerts, texnum, &Surf, rover->fofflags, rover, blendmode);
 					else
 					{
 						if (blendmode != PF_Masked)
@@ -1770,9 +1770,9 @@ static void HWR_ProcessSeg(void) // Sort of like GLWall::Process in GZDoom
 
 				if (bothsides) continue;
 
-				if (!(rover->flags & FF_EXISTS) || !(rover->flags & FF_RENDERSIDES))
+				if (!(rover->fofflags & FOF_EXISTS) || !(rover->fofflags & FOF_RENDERSIDES))
 					continue;
-				if (!(rover->flags & FF_ALLSIDES || rover->flags & FF_INVERTSIDES))
+				if (!(rover->fofflags & FOF_ALLSIDES || rover->fofflags & FOF_INVERTSIDES))
 					continue;
 
 				SLOPEPARAMS(*rover->t_slope, high1, highslope1, *rover->topheight)
@@ -1812,7 +1812,7 @@ static void HWR_ProcessSeg(void) // Sort of like GLWall::Process in GZDoom
 				wallVerts[2].y = FIXED_TO_FLOAT(hS);
 				wallVerts[0].y = FIXED_TO_FLOAT(l);
 				wallVerts[1].y = FIXED_TO_FLOAT(lS);
-				if (rover->flags & FF_FOG)
+				if (rover->fofflags & FOF_FOG)
 				{
 					wallVerts[3].t = wallVerts[2].t = 0;
 					wallVerts[0].t = wallVerts[1].t = 0;
@@ -1838,7 +1838,7 @@ static void HWR_ProcessSeg(void) // Sort of like GLWall::Process in GZDoom
 					wallVerts[2].s = wallVerts[1].s = cliphigh * grTex->scaleX;
 				}
 
-				if (rover->flags & FF_FOG)
+				if (rover->fofflags & FOF_FOG)
 				{
 					FBITFIELD blendmode;
 
@@ -1850,7 +1850,7 @@ static void HWR_ProcessSeg(void) // Sort of like GLWall::Process in GZDoom
 					Surf.PolyColor.s.alpha = HWR_FogBlockAlpha(rover->master->frontsector->lightlevel, rover->master->frontsector->extra_colormap);
 
 					if (gl_backsector->numlights)
-						HWR_SplitWall(gl_backsector, wallVerts, 0, &Surf, rover->flags, rover, blendmode);
+						HWR_SplitWall(gl_backsector, wallVerts, 0, &Surf, rover->fofflags, rover, blendmode);
 					else
 						HWR_AddTransparentWall(wallVerts, &Surf, 0, blendmode, true, lightnum, colormap);
 				}
@@ -1858,14 +1858,14 @@ static void HWR_ProcessSeg(void) // Sort of like GLWall::Process in GZDoom
 				{
 					FBITFIELD blendmode = PF_Masked;
 
-					if ((rover->flags & FF_TRANSLUCENT && rover->alpha < 256) || rover->blend)
+					if ((rover->fofflags & FOF_TRANSLUCENT && rover->alpha < 256) || rover->blend)
 					{
 						blendmode = rover->blend ? HWR_GetBlendModeFlag(rover->blend) : PF_Translucent;
 						Surf.PolyColor.s.alpha = (UINT8)rover->alpha-1 > 255 ? 255 : rover->alpha-1;
 					}
 
 					if (gl_backsector->numlights)
-						HWR_SplitWall(gl_backsector, wallVerts, texnum, &Surf, rover->flags, rover, blendmode);
+						HWR_SplitWall(gl_backsector, wallVerts, texnum, &Surf, rover->fofflags, rover, blendmode);
 					else
 					{
 						if (blendmode != PF_Masked)
@@ -2946,7 +2946,7 @@ static FBITFIELD HWR_RippleBlend(sector_t *sector, ffloor_t *rover, boolean ceil
 {
 	(void)sector;
 	(void)ceiling;
-	return /*R_IsRipplePlane(sector, rover, ceiling)*/ (rover->flags & FF_RIPPLE) ? PF_Ripple : 0;
+	return /*R_IsRipplePlane(sector, rover, ceiling)*/ (rover->fofflags & FOF_RIPPLE) ? PF_Ripple : 0;
 }
 
 // -----------------+
@@ -3114,17 +3114,17 @@ static void HWR_Subsector(size_t num)
 			cullHeight   = P_GetFFloorBottomZAt(rover, viewx, viewy);
 			centerHeight = P_GetFFloorBottomZAt(rover, gl_frontsector->soundorg.x, gl_frontsector->soundorg.y);
 
-			if (!(rover->flags & FF_EXISTS) || !(rover->flags & FF_RENDERPLANES))
+			if (!(rover->fofflags & FOF_EXISTS) || !(rover->fofflags & FOF_RENDERPLANES))
 				continue;
 			if (sub->validcount == validcount)
 				continue;
 
 			if (centerHeight <= locCeilingHeight &&
 			    centerHeight >= locFloorHeight &&
-			    ((dup_viewz < cullHeight && (rover->flags & FF_BOTHPLANES || !(rover->flags & FF_INVERTPLANES))) ||
-			     (dup_viewz > cullHeight && (rover->flags & FF_BOTHPLANES || rover->flags & FF_INVERTPLANES))))
+			    ((dup_viewz < cullHeight && (rover->fofflags & FOF_BOTHPLANES || !(rover->fofflags & FOF_INVERTPLANES))) ||
+			     (dup_viewz > cullHeight && (rover->fofflags & FOF_BOTHPLANES || rover->fofflags & FOF_INVERTPLANES))))
 			{
-				if (rover->flags & FF_FOG)
+				if (rover->fofflags & FOF_FOG)
 				{
 					UINT8 alpha;
 
@@ -3139,7 +3139,7 @@ static void HWR_Subsector(size_t num)
 					                       alpha, rover->master->frontsector, PF_Fog|PF_NoTexture,
 										   true, rover->master->frontsector->extra_colormap);
 				}
-				else if ((rover->flags & FF_TRANSLUCENT && rover->alpha < 256) || rover->blend) // SoM: Flags are more efficient
+				else if ((rover->fofflags & FOF_TRANSLUCENT && rover->alpha < 256) || rover->blend) // SoM: Flags are more efficient
 				{
 					light = R_GetPlaneLight(gl_frontsector, centerHeight, dup_viewz < cullHeight ? true : false);
 
@@ -3167,10 +3167,10 @@ static void HWR_Subsector(size_t num)
 
 			if (centerHeight >= locFloorHeight &&
 			    centerHeight <= locCeilingHeight &&
-			    ((dup_viewz > cullHeight && (rover->flags & FF_BOTHPLANES || !(rover->flags & FF_INVERTPLANES))) ||
-			     (dup_viewz < cullHeight && (rover->flags & FF_BOTHPLANES || rover->flags & FF_INVERTPLANES))))
+			    ((dup_viewz > cullHeight && (rover->fofflags & FOF_BOTHPLANES || !(rover->fofflags & FOF_INVERTPLANES))) ||
+			     (dup_viewz < cullHeight && (rover->fofflags & FOF_BOTHPLANES || rover->fofflags & FOF_INVERTPLANES))))
 			{
-				if (rover->flags & FF_FOG)
+				if (rover->fofflags & FOF_FOG)
 				{
 					UINT8 alpha;
 
@@ -3185,7 +3185,7 @@ static void HWR_Subsector(size_t num)
 					                       alpha, rover->master->frontsector, PF_Fog|PF_NoTexture,
 										   true, rover->master->frontsector->extra_colormap);
 				}
-				else if ((rover->flags & FF_TRANSLUCENT && rover->alpha < 256) || rover->blend)
+				else if ((rover->fofflags & FOF_TRANSLUCENT && rover->alpha < 256) || rover->blend)
 				{
 					light = R_GetPlaneLight(gl_frontsector, centerHeight, dup_viewz < cullHeight ? true : false);
 
@@ -3939,7 +3939,7 @@ static void HWR_SplitSprite(gl_vissprite_t *spr)
 			return;
 
 		// even if we aren't changing colormap or lightlevel, we still need to continue drawing down the sprite
-		if (!(list[i].flags & FF_NOSHADE) && (list[i].flags & FF_CUTSPRITES))
+		if (!(list[i].flags & FOF_NOSHADE) && (list[i].flags & FOF_CUTSPRITES))
 		{
 			if (!lightset)
 				lightlevel = *list[i].lightlevel > 255 ? 255 : *list[i].lightlevel;
diff --git a/src/lua_maplib.c b/src/lua_maplib.c
index 0c3440426fe1f27c0790490b36430541911b1ff5..b4565121d34dc2092632aa5e146de128a96cfcd5 100644
--- a/src/lua_maplib.c
+++ b/src/lua_maplib.c
@@ -214,6 +214,7 @@ enum ffloor_e {
 	ffloor_tslope,
 	ffloor_bslope,
 	ffloor_sector,
+	ffloor_fofflags,
 	ffloor_flags,
 	ffloor_master,
 	ffloor_target,
@@ -239,6 +240,7 @@ static const char *const ffloor_opt[] = {
 	"t_slope",
 	"b_slope",
 	"sector", // secnum pushed as control sector userdata
+	"fofflags",
 	"flags",
 	"master", // control linedef
 	"target", // target sector
@@ -1841,6 +1843,80 @@ static int lib_numnodes(lua_State *L)
 // ffloor_t //
 //////////////
 
+static INT32 P_GetOldFOFFlags(ffloor_t *fflr)
+{
+	INT32 result = 0;
+	if (fflr->fofflags & FOF_EXISTS)
+		result |= FF_OLD_EXISTS;
+	if (fflr->fofflags & FOF_BLOCKPLAYER)
+		result |= FF_OLD_BLOCKPLAYER;
+	if (fflr->fofflags & FOF_BLOCKOTHERS)
+		result |= FF_OLD_BLOCKOTHERS;
+	if (fflr->fofflags & FOF_RENDERSIDES)
+		result |= FF_OLD_RENDERSIDES;
+	if (fflr->fofflags & FOF_RENDERPLANES)
+		result |= FF_OLD_RENDERPLANES;
+	if (fflr->fofflags & FOF_SWIMMABLE)
+		result |= FF_OLD_SWIMMABLE;
+	if (fflr->fofflags & FOF_NOSHADE)
+		result |= FF_OLD_NOSHADE;
+	if (fflr->fofflags & FOF_CUTSOLIDS)
+		result |= FF_OLD_CUTSOLIDS;
+	if (fflr->fofflags & FOF_CUTEXTRA)
+		result |= FF_OLD_CUTEXTRA;
+	if (fflr->fofflags & FOF_CUTSPRITES)
+		result |= FF_OLD_CUTSPRITES;
+	if (fflr->fofflags & FOF_BOTHPLANES)
+		result |= FF_OLD_BOTHPLANES;
+	if (fflr->fofflags & FOF_EXTRA)
+		result |= FF_OLD_EXTRA;
+	if (fflr->fofflags & FOF_TRANSLUCENT)
+		result |= FF_OLD_TRANSLUCENT;
+	if (fflr->fofflags & FOF_FOG)
+		result |= FF_OLD_FOG;
+	if (fflr->fofflags & FOF_INVERTPLANES)
+		result |= FF_OLD_INVERTPLANES;
+	if (fflr->fofflags & FOF_ALLSIDES)
+		result |= FF_OLD_ALLSIDES;
+	if (fflr->fofflags & FOF_INVERTSIDES)
+		result |= FF_OLD_INVERTSIDES;
+	if (fflr->fofflags & FOF_DOUBLESHADOW)
+		result |= FF_OLD_DOUBLESHADOW;
+	if (fflr->fofflags & FOF_FLOATBOB)
+		result |= FF_OLD_FLOATBOB;
+	if (fflr->fofflags & FOF_NORETURN)
+		result |= FF_OLD_NORETURN;
+	if (fflr->fofflags & FOF_CRUMBLE)
+		result |= FF_OLD_CRUMBLE;
+	if (fflr->bustflags & FB_ONLYBOTTOM)
+		result |= FF_OLD_SHATTERBOTTOM;
+	if (fflr->fofflags & FOF_GOOWATER)
+		result |= FF_OLD_GOOWATER;
+	if (fflr->fofflags & FOF_MARIO)
+		result |= FF_OLD_MARIO;
+	if (fflr->fofflags & FOF_BUSTUP)
+		result |= FF_OLD_BUSTUP;
+	if (fflr->fofflags & FOF_QUICKSAND)
+		result |= FF_OLD_QUICKSAND;
+	if (fflr->fofflags & FOF_PLATFORM)
+		result |= FF_OLD_PLATFORM;
+	if (fflr->fofflags & FOF_REVERSEPLATFORM)
+		result |= FF_OLD_REVERSEPLATFORM;
+	if (fflr->fofflags & FOF_INTANGIBLEFLATS)
+		result |= FF_OLD_INTANGIBLEFLATS;
+	if (fflr->busttype == BT_TOUCH)
+		result |= FF_OLD_SHATTER;
+	if (fflr->busttype == BT_SPINBUST)
+		result |= FF_OLD_SPINBUST;
+	if (fflr->busttype == BT_STRONG)
+		result |= FF_OLD_STRONGBUST;
+	if (fflr->fofflags & FF_OLD_RIPPLE)
+		result |= FOF_RIPPLE;
+	if (fflr->fofflags & FF_OLD_COLORMAPONLY)
+		result |= FOF_COLORMAPONLY;
+	return result;
+}
+
 static int ffloor_get(lua_State *L)
 {
 	ffloor_t *ffloor = *((ffloor_t **)luaL_checkudata(L, 1, META_FFLOOR));
@@ -1895,8 +1971,11 @@ static int ffloor_get(lua_State *L)
 	case ffloor_sector:
 		LUA_PushUserdata(L, &sectors[ffloor->secnum], META_SECTOR);
 		return 1;
+	case ffloor_fofflags:
+		lua_pushinteger(L, ffloor->fofflags);
+		return 1;
 	case ffloor_flags:
-		lua_pushinteger(L, ffloor->flags);
+		lua_pushinteger(L, P_GetOldFOFFlags(ffloor));
 		return 1;
 	case ffloor_master:
 		LUA_PushUserdata(L, ffloor->master, META_LINE);
@@ -1938,6 +2017,88 @@ static int ffloor_get(lua_State *L)
 	return 0;
 }
 
+static void P_SetOldFOFFlags(ffloor_t *fflr, oldffloortype_e oldflags)
+{
+	ffloortype_e originalflags = fflr->fofflags;
+	fflr->fofflags = 0;
+	if (oldflags & FF_OLD_EXISTS)
+		fflr->fofflags |= FOF_EXISTS;
+	if (oldflags & FF_OLD_BLOCKPLAYER)
+		fflr->fofflags |= FOF_BLOCKPLAYER;
+	if (oldflags & FF_OLD_BLOCKOTHERS)
+		fflr->fofflags |= FOF_BLOCKOTHERS;
+	if (oldflags & FF_OLD_RENDERSIDES)
+		fflr->fofflags |= FOF_RENDERSIDES;
+	if (oldflags & FF_OLD_RENDERPLANES)
+		fflr->fofflags |= FOF_RENDERPLANES;
+	if (oldflags & FF_OLD_SWIMMABLE)
+		fflr->fofflags |= FOF_SWIMMABLE;
+	if (oldflags & FF_OLD_NOSHADE)
+		fflr->fofflags |= FOF_NOSHADE;
+	if (oldflags & FF_OLD_CUTSOLIDS)
+		fflr->fofflags |= FOF_CUTSOLIDS;
+	if (oldflags & FF_OLD_CUTEXTRA)
+		fflr->fofflags |= FOF_CUTEXTRA;
+	if (oldflags & FF_OLD_CUTSPRITES)
+		fflr->fofflags |= FOF_CUTSPRITES;
+	if (oldflags & FF_OLD_BOTHPLANES)
+		fflr->fofflags |= FOF_BOTHPLANES;
+	if (oldflags & FF_OLD_EXTRA)
+		fflr->fofflags |= FOF_EXTRA;
+	if (oldflags & FF_OLD_TRANSLUCENT)
+		fflr->fofflags |= FOF_TRANSLUCENT;
+	if (oldflags & FF_OLD_FOG)
+		fflr->fofflags |= FOF_FOG;
+	if (oldflags & FF_OLD_INVERTPLANES)
+		fflr->fofflags |= FOF_INVERTPLANES;
+	if (oldflags & FF_OLD_ALLSIDES)
+		fflr->fofflags |= FOF_ALLSIDES;
+	if (oldflags & FF_OLD_INVERTSIDES)
+		fflr->fofflags |= FOF_INVERTSIDES;
+	if (oldflags & FF_OLD_DOUBLESHADOW)
+		fflr->fofflags |= FOF_DOUBLESHADOW;
+	if (oldflags & FF_OLD_FLOATBOB)
+		fflr->fofflags |= FOF_FLOATBOB;
+	if (oldflags & FF_OLD_NORETURN)
+		fflr->fofflags |= FOF_NORETURN;
+	if (oldflags & FF_OLD_CRUMBLE)
+		fflr->fofflags |= FOF_CRUMBLE;
+	if (oldflags & FF_OLD_GOOWATER)
+		fflr->fofflags |= FOF_GOOWATER;
+	if (oldflags & FF_OLD_MARIO)
+		fflr->fofflags |= FOF_MARIO;
+	if (oldflags & FF_OLD_BUSTUP)
+		fflr->fofflags |= FOF_BUSTUP;
+	if (oldflags & FF_OLD_QUICKSAND)
+		fflr->fofflags |= FOF_QUICKSAND;
+	if (oldflags & FF_OLD_PLATFORM)
+		fflr->fofflags |= FOF_PLATFORM;
+	if (oldflags & FF_OLD_REVERSEPLATFORM)
+		fflr->fofflags |= FOF_REVERSEPLATFORM;
+	if (oldflags & FF_OLD_RIPPLE)
+		fflr->fofflags |= FOF_RIPPLE;
+	if (oldflags & FF_OLD_COLORMAPONLY)
+		fflr->fofflags |= FOF_COLORMAPONLY;
+	if (originalflags & FOF_BOUNCY)
+		fflr->fofflags |= FOF_BOUNCY;
+	if (originalflags & FOF_SPLAT)
+		fflr->fofflags |= FOF_SPLAT;
+
+	if (oldflags & FF_OLD_SHATTER)
+		fflr->busttype = BT_TOUCH;
+	else if (oldflags & FF_OLD_SPINBUST)
+		fflr->busttype = BT_SPINBUST;
+	else if (oldflags & FF_OLD_STRONGBUST)
+		fflr->busttype = BT_STRONG;
+	else
+		fflr->busttype = BT_REGULAR;
+
+	if (oldflags & FF_OLD_SHATTERBOTTOM)
+		fflr->bustflags |= FB_ONLYBOTTOM;
+	else
+		fflr->bustflags &= ~FB_ONLYBOTTOM;
+}
+
 static int ffloor_set(lua_State *L)
 {
 	ffloor_t *ffloor = *((ffloor_t **)luaL_checkudata(L, 1, META_FFLOOR));
@@ -2002,10 +2163,20 @@ static int ffloor_set(lua_State *L)
 	case ffloor_bottompic:
 		*ffloor->bottompic = P_AddLevelFlatRuntime(luaL_checkstring(L, 3));
 		break;
+	case ffloor_fofflags: {
+		ffloortype_e oldflags = ffloor->fofflags; // store FOF's old flags
+		ffloor->fofflags = luaL_checkinteger(L, 3);
+		if (ffloor->fofflags != oldflags)
+			ffloor->target->moved = true; // reset target sector's lightlist
+		break;
+	}
 	case ffloor_flags: {
-		ffloortype_e oldflags = ffloor->flags; // store FOF's old flags
-		ffloor->flags = luaL_checkinteger(L, 3);
-		if (ffloor->flags != oldflags)
+		ffloortype_e oldflags = ffloor->fofflags; // store FOF's old flags
+		busttype_e oldbusttype = ffloor->busttype;
+		ffloorbustflags_e oldbustflags = ffloor->bustflags;
+		oldffloortype_e newflags = luaL_checkinteger(L, 3);
+		P_SetOldFOFFlags(ffloor, newflags);
+		if (ffloor->fofflags != oldflags || ffloor->busttype != oldbusttype || ffloor->bustflags != oldbustflags)
 			ffloor->target->moved = true; // reset target sector's lightlist
 		break;
 	}
diff --git a/src/p_enemy.c b/src/p_enemy.c
index 75590faaaf35e36accf30681f06763966be96a95..4c36446af3826d65e83a5240b63d917d196fad8b 100644
--- a/src/p_enemy.c
+++ b/src/p_enemy.c
@@ -498,7 +498,7 @@ static boolean P_WaterInSector(mobj_t *mobj, fixed_t x, fixed_t y)
 
 		for (rover = sector->ffloors; rover; rover = rover->next)
 		{
-			if (!(rover->flags & FF_EXISTS) || !(rover->flags & FF_SWIMMABLE))
+			if (!(rover->fofflags & FOF_EXISTS) || !(rover->fofflags & FOF_SWIMMABLE))
 				continue;
 
 			if (*rover->topheight >= mobj->floorz && *rover->topheight <= mobj->z)
diff --git a/src/p_floor.c b/src/p_floor.c
index b65435c21a745b0fa9fd5ed22c0906d344f94d85..d9e0ee0f267722c4055cdbc133b7face082090fd 100644
--- a/src/p_floor.c
+++ b/src/p_floor.c
@@ -551,7 +551,7 @@ static fixed_t P_SectorCheckWater(sector_t *analyzesector,
 
 		for (rover = analyzesector->ffloors; rover; rover = rover->next)
 		{
-			if (!(rover->flags & FF_EXISTS) || !(rover->flags & FF_SWIMMABLE) || rover->flags & FF_SOLID)
+			if (!(rover->fofflags & FOF_EXISTS) || !(rover->fofflags & FOF_SWIMMABLE) || rover->fofflags & FOF_SOLID)
 				continue;
 
 			// If the sector is below the water, don't bother.
@@ -757,10 +757,10 @@ void T_StartCrumble(crumble_t *crumble)
 
 				for (rover = sector->ffloors; rover; rover = rover->next)
 				{
-					if (!(rover->flags & FF_CRUMBLE))
+					if (!(rover->fofflags & FOF_CRUMBLE))
 						continue;
 
-					if (!(rover->flags & FF_FLOATBOB))
+					if (!(rover->fofflags & FOF_FLOATBOB))
 						continue;
 
 					if (rover->master != crumble->sourceline)
@@ -769,7 +769,7 @@ void T_StartCrumble(crumble_t *crumble)
 					rover->alpha = crumble->origalpha;
 
 					if (rover->alpha == 0xff)
-						rover->flags &= ~FF_TRANSLUCENT;
+						rover->fofflags &= ~FOF_TRANSLUCENT;
 				}
 			}
 
@@ -793,13 +793,13 @@ void T_StartCrumble(crumble_t *crumble)
 
 				for (rover = sector->ffloors; rover; rover = rover->next)
 				{
-					if (rover->flags & FF_NORETURN)
+					if (rover->fofflags & FOF_NORETURN)
 						continue;
 
-					if (!(rover->flags & FF_CRUMBLE))
+					if (!(rover->fofflags & FOF_CRUMBLE))
 						continue;
 
-					if (!(rover->flags & FF_FLOATBOB))
+					if (!(rover->fofflags & FOF_FLOATBOB))
 						continue;
 
 					if (rover->master != crumble->sourceline)
@@ -807,7 +807,7 @@ void T_StartCrumble(crumble_t *crumble)
 
 					if (rover->alpha == crumble->origalpha)
 					{
-						rover->flags |= FF_TRANSLUCENT;
+						rover->fofflags |= FOF_TRANSLUCENT;
 						rover->alpha = 0x00;
 					}
 					else
@@ -815,7 +815,7 @@ void T_StartCrumble(crumble_t *crumble)
 						rover->alpha = crumble->origalpha;
 
 						if (rover->alpha == 0xff)
-							rover->flags &= ~FF_TRANSLUCENT;
+							rover->fofflags &= ~FOF_TRANSLUCENT;
 					}
 				}
 			}
@@ -1082,7 +1082,7 @@ void T_ThwompSector(thwomp_t *thwomp)
 
 	if (thwomp->direction == 0) // Not going anywhere, so look for players.
 	{
-		if (rover->flags & FF_EXISTS)
+		if (rover->fofflags & FOF_EXISTS)
 		{
 			UINT8 i;
 			// scan the players to find victims!
@@ -1175,7 +1175,7 @@ void T_ThwompSector(thwomp_t *thwomp)
 
 			if (res == pastdest)
 			{
-				if (rover->flags & FF_EXISTS)
+				if (rover->fofflags & FOF_EXISTS)
 					S_StartSound((void *)&actionsector->soundorg, thwomp->sound);
 
 				thwomp->direction = 1; // start heading back up
@@ -1928,7 +1928,7 @@ void EV_CrumbleChain(sector_t *sec, ffloor_t *rover)
 	}
 
 	// no longer exists (can't collide with again)
-	rover->flags &= ~FF_EXISTS;
+	rover->fofflags &= ~FOF_EXISTS;
 	rover->master->frontsector->moved = true;
 	P_RecalcPrecipInSector(sec);
 }
@@ -2054,8 +2054,8 @@ void EV_MarioBlock(ffloor_t *rover, sector_t *sector, mobj_t *puncher)
 	if (roversec->floordata || roversec->ceilingdata)
 		return;
 
-	if (!(rover->flags & FF_SOLID))
-		rover->flags |= (FF_SOLID|FF_RENDERALL|FF_CUTLEVEL);
+	if (!(rover->fofflags & FOF_SOLID))
+		rover->fofflags |= (FOF_SOLID|FOF_RENDERALL|FOF_CUTLEVEL);
 
 	// Find an item to pop out!
 	thing = SearchMarioNode(roversec->touching_thinglist);
diff --git a/src/p_map.c b/src/p_map.c
index aee13ae7e03501f468f21ca4273d3a3befdded3d..1a8494deafadbeb6ffb7d76069b9fd1c9526a280 100644
--- a/src/p_map.c
+++ b/src/p_map.c
@@ -2073,13 +2073,13 @@ boolean P_CheckPosition(mobj_t *thing, fixed_t x, fixed_t y)
 		{
 			fixed_t topheight, bottomheight;
 
-			if (!(rover->flags & FF_EXISTS))
+			if (!(rover->fofflags & FOF_EXISTS))
 				continue;
 
 			topheight = P_GetFOFTopZ(thing, newsubsec->sector, rover, x, y, NULL);
 			bottomheight = P_GetFOFBottomZ(thing, newsubsec->sector, rover, x, y, NULL);
 
-			if ((rover->flags & (FF_SWIMMABLE|FF_GOOWATER)) == (FF_SWIMMABLE|FF_GOOWATER) && !(thing->flags & MF_NOGRAVITY))
+			if ((rover->fofflags & (FOF_SWIMMABLE|FOF_GOOWATER)) == (FOF_SWIMMABLE|FOF_GOOWATER) && !(thing->flags & MF_NOGRAVITY))
 			{
 				// If you're inside goowater and slowing down
 				fixed_t sinklevel = FixedMul(thing->info->height/6, thing->scale);
@@ -2118,14 +2118,14 @@ boolean P_CheckPosition(mobj_t *thing, fixed_t x, fixed_t y)
 
 			if (thing->player && (P_CheckSolidLava(rover) || P_CanRunOnWater(thing->player, rover)))
 				;
-			else if (thing->type == MT_SKIM && (rover->flags & FF_SWIMMABLE))
+			else if (thing->type == MT_SKIM && (rover->fofflags & FOF_SWIMMABLE))
 				;
-			else if (!((rover->flags & FF_BLOCKPLAYER && thing->player)
-			    || (rover->flags & FF_BLOCKOTHERS && !thing->player)
-				|| rover->flags & FF_QUICKSAND))
+			else if (!((rover->fofflags & FOF_BLOCKPLAYER && thing->player)
+			    || (rover->fofflags & FOF_BLOCKOTHERS && !thing->player)
+				|| rover->fofflags & FOF_QUICKSAND))
 				continue;
 
-			if (rover->flags & FF_QUICKSAND)
+			if (rover->fofflags & FOF_QUICKSAND)
 			{
 				if (thing->z < topheight && bottomheight < thingtop)
 				{
@@ -2145,15 +2145,15 @@ boolean P_CheckPosition(mobj_t *thing, fixed_t x, fixed_t y)
 				+ ((topheight - bottomheight)/2));
 
 			if (topheight > tmfloorz && abs(delta1) < abs(delta2)
-				&& !(rover->flags & FF_REVERSEPLATFORM))
+				&& !(rover->fofflags & FOF_REVERSEPLATFORM))
 			{
 				tmfloorz = tmdropoffz = topheight;
 				tmfloorrover = rover;
 				tmfloorslope = *rover->t_slope;
 			}
 			if (bottomheight < tmceilingz && abs(delta1) >= abs(delta2)
-				&& !(rover->flags & FF_PLATFORM)
-				&& !(thing->type == MT_SKIM && (rover->flags & FF_SWIMMABLE)))
+				&& !(rover->fofflags & FOF_PLATFORM)
+				&& !(thing->type == MT_SKIM && (rover->fofflags & FOF_SWIMMABLE)))
 			{
 				tmceilingz = tmdrpoffceilz = bottomheight;
 				tmceilingrover = rover;
@@ -2371,7 +2371,7 @@ boolean P_CheckCameraPosition(fixed_t x, fixed_t y, camera_t *thiscam)
 		for (rover = newsubsec->sector->ffloors; rover; rover = rover->next)
 		{
 			fixed_t topheight, bottomheight;
-			if (!(rover->flags & FF_BLOCKOTHERS) || !(rover->flags & FF_EXISTS) || !(rover->flags & FF_RENDERALL) || (rover->master->frontsector->flags & MSF_NOCLIPCAMERA))
+			if (!(rover->fofflags & FOF_BLOCKOTHERS) || !(rover->fofflags & FOF_EXISTS) || !(rover->fofflags & FOF_RENDERALL) || (rover->master->frontsector->flags & MSF_NOCLIPCAMERA))
 				continue;
 
 			topheight = P_CameraGetFOFTopZ(thiscam, newsubsec->sector, rover, x, y, NULL);
@@ -3024,9 +3024,9 @@ static boolean P_ThingHeightClip(mobj_t *thing)
 	{
 		rover = (thing->eflags & MFE_VERTICALFLIP) ? oldceilingrover : oldfloorrover;
 
-		// Match the Thing's old floorz to an FOF and check for FF_EXISTS
-		// If ~FF_EXISTS, don't set mobj Z.
-		if (!rover || ((rover->flags & FF_EXISTS) && (rover->flags & FF_SOLID)))
+		// Match the Thing's old floorz to an FOF and check for FOF_EXISTS
+		// If ~FOF_EXISTS, don't set mobj Z.
+		if (!rover || ((rover->fofflags & FOF_EXISTS) && (rover->fofflags & FOF_SOLID)))
 		{
 			hitfloor = bouncing;
 			if (thing->eflags & MFE_VERTICALFLIP)
@@ -3287,7 +3287,7 @@ static boolean P_IsClimbingValid(player_t *player, angle_t angle)
 
 		for (rover = glidesector->ffloors; rover; rover = rover->next)
 		{
-			if (!(rover->flags & FF_EXISTS) || !(rover->flags & FF_BLOCKPLAYER))
+			if (!(rover->fofflags & FOF_EXISTS) || !(rover->fofflags & FOF_BLOCKPLAYER))
 				continue;
 
 			topheight    = P_GetFFloorTopZAt   (rover, mo->x, mo->y);
@@ -3403,7 +3403,7 @@ static void PTR_GlideClimbTraverse(line_t *li)
 	{
 		for (rover = checksector->ffloors; rover; rover = rover->next)
 		{
-			if (!(rover->flags & FF_EXISTS) || !(rover->flags & FF_BLOCKPLAYER) || ((rover->flags & FF_BUSTUP) && (slidemo->player->charflags & SF_CANBUSTWALLS)))
+			if (!(rover->fofflags & FOF_EXISTS) || !(rover->fofflags & FOF_BLOCKPLAYER) || ((rover->fofflags & FOF_BUSTUP) && (slidemo->player->charflags & SF_CANBUSTWALLS)))
 				continue;
 
 			topheight    = P_GetFFloorTopZAt   (rover, slidemo->x, slidemo->y);
@@ -3631,10 +3631,10 @@ static void P_CheckLavaWall(mobj_t *mo, sector_t *sec)
 
 	for (rover = sec->ffloors; rover; rover = rover->next)
 	{
-		if (!(rover->flags & FF_EXISTS))
+		if (!(rover->fofflags & FOF_EXISTS))
 			continue;
 
-		if (!(rover->flags & FF_SWIMMABLE))
+		if (!(rover->fofflags & FOF_SWIMMABLE))
 			continue;
 
 		if (rover->master->frontsector->damagetype != SD_LAVA)
@@ -4241,8 +4241,8 @@ static boolean PIT_ChangeSector(mobj_t *thing, boolean realcrush)
 
 			for (rover = thing->subsector->sector->ffloors; rover; rover = rover->next)
 			{
-				if (!(((rover->flags & FF_BLOCKPLAYER) && thing->player)
-				|| ((rover->flags & FF_BLOCKOTHERS) && !thing->player)) || !(rover->flags & FF_EXISTS))
+				if (!(((rover->fofflags & FOF_BLOCKPLAYER) && thing->player)
+				|| ((rover->fofflags & FOF_BLOCKOTHERS) && !thing->player)) || !(rover->fofflags & FOF_EXISTS))
 					continue;
 
 				topheight = *rover->topheight;
@@ -5036,16 +5036,16 @@ fixed_t P_FloorzAtPos(fixed_t x, fixed_t y, fixed_t z, fixed_t height)
 		for (rover = sec->ffloors; rover; rover = rover->next)
 		{
 			fixed_t topheight, bottomheight;
-			if (!(rover->flags & FF_EXISTS))
+			if (!(rover->fofflags & FOF_EXISTS))
 				continue;
 
-			if ((!(rover->flags & FF_SOLID || rover->flags & FF_QUICKSAND) || (rover->flags & FF_SWIMMABLE)))
+			if ((!(rover->fofflags & FOF_SOLID || rover->fofflags & FOF_QUICKSAND) || (rover->fofflags & FOF_SWIMMABLE)))
 				continue;
 
 			topheight    = P_GetFFloorTopZAt   (rover, x, y);
 			bottomheight = P_GetFFloorBottomZAt(rover, x, y);
 
-			if (rover->flags & FF_QUICKSAND)
+			if (rover->fofflags & FOF_QUICKSAND)
 			{
 				if (z < topheight && bottomheight < thingtop)
 				{
@@ -5080,16 +5080,16 @@ fixed_t P_CeilingzAtPos(fixed_t x, fixed_t y, fixed_t z, fixed_t height)
 		for (rover = sec->ffloors; rover; rover = rover->next)
 		{
 			fixed_t topheight, bottomheight;
-			if (!(rover->flags & FF_EXISTS))
+			if (!(rover->fofflags & FOF_EXISTS))
 				continue;
 
-			if ((!(rover->flags & FF_SOLID || rover->flags & FF_QUICKSAND) || (rover->flags & FF_SWIMMABLE)))
+			if ((!(rover->fofflags & FOF_SOLID || rover->fofflags & FOF_QUICKSAND) || (rover->fofflags & FOF_SWIMMABLE)))
 				continue;
 
 			topheight    = P_GetFFloorTopZAt   (rover, x, y);
 			bottomheight = P_GetFFloorBottomZAt(rover, x, y);
 
-			if (rover->flags & FF_QUICKSAND)
+			if (rover->fofflags & FOF_QUICKSAND)
 			{
 				if (thingtop > bottomheight && topheight > z)
 				{
diff --git a/src/p_maputl.c b/src/p_maputl.c
index 614db93e36883982331a45ae819c09ce2f5777ca..260bcc0745a60394e65e7142eb529c5e0aa2619a 100644
--- a/src/p_maputl.c
+++ b/src/p_maputl.c
@@ -374,7 +374,7 @@ void P_CameraLineOpening(line_t *linedef)
 				for (rover = front->ffloors; rover; rover = rover->next)
 				{
 					fixed_t topheight, bottomheight;
-					if (!(rover->flags & FF_BLOCKOTHERS) || !(rover->flags & FF_RENDERALL) || !(rover->flags & FF_EXISTS) || (rover->master->frontsector->flags & MSF_NOCLIPCAMERA))
+					if (!(rover->fofflags & FOF_BLOCKOTHERS) || !(rover->fofflags & FOF_RENDERALL) || !(rover->fofflags & FOF_EXISTS) || (rover->master->frontsector->flags & MSF_NOCLIPCAMERA))
 						continue;
 
 					topheight = P_CameraGetFOFTopZ(mapcampointer, front, rover, tmx, tmy, linedef);
@@ -398,7 +398,7 @@ void P_CameraLineOpening(line_t *linedef)
 				for (rover = back->ffloors; rover; rover = rover->next)
 				{
 					fixed_t topheight, bottomheight;
-					if (!(rover->flags & FF_BLOCKOTHERS) || !(rover->flags & FF_RENDERALL) || !(rover->flags & FF_EXISTS) || (rover->master->frontsector->flags & MSF_NOCLIPCAMERA))
+					if (!(rover->fofflags & FOF_BLOCKOTHERS) || !(rover->fofflags & FOF_RENDERALL) || !(rover->fofflags & FOF_EXISTS) || (rover->master->frontsector->flags & MSF_NOCLIPCAMERA))
 						continue;
 
 					topheight = P_CameraGetFOFTopZ(mapcampointer, back, rover, tmx, tmy, linedef);
@@ -594,13 +594,13 @@ void P_LineOpening(line_t *linedef, mobj_t *mobj)
 				for (rover = front->ffloors; rover; rover = rover->next)
 				{
 					fixed_t topheight, bottomheight;
-					if (!(rover->flags & FF_EXISTS))
+					if (!(rover->fofflags & FOF_EXISTS))
 						continue;
 
 					if (mobj->player && (P_CheckSolidLava(rover) || P_CanRunOnWater(mobj->player, rover)))
 						;
-					else if (!((rover->flags & FF_BLOCKPLAYER && mobj->player)
-						|| (rover->flags & FF_BLOCKOTHERS && !mobj->player)))
+					else if (!((rover->fofflags & FOF_BLOCKPLAYER && mobj->player)
+						|| (rover->fofflags & FOF_BLOCKOTHERS && !mobj->player)))
 						continue;
 
 					topheight = P_GetFOFTopZ(mobj, front, rover, tmx, tmy, linedef);
@@ -609,7 +609,7 @@ void P_LineOpening(line_t *linedef, mobj_t *mobj)
 					delta1 = abs(mobj->z - (bottomheight + ((topheight - bottomheight)/2)));
 					delta2 = abs(thingtop - (bottomheight + ((topheight - bottomheight)/2)));
 
-					if (delta1 >= delta2 && (rover->flags & FF_INTANGIBLEFLATS) != FF_PLATFORM) // thing is below FOF
+					if (delta1 >= delta2 && (rover->fofflags & FOF_INTANGIBLEFLATS) != FOF_PLATFORM) // thing is below FOF
 					{
 						if (bottomheight < opentop) {
 							opentop = bottomheight;
@@ -620,7 +620,7 @@ void P_LineOpening(line_t *linedef, mobj_t *mobj)
 							highceiling = bottomheight;
 					}
 
-					if (delta1 < delta2 && (rover->flags & FF_INTANGIBLEFLATS) != FF_REVERSEPLATFORM) // thing is above FOF
+					if (delta1 < delta2 && (rover->fofflags & FOF_INTANGIBLEFLATS) != FOF_REVERSEPLATFORM) // thing is above FOF
 					{
 						if (topheight > openbottom) {
 							openbottom = topheight;
@@ -636,13 +636,13 @@ void P_LineOpening(line_t *linedef, mobj_t *mobj)
 				for (rover = back->ffloors; rover; rover = rover->next)
 				{
 					fixed_t topheight, bottomheight;
-					if (!(rover->flags & FF_EXISTS))
+					if (!(rover->fofflags & FOF_EXISTS))
 						continue;
 
 					if (mobj->player && (P_CheckSolidLava(rover) || P_CanRunOnWater(mobj->player, rover)))
 						;
-					else if (!((rover->flags & FF_BLOCKPLAYER && mobj->player)
-						|| (rover->flags & FF_BLOCKOTHERS && !mobj->player)))
+					else if (!((rover->fofflags & FOF_BLOCKPLAYER && mobj->player)
+						|| (rover->fofflags & FOF_BLOCKOTHERS && !mobj->player)))
 						continue;
 
 					topheight = P_GetFOFTopZ(mobj, back, rover, tmx, tmy, linedef);
@@ -651,7 +651,7 @@ void P_LineOpening(line_t *linedef, mobj_t *mobj)
 					delta1 = abs(mobj->z - (bottomheight + ((topheight - bottomheight)/2)));
 					delta2 = abs(thingtop - (bottomheight + ((topheight - bottomheight)/2)));
 
-					if (delta1 >= delta2 && (rover->flags & FF_INTANGIBLEFLATS) != FF_PLATFORM) // thing is below FOF
+					if (delta1 >= delta2 && (rover->fofflags & FOF_INTANGIBLEFLATS) != FOF_PLATFORM) // thing is below FOF
 					{
 						if (bottomheight < opentop) {
 							opentop = bottomheight;
@@ -662,7 +662,7 @@ void P_LineOpening(line_t *linedef, mobj_t *mobj)
 							highceiling = bottomheight;
 					}
 
-					if (delta1 < delta2 && (rover->flags & FF_INTANGIBLEFLATS) != FF_REVERSEPLATFORM) // thing is above FOF
+					if (delta1 < delta2 && (rover->fofflags & FOF_INTANGIBLEFLATS) != FOF_REVERSEPLATFORM) // thing is above FOF
 					{
 						if (topheight > openbottom) {
 							openbottom = topheight;
diff --git a/src/p_mobj.c b/src/p_mobj.c
index 36253569b96b0a21d4e670721d9f136e7b5c9296..3cc3dc338e88a7165489b0008cb58a6245aaf4d0 100644
--- a/src/p_mobj.c
+++ b/src/p_mobj.c
@@ -955,11 +955,11 @@ void P_ExplodeMissile(mobj_t *mo)
 boolean P_InsideANonSolidFFloor(mobj_t *mobj, ffloor_t *rover)
 {
 	fixed_t topheight, bottomheight;
-	if (!(rover->flags & FF_EXISTS))
+	if (!(rover->fofflags & FOF_EXISTS))
 		return false;
 
-	if ((((rover->flags & FF_BLOCKPLAYER) && mobj->player)
-		|| ((rover->flags & FF_BLOCKOTHERS) && !mobj->player)))
+	if ((((rover->fofflags & FOF_BLOCKPLAYER) && mobj->player)
+		|| ((rover->fofflags & FOF_BLOCKOTHERS) && !mobj->player)))
 		return false;
 
 	topheight    = P_GetFFloorTopZAt   (rover, mobj->x, mobj->y);
@@ -1450,10 +1450,10 @@ fixed_t P_GetMobjGravity(mobj_t *mo)
 
 		for (rover = mo->subsector->sector->ffloors; rover; rover = rover->next)
 		{
-			if (!(rover->flags & FF_EXISTS) || !P_InsideANonSolidFFloor(mo, rover)) // P_InsideANonSolidFFloor checks for FF_EXISTS itself, but let's not always call this function
+			if (!(rover->fofflags & FOF_EXISTS) || !P_InsideANonSolidFFloor(mo, rover)) // P_InsideANonSolidFFloor checks for FOF_EXISTS itself, but let's not always call this function
 				continue;
 
-			if ((rover->flags & (FF_SWIMMABLE|FF_GOOWATER)) == (FF_SWIMMABLE|FF_GOOWATER))
+			if ((rover->fofflags & (FOF_SWIMMABLE|FOF_GOOWATER)) == (FOF_SWIMMABLE|FOF_GOOWATER))
 				goopgravity = true;
 
 			gravfactor = P_GetSectorGravityFactor(rover->master->frontsector);
@@ -1714,10 +1714,10 @@ static void P_PushableCheckBustables(mobj_t *mo)
 
 		for (rover = node->m_sector->ffloors; rover; rover = rover->next)
 		{
-			if (!(rover->flags & FF_EXISTS))
+			if (!(rover->fofflags & FOF_EXISTS))
 				continue;
 
-			if (!(rover->flags & FF_BUSTUP))
+			if (!(rover->fofflags & FOF_BUSTUP))
 				continue;
 
 			if (!(rover->bustflags & FB_PUSHABLES))
@@ -2168,7 +2168,7 @@ void P_AdjustMobjFloorZ_FFloors(mobj_t *mo, sector_t *sector, UINT8 motype)
 
 	for (rover = sector->ffloors; rover; rover = rover->next)
 	{
-		if (!(rover->flags & FF_EXISTS))
+		if (!(rover->fofflags & FOF_EXISTS))
 			continue;
 
 		topheight = P_GetFOFTopZ(mo, sector, rover, mo->x, mo->y, NULL);
@@ -2176,16 +2176,16 @@ void P_AdjustMobjFloorZ_FFloors(mobj_t *mo, sector_t *sector, UINT8 motype)
 
 		if (mo->player && (P_CheckSolidLava(rover) || P_CanRunOnWater(mo->player, rover))) // only the player should stand on lava or run on water
 			;
-		else if (motype != 0 && rover->flags & FF_SWIMMABLE) // "scenery" only
+		else if (motype != 0 && rover->fofflags & FOF_SWIMMABLE) // "scenery" only
 			continue;
-		else if (rover->flags & FF_QUICKSAND) // quicksand
+		else if (rover->fofflags & FOF_QUICKSAND) // quicksand
 			;
 		else if (!( // if it's not either of the following...
-				(rover->flags & (FF_BLOCKPLAYER|FF_MARIO) && mo->player) // ...solid to players? (mario blocks are always solid from beneath to players)
-			    || (rover->flags & FF_BLOCKOTHERS && !mo->player) // ...solid to others?
+				(rover->fofflags & (FOF_BLOCKPLAYER|FOF_MARIO) && mo->player) // ...solid to players? (mario blocks are always solid from beneath to players)
+			    || (rover->fofflags & FOF_BLOCKOTHERS && !mo->player) // ...solid to others?
 				)) // ...don't take it into account.
 			continue;
-		if (rover->flags & FF_QUICKSAND)
+		if (rover->fofflags & FOF_QUICKSAND)
 		{
 			switch (motype)
 			{
@@ -2210,15 +2210,15 @@ void P_AdjustMobjFloorZ_FFloors(mobj_t *mo, sector_t *sector, UINT8 motype)
 		delta2 = thingtop - (bottomheight + ((topheight - bottomheight)/2));
 
 		if (topheight > mo->floorz && abs(delta1) < abs(delta2)
-			&& (rover->flags & FF_SOLID) // Non-FF_SOLID Mario blocks are only solid from bottom
-			&& !(rover->flags & FF_REVERSEPLATFORM)
-			&& ((P_MobjFlip(mo)*mo->momz >= 0) || (!(rover->flags & FF_PLATFORM)))) // In reverse gravity, only clip for FOFs that are intangible from their bottom (the "top" you're falling through) if you're coming from above ("below" in your frame of reference)
+			&& (rover->fofflags & FOF_SOLID) // Non-FOF_SOLID Mario blocks are only solid from bottom
+			&& !(rover->fofflags & FOF_REVERSEPLATFORM)
+			&& ((P_MobjFlip(mo)*mo->momz >= 0) || (!(rover->fofflags & FOF_PLATFORM)))) // In reverse gravity, only clip for FOFs that are intangible from their bottom (the "top" you're falling through) if you're coming from above ("below" in your frame of reference)
 		{
 			mo->floorz = topheight;
 		}
 		if (bottomheight < mo->ceilingz && abs(delta1) >= abs(delta2)
-			&& !(rover->flags & FF_PLATFORM)
-			&& ((P_MobjFlip(mo)*mo->momz >= 0) || ((rover->flags & FF_SOLID) && !(rover->flags & FF_REVERSEPLATFORM)))) // In normal gravity, only clip for FOFs that are intangible from the top if you're coming from below
+			&& !(rover->fofflags & FOF_PLATFORM)
+			&& ((P_MobjFlip(mo)*mo->momz >= 0) || ((rover->fofflags & FOF_SOLID) && !(rover->fofflags & FOF_REVERSEPLATFORM)))) // In normal gravity, only clip for FOFs that are intangible from the top if you're coming from below
 		{
 			mo->ceilingz = bottomheight;
 		}
@@ -2334,7 +2334,7 @@ boolean P_CheckDeathPitCollide(mobj_t *mo)
 
 boolean P_CheckSolidLava(ffloor_t *rover)
 {
-	return (rover->flags & FF_SWIMMABLE) && (rover->master->frontsector->damagetype == SD_LAVA);
+	return (rover->fofflags & FOF_SWIMMABLE) && (rover->master->frontsector->damagetype == SD_LAVA);
 }
 
 //
@@ -2828,10 +2828,10 @@ static void P_CheckMarioBlocks(mobj_t *mo)
 
 		for (rover = node->m_sector->ffloors; rover; rover = rover->next)
 		{
-			if (!(rover->flags & FF_EXISTS))
+			if (!(rover->fofflags & FOF_EXISTS))
 				continue;
 
-			if (!(rover->flags & FF_MARIO))
+			if (!(rover->fofflags & FOF_MARIO))
 				continue;
 
 			if (mo->eflags & MFE_VERTICALFLIP)
@@ -2840,7 +2840,7 @@ static void P_CheckMarioBlocks(mobj_t *mo)
 			if (*rover->bottomheight != mo->ceilingz)
 				continue;
 
-			if (rover->flags & FF_GOOWATER) // Brick block!
+			if (rover->fofflags & FOF_GOOWATER) // Brick block!
 				EV_CrumbleChain(node->m_sector, rover);
 			else // Question block!
 				EV_MarioBlock(rover, node->m_sector, mo);
@@ -3230,7 +3230,7 @@ boolean P_CanRunOnWater(player_t *player, ffloor_t *rover)
 
 	if (!player->powers[pw_carry] && !player->homing
 		&& ((player->powers[pw_super] || player->charflags & SF_RUNONWATER || player->dashmode >= DASHMODE_THRESHOLD) && doifit)
-		&& (rover->flags & FF_SWIMMABLE) && !(player->pflags & PF_SPINNING) && player->speed > FixedMul(player->runspeed, player->mo->scale)
+		&& (rover->fofflags & FOF_SWIMMABLE) && !(player->pflags & PF_SPINNING) && player->speed > FixedMul(player->runspeed, player->mo->scale)
 		&& !(player->pflags & PF_SLIDING)
 		&& abs(playerbottom - surfaceheight) < FixedMul(30*FRACUNIT, player->mo->scale))
 		return true;
@@ -3264,9 +3264,9 @@ void P_MobjCheckWater(mobj_t *mobj)
 	for (rover = sector->ffloors; rover; rover = rover->next)
 	{
 		fixed_t topheight, bottomheight;
-		if (!(rover->flags & FF_EXISTS) || !(rover->flags & FF_SWIMMABLE)
-		 || (((rover->flags & FF_BLOCKPLAYER) && mobj->player)
-		 || ((rover->flags & FF_BLOCKOTHERS) && !mobj->player)))
+		if (!(rover->fofflags & FOF_EXISTS) || !(rover->fofflags & FOF_SWIMMABLE)
+		 || (((rover->fofflags & FOF_BLOCKPLAYER) && mobj->player)
+		 || ((rover->fofflags & FOF_BLOCKOTHERS) && !mobj->player)))
 			continue;
 
 		topheight = P_GetSpecialTopZ(mobj, sectors + rover->secnum, sector);
@@ -3304,7 +3304,7 @@ void P_MobjCheckWater(mobj_t *mobj)
 			if (rover->master->frontsector->damagetype == SD_FIRE || rover->master->frontsector->damagetype == SD_LAVA)
 				mobj->eflags |= MFE_TOUCHLAVA;
 
-			if (rover->flags & FF_GOOWATER && !(mobj->flags & MF_NOGRAVITY))
+			if (rover->fofflags & FOF_GOOWATER && !(mobj->flags & MF_NOGRAVITY))
 				mobj->eflags |= MFE_GOOWATER;
 		}
 	}
@@ -3512,7 +3512,7 @@ static void P_SceneryCheckWater(mobj_t *mobj)
 
 		for (rover = sector->ffloors; rover; rover = rover->next)
 		{
-			if (!(rover->flags & FF_EXISTS) || !(rover->flags & FF_SWIMMABLE) || rover->flags & FF_BLOCKOTHERS)
+			if (!(rover->fofflags & FOF_EXISTS) || !(rover->fofflags & FOF_SWIMMABLE) || rover->fofflags & FOF_BLOCKOTHERS)
 				continue;
 
 			topheight    = P_GetFFloorTopZAt   (rover, mobj->x, mobj->y);
@@ -3558,7 +3558,7 @@ static boolean P_CameraCheckHeat(camera_t *thiscam)
 
 		for (rover = sector->ffloors; rover; rover = rover->next)
 		{
-			if (!(rover->flags & FF_EXISTS))
+			if (!(rover->fofflags & FOF_EXISTS))
 				continue;
 
 			if (halfheight >= P_GetFFloorTopZAt(rover, thiscam->x, thiscam->y))
@@ -3588,7 +3588,7 @@ static boolean P_CameraCheckWater(camera_t *thiscam)
 
 		for (rover = sector->ffloors; rover; rover = rover->next)
 		{
-			if (!(rover->flags & FF_EXISTS) || !(rover->flags & FF_SWIMMABLE) || rover->flags & FF_BLOCKOTHERS)
+			if (!(rover->fofflags & FOF_EXISTS) || !(rover->fofflags & FOF_SWIMMABLE) || rover->fofflags & FOF_BLOCKOTHERS)
 				continue;
 
 			if (halfheight >= P_GetFFloorTopZAt(rover, thiscam->x, thiscam->y))
@@ -3782,10 +3782,10 @@ static void P_CheckCrumblingPlatforms(mobj_t *mobj)
 
 		for (rover = node->m_sector->ffloors; rover; rover = rover->next)
 		{
-			if (!(rover->flags & FF_EXISTS))
+			if (!(rover->fofflags & FOF_EXISTS))
 				continue;
 
-			if (!(rover->flags & FF_CRUMBLE))
+			if (!(rover->fofflags & FOF_CRUMBLE))
 				continue;
 
 			if (mobj->eflags & MFE_VERTICALFLIP)
@@ -3799,7 +3799,7 @@ static void P_CheckCrumblingPlatforms(mobj_t *mobj)
 					continue;
 			}
 
-			EV_StartCrumble(rover->master->frontsector, rover, (rover->flags & FF_FLOATBOB), mobj->player, rover->alpha, !(rover->flags & FF_NORETURN));
+			EV_StartCrumble(rover->master->frontsector, rover, (rover->fofflags & FOF_FLOATBOB), mobj->player, rover->alpha, !(rover->fofflags & FOF_NORETURN));
 		}
 	}
 }
@@ -3817,10 +3817,10 @@ static boolean P_MobjTouchesSectorWithWater(mobj_t *mobj)
 
 		for (rover = node->m_sector->ffloors; rover; rover = rover->next)
 		{
-			if (!(rover->flags & FF_EXISTS))
+			if (!(rover->fofflags & FOF_EXISTS))
 				continue;
 
-			if (!(rover->flags & FF_SWIMMABLE))
+			if (!(rover->fofflags & FOF_SWIMMABLE))
 				continue;
 
 			return true;
@@ -3851,10 +3851,10 @@ static void P_CheckFloatbobPlatforms(mobj_t *mobj)
 
 		for (rover = node->m_sector->ffloors; rover; rover = rover->next)
 		{
-			if (!(rover->flags & FF_EXISTS))
+			if (!(rover->fofflags & FOF_EXISTS))
 				continue;
 
-			if (!(rover->flags & FF_FLOATBOB))
+			if (!(rover->fofflags & FOF_FLOATBOB))
 				continue;
 
 
@@ -3984,10 +3984,10 @@ static void CalculatePrecipFloor(precipmobj_t *mobj)
 		for (rover = mobjsecsubsec->ffloors; rover; rover = rover->next)
 		{
 			// If it exists, it'll get rained on.
-			if (!(rover->flags & FF_EXISTS))
+			if (!(rover->fofflags & FOF_EXISTS))
 				continue;
 
-			if (!(rover->flags & FF_BLOCKOTHERS) && !(rover->flags & FF_SWIMMABLE))
+			if (!(rover->fofflags & FOF_BLOCKOTHERS) && !(rover->fofflags & FOF_SWIMMABLE))
 				continue;
 
 			topheight = P_GetFFloorTopZAt(rover, mobj->x, mobj->y);
@@ -4090,9 +4090,9 @@ static void P_KillRingsInLava(mobj_t *mo)
 
 			for (rover = node->m_sector->ffloors; rover; rover = rover->next) // go through all fofs in the sector
 			{
-				if (!(rover->flags & FF_EXISTS)) continue; // fof must be real
+				if (!(rover->fofflags & FOF_EXISTS)) continue; // fof must be real
 
-				if (!(rover->flags & FF_SWIMMABLE))
+				if (!(rover->fofflags & FOF_SWIMMABLE))
 					continue; // fof must be water
 
 				if (rover->master->frontsector->damagetype != SD_FIRE && rover->master->frontsector->damagetype != SD_LAVA)
@@ -4733,14 +4733,14 @@ static void P_Boss4DestroyCage(mobj_t *mobj)
 		{
 			rsec = &sectors[sector->attached[a]];
 			for (rover = rsec->ffloors; rover; rover = rover->next)
-				if (rover->flags & FF_EXISTS && rover->secnum == (size_t)snum)
+				if (rover->fofflags & FOF_EXISTS && rover->secnum == (size_t)snum)
 				{
-					if (rover->flags & FF_RENDERALL) // checking for FF_RENDERANY.
+					if (rover->fofflags & FOF_RENDERALL) // checking for FF_RENDERANY.
 						EV_CrumbleChain(rsec, rover); // This FOF is visible to some extent? Crumble it.
 					else // Completely invisible FOF
 					{
 						// no longer exists (can't collide with again)
-						rover->flags &= ~FF_EXISTS;
+						rover->fofflags &= ~FOF_EXISTS;
 						sector->moved = true;
 						rsec->moved = true;
 					}
diff --git a/src/p_saveg.c b/src/p_saveg.c
index 668ca08f002ea983ea4538ab9a95a1d2a1a1fc36..07b3d8640ecdbc588f28d087463a2b5bc7ff2c27 100644
--- a/src/p_saveg.c
+++ b/src/p_saveg.c
@@ -915,7 +915,7 @@ static boolean CheckFFloorDiff(const sector_t *ss)
 
 	for (rover = ss->ffloors; rover; rover = rover->next)
 	{
-		if (rover->flags != rover->spawnflags
+		if (rover->fofflags != rover->spawnflags
 		|| rover->alpha != rover->spawnalpha)
 			{
 				return true; // we found an FOF that changed!
@@ -935,7 +935,7 @@ static void ArchiveFFloors(const sector_t *ss)
 	for (rover = ss->ffloors; rover; rover = rover->next)
 	{
 		fflr_diff = 0; // reset diff flags
-		if (rover->flags != rover->spawnflags)
+		if (rover->fofflags != rover->spawnflags)
 			fflr_diff |= FD_FLAGS;
 		if (rover->alpha != rover->spawnalpha)
 			fflr_diff |= FD_ALPHA;
@@ -945,7 +945,7 @@ static void ArchiveFFloors(const sector_t *ss)
 			WRITEUINT16(save_p, j); // save ffloor "number"
 			WRITEUINT8(save_p, fflr_diff);
 			if (fflr_diff & FD_FLAGS)
-				WRITEUINT32(save_p, rover->flags);
+				WRITEUINT32(save_p, rover->fofflags);
 			if (fflr_diff & FD_ALPHA)
 				WRITEINT16(save_p, rover->alpha);
 		}
@@ -983,7 +983,7 @@ static void UnArchiveFFloors(const sector_t *ss)
 		fflr_diff = READUINT8(save_p);
 
 		if (fflr_diff & FD_FLAGS)
-			rover->flags = READUINT32(save_p);
+			rover->fofflags = READUINT32(save_p);
 		if (fflr_diff & FD_ALPHA)
 			rover->alpha = READINT16(save_p);
 
diff --git a/src/p_setup.c b/src/p_setup.c
index 146d5d30235416dfd9a4d42ada19f3acf3b8467e..5c2a36474ed05a4a0d5c2d905fb74bcf18aeebd6 100644
--- a/src/p_setup.c
+++ b/src/p_setup.c
@@ -2150,9 +2150,9 @@ static void P_WriteTextmap(void)
 				freetag = Tag_NextUnused(freetag);
 				break;
 			case 259:
-				if (wlines[i].args[3] & FF_QUICKSAND)
+				if (wlines[i].args[3] & FOF_QUICKSAND)
 					CONS_Alert(CONS_WARNING, M_GetText("Quicksand properties of custom FOF on linedef %s cannot be converted. Use linedef type 75 instead.\n"), sizeu1(i));
-				if (wlines[i].args[3] & FF_BUSTUP)
+				if (wlines[i].args[3] & FOF_BUSTUP)
 					CONS_Alert(CONS_WARNING, M_GetText("Bustable properties of custom FOF on linedef %s cannot be converted. Use linedef type 74 instead.\n"), sizeu1(i));
 				break;
 			case 412:
@@ -3989,6 +3989,81 @@ static void P_SetBinaryFOFAlpha(line_t *line)
 	}
 }
 
+static INT32 P_GetFOFFlags(INT32 oldflags)
+{
+	INT32 result = 0;
+	if (oldflags & FF_OLD_EXISTS)
+		result |= FOF_EXISTS;
+	if (oldflags & FF_OLD_BLOCKPLAYER)
+		result |= FOF_BLOCKPLAYER;
+	if (oldflags & FF_OLD_BLOCKOTHERS)
+		result |= FOF_BLOCKOTHERS;
+	if (oldflags & FF_OLD_RENDERSIDES)
+		result |= FOF_RENDERSIDES;
+	if (oldflags & FF_OLD_RENDERPLANES)
+		result |= FOF_RENDERPLANES;
+	if (oldflags & FF_OLD_SWIMMABLE)
+		result |= FOF_SWIMMABLE;
+	if (oldflags & FF_OLD_NOSHADE)
+		result |= FOF_NOSHADE;
+	if (oldflags & FF_OLD_CUTSOLIDS)
+		result |= FOF_CUTSOLIDS;
+	if (oldflags & FF_OLD_CUTEXTRA)
+		result |= FOF_CUTEXTRA;
+	if (oldflags & FF_OLD_CUTSPRITES)
+		result |= FOF_CUTSPRITES;
+	if (oldflags & FF_OLD_BOTHPLANES)
+		result |= FOF_BOTHPLANES;
+	if (oldflags & FF_OLD_EXTRA)
+		result |= FOF_EXTRA;
+	if (oldflags & FF_OLD_TRANSLUCENT)
+		result |= FOF_TRANSLUCENT;
+	if (oldflags & FF_OLD_FOG)
+		result |= FOF_FOG;
+	if (oldflags & FF_OLD_INVERTPLANES)
+		result |= FOF_INVERTPLANES;
+	if (oldflags & FF_OLD_ALLSIDES)
+		result |= FOF_ALLSIDES;
+	if (oldflags & FF_OLD_INVERTSIDES)
+		result |= FOF_INVERTSIDES;
+	if (oldflags & FF_OLD_DOUBLESHADOW)
+		result |= FOF_DOUBLESHADOW;
+	if (oldflags & FF_OLD_FLOATBOB)
+		result |= FOF_FLOATBOB;
+	if (oldflags & FF_OLD_NORETURN)
+		result |= FOF_NORETURN;
+	if (oldflags & FF_OLD_CRUMBLE)
+		result |= FOF_CRUMBLE;
+	if (oldflags & FF_OLD_GOOWATER)
+		result |= FOF_GOOWATER;
+	if (oldflags & FF_OLD_MARIO)
+		result |= FOF_MARIO;
+	if (oldflags & FF_OLD_BUSTUP)
+		result |= FOF_BUSTUP;
+	if (oldflags & FF_OLD_QUICKSAND)
+		result |= FOF_QUICKSAND;
+	if (oldflags & FF_OLD_PLATFORM)
+		result |= FOF_PLATFORM;
+	if (oldflags & FF_OLD_REVERSEPLATFORM)
+		result |= FOF_REVERSEPLATFORM;
+	if (oldflags & FF_OLD_RIPPLE)
+		result |= FOF_RIPPLE;
+	if (oldflags & FF_OLD_COLORMAPONLY)
+		result |= FOF_COLORMAPONLY;
+	return result;
+}
+
+static INT32 P_GetFOFBusttype(INT32 oldflags)
+{
+	if (oldflags & FF_OLD_SHATTER)
+		return TMFB_TOUCH;
+	if (oldflags & FF_OLD_SPINBUST)
+		return TMFB_SPIN;
+	if (oldflags & FF_OLD_STRONGBUST)
+		return TMFB_STRONG;
+	return TMFB_REGULAR;
+}
+
 static void P_ConvertBinaryLinedefTypes(void)
 {
 	size_t i;
@@ -4637,17 +4712,19 @@ static void P_ConvertBinaryLinedefTypes(void)
 				I_Error("Custom FOF (tag %d) found without a linedef back side!", tag);
 
 			lines[i].args[0] = tag;
-			lines[i].args[3] = sides[lines[i].sidenum[1]].toptexture;
+			lines[i].args[3] = P_GetFOFFlags(sides[lines[i].sidenum[1]].toptexture);
 			if (lines[i].flags & ML_EFFECT6)
-				lines[i].args[3] |= FF_SPLAT;
-			lines[i].args[4] = sides[lines[i].sidenum[1]].midtexture;
-			if (lines[i].args[3] & FF_TRANSLUCENT)
+				lines[i].args[3] |= FOF_SPLAT;
+			lines[i].args[4] = P_GetFOFBusttype(sides[lines[i].sidenum[1]].toptexture);
+			if (sides[lines[i].sidenum[1]].toptexture & FF_OLD_SHATTERBOTTOM)
+				lines[i].args[4] |= TMFB_ONLYBOTTOM;
+			if (lines[i].args[3] & FOF_TRANSLUCENT)
 			{
 				P_SetBinaryFOFAlpha(&lines[i]);
 
 				//Replicate old hack: Translucent FOFs set to full opacity cut cyan pixels
 				if (lines[i].args[1] == 256)
-					lines[i].args[3] |= FF_SPLAT;
+					lines[i].args[3] |= FOF_SPLAT;
 			}
 			else
 				lines[i].args[1] = 255;
@@ -5846,7 +5923,7 @@ static void P_ConvertBinarySectorTypes(void)
 					if (line->flags & ML_BLOCKMONSTERS)
 						continue;
 
-					if (line->special == 120 || (line->special == 259 && (line->args[2] & FF_SWIMMABLE)))
+					if (line->special == 120 || (line->special == 259 && (line->args[2] & FOF_SWIMMABLE)))
 					{
 						isLava = true;
 						break;
diff --git a/src/p_sight.c b/src/p_sight.c
index 1aa231a6c3db613e2bc573b312f0ba4c8d367853..4023744dc39b50441e16cd5aa5802a794fb88c6d 100644
--- a/src/p_sight.c
+++ b/src/p_sight.c
@@ -306,8 +306,8 @@ static boolean P_CrossSubsector(size_t num, register los_t *los)
 			// check front sector's FOFs first
 			for (rover = front->ffloors; rover; rover = rover->next)
 			{
-				if (!(rover->flags & FF_EXISTS)
-					|| !(rover->flags & FF_RENDERSIDES) || (rover->flags & (FF_TRANSLUCENT|FF_FOG)))
+				if (!(rover->fofflags & FOF_EXISTS)
+					|| !(rover->fofflags & FOF_RENDERSIDES) || (rover->fofflags & (FOF_TRANSLUCENT|FOF_FOG)))
 				{
 					continue;
 				}
@@ -322,8 +322,8 @@ static boolean P_CrossSubsector(size_t num, register los_t *los)
 			// check back sector's FOFs as well
 			for (rover = back->ffloors; rover; rover = rover->next)
 			{
-				if (!(rover->flags & FF_EXISTS)
-					|| !(rover->flags & FF_RENDERSIDES) || (rover->flags & (FF_TRANSLUCENT|FF_FOG)))
+				if (!(rover->fofflags & FOF_EXISTS)
+					|| !(rover->fofflags & FOF_RENDERSIDES) || (rover->fofflags & (FOF_TRANSLUCENT|FOF_FOG)))
 				{
 					continue;
 				}
@@ -451,8 +451,8 @@ boolean P_CheckSight(mobj_t *t1, mobj_t *t2)
 			// Allow sight through water, fog, etc.
 			/// \todo Improve by checking fog density/translucency
 			/// and setting a sight limit.
-			if (!(rover->flags & FF_EXISTS)
-				|| !(rover->flags & FF_RENDERPLANES) || (rover->flags & (FF_TRANSLUCENT|FF_FOG)))
+			if (!(rover->fofflags & FOF_EXISTS)
+				|| !(rover->fofflags & FOF_RENDERPLANES) || (rover->fofflags & (FOF_TRANSLUCENT|FOF_FOG)))
 			{
 				continue;
 			}
@@ -470,10 +470,10 @@ boolean P_CheckSight(mobj_t *t1, mobj_t *t2)
 				return false;
 			}
 
-			if (rover->flags & FF_SOLID)
+			if (rover->fofflags & FOF_SOLID)
 				continue; // shortcut since neither mobj can be inside the 3dfloor
 
-			if (rover->flags & FF_BOTHPLANES || !(rover->flags & FF_INVERTPLANES))
+			if (rover->fofflags & FOF_BOTHPLANES || !(rover->fofflags & FOF_INVERTPLANES))
 			{
 				if (los.sightzstart >= topz1 && t2->z + t2->height < topz2)
 					return false; // blocked by upper outside plane
@@ -482,7 +482,7 @@ boolean P_CheckSight(mobj_t *t1, mobj_t *t2)
 					return false; // blocked by lower outside plane
 			}
 
-			if (rover->flags & FF_BOTHPLANES || rover->flags & FF_INVERTPLANES)
+			if (rover->fofflags & FOF_BOTHPLANES || rover->fofflags & FOF_INVERTPLANES)
 			{
 				if (los.sightzstart < topz1 && t2->z >= topz2)
 					return false; // blocked by upper inside plane
diff --git a/src/p_spec.c b/src/p_spec.c
index 78878de1da721e5a4c908f409cbdaab791315e7b..d29167a88531dee3751929d16fafa6c3f802659b 100644
--- a/src/p_spec.c
+++ b/src/p_spec.c
@@ -3033,16 +3033,16 @@ static void P_ProcessLineSpecial(line_t *line, mobj_t *mo, sector_t *callsec)
 						{
 							foundrover = true;
 
-							oldflags = rover->flags;
+							oldflags = rover->fofflags;
 
 							// Abracadabra!
 							if (line->args[2])
-								rover->flags |= FF_EXISTS;
+								rover->fofflags |= FOF_EXISTS;
 							else
-								rover->flags &= ~FF_EXISTS;
+								rover->fofflags &= ~FOF_EXISTS;
 
 							// if flags changed, reset sector's light list
-							if (rover->flags != oldflags)
+							if (rover->fofflags != oldflags)
 							{
 								sec->moved = true;
 								P_RecalcPrecipInSector(sec);
@@ -3059,7 +3059,7 @@ static void P_ProcessLineSpecial(line_t *line, mobj_t *mo, sector_t *callsec)
 			}
 			break;
 
-		case 446: // Make block fall remotely (acts like FF_CRUMBLE)
+		case 446: // Make block fall remotely (acts like FOF_CRUMBLE)
 			{
 				INT16 sectag = (INT16)(line->args[0]);
 				INT16 foftag = (INT16)(line->args[1]);
@@ -3092,9 +3092,9 @@ static void P_ProcessLineSpecial(line_t *line, mobj_t *mo, sector_t *callsec)
 							foundrover = true;
 
 							if (line->args[2] & TMFR_CHECKFLAG) // FOF flags determine respawn ability instead?
-								respawn = !(rover->flags & FF_NORETURN) ^ !!(line->args[2] & TMFR_NORETURN); // TMFR_NORETURN inverts
+								respawn = !(rover->fofflags & FOF_NORETURN) ^ !!(line->args[2] & TMFR_NORETURN); // TMFR_NORETURN inverts
 
-							EV_StartCrumble(rover->master->frontsector, rover, (rover->flags & FF_FLOATBOB), player, rover->alpha, respawn);
+							EV_StartCrumble(rover->master->frontsector, rover, (rover->fofflags & FOF_FLOATBOB), player, rover->alpha, respawn);
 						}
 					}
 
@@ -3276,10 +3276,10 @@ static void P_ProcessLineSpecial(line_t *line, mobj_t *mo, sector_t *callsec)
 						// initialize its alpha to 1
 						// for relative alpha calc
 						if (!(line->args[3] & TMST_DONTDOTRANSLUCENT) &&      // do translucent
-							(rover->spawnflags & FF_NOSHADE) && // do not include light blocks, which don't set FF_NOSHADE
-							!(rover->spawnflags & FF_RENDERSIDES) &&
-							!(rover->spawnflags & FF_RENDERPLANES) &&
-							!(rover->flags & FF_RENDERALL))
+							(rover->spawnflags & FOF_NOSHADE) && // do not include light blocks, which don't set FOF_NOSHADE
+							!(rover->spawnflags & FOF_RENDERSIDES) &&
+							!(rover->spawnflags & FOF_RENDERPLANES) &&
+							!(rover->fofflags & FOF_RENDERALL))
 							rover->alpha = 1;
 
 						P_RemoveFakeFloorFader(rover);
@@ -3288,8 +3288,8 @@ static void P_ProcessLineSpecial(line_t *line, mobj_t *mo, sector_t *callsec)
 							max(1, min(256, (line->args[3] & TMST_RELATIVE) ? rover->alpha + destvalue : destvalue)),
 							0,                                         // set alpha immediately
 							false, NULL,                               // tic-based logic
-							false,                                     // do not handle FF_EXISTS
-							!(line->args[3] & TMST_DONTDOTRANSLUCENT), // handle FF_TRANSLUCENT
+							false,                                     // do not handle FOF_EXISTS
+							!(line->args[3] & TMST_DONTDOTRANSLUCENT), // handle FOF_TRANSLUCENT
 							false,                                     // do not handle lighting
 							false,                                     // do not handle colormap
 							false,                                     // do not handle collision
@@ -3349,8 +3349,8 @@ static void P_ProcessLineSpecial(line_t *line, mobj_t *mo, sector_t *callsec)
 								speed,
 								(line->args[4] & TMFT_TICBASED),           // tic-based logic
 								(line->args[4] & TMFT_RELATIVE),           // Relative destvalue
-								!(line->args[4] & TMFT_DONTDOEXISTS),      // do not handle FF_EXISTS
-								!(line->args[4] & TMFT_DONTDOTRANSLUCENT), // do not handle FF_TRANSLUCENT
+								!(line->args[4] & TMFT_DONTDOEXISTS),      // do not handle FOF_EXISTS
+								!(line->args[4] & TMFT_DONTDOTRANSLUCENT), // do not handle FOF_TRANSLUCENT
 								!(line->args[4] & TMFT_DONTDOLIGHTING),    // do not handle lighting
 								!(line->args[4] & TMFT_DONTDOCOLORMAP),    // do not handle colormap
 								!(line->args[4] & TMFT_IGNORECOLLISION),   // do not handle collision
@@ -3362,10 +3362,10 @@ static void P_ProcessLineSpecial(line_t *line, mobj_t *mo, sector_t *callsec)
 							// initialize its alpha to 1
 							// for relative alpha calc
 							if (!(line->args[4] & TMFT_DONTDOTRANSLUCENT) &&      // do translucent
-								(rover->spawnflags & FF_NOSHADE) && // do not include light blocks, which don't set FF_NOSHADE
-								!(rover->spawnflags & FF_RENDERSIDES) &&
-								!(rover->spawnflags & FF_RENDERPLANES) &&
-								!(rover->flags & FF_RENDERALL))
+								(rover->spawnflags & FOF_NOSHADE) && // do not include light blocks, which don't set FOF_NOSHADE
+								!(rover->spawnflags & FOF_RENDERSIDES) &&
+								!(rover->spawnflags & FOF_RENDERPLANES) &&
+								!(rover->fofflags & FOF_RENDERALL))
 								rover->alpha = 1;
 
 							P_RemoveFakeFloorFader(rover);
@@ -3374,8 +3374,8 @@ static void P_ProcessLineSpecial(line_t *line, mobj_t *mo, sector_t *callsec)
 								max(1, min(256, (line->args[4] & TMFT_RELATIVE) ? rover->alpha + destvalue : destvalue)),
 								0,                                         // set alpha immediately
 								false, NULL,                               // tic-based logic
-								!(line->args[4] & TMFT_DONTDOEXISTS),      // do not handle FF_EXISTS
-								!(line->args[4] & TMFT_DONTDOTRANSLUCENT), // do not handle FF_TRANSLUCENT
+								!(line->args[4] & TMFT_DONTDOEXISTS),      // do not handle FOF_EXISTS
+								!(line->args[4] & TMFT_DONTDOTRANSLUCENT), // do not handle FOF_TRANSLUCENT
 								!(line->args[4] & TMFT_DONTDOLIGHTING),    // do not handle lighting
 								!(line->args[4] & TMFT_DONTDOCOLORMAP),    // do not handle colormap
 								!(line->args[4] & TMFT_IGNORECOLLISION),   // do not handle collision
@@ -3953,7 +3953,7 @@ boolean P_IsFlagAtBase(mobjtype_t flag)
 
 			for (rover = mo->subsector->sector->ffloors; rover; rover = rover->next)
 			{
-				if (!(rover->flags & FF_EXISTS))
+				if (!(rover->fofflags & FOF_EXISTS))
 					continue;
 
 				if (!(rover->master->frontsector->specialflags & specialflag))
@@ -3987,8 +3987,8 @@ boolean P_IsMobjTouching3DFloor(mobj_t *mo, ffloor_t *ffloor, sector_t *sec)
 	fixed_t topheight = P_GetSpecialTopZ(mo, sectors + ffloor->secnum, sec);
 	fixed_t bottomheight = P_GetSpecialBottomZ(mo, sectors + ffloor->secnum, sec);
 
-	if (((ffloor->flags & FF_BLOCKPLAYER) && mo->player)
-		|| ((ffloor->flags & FF_BLOCKOTHERS) && !mo->player))
+	if (((ffloor->fofflags & FOF_BLOCKPLAYER) && mo->player)
+		|| ((ffloor->fofflags & FOF_BLOCKOTHERS) && !mo->player))
 	{
 		// Solid 3D floor: Mobj must touch the top or bottom
 		return P_IsMobjTouchingPlane(mo, ffloor->master->frontsector, topheight, bottomheight);
@@ -4026,7 +4026,7 @@ static sector_t *P_MobjTouching3DFloorSpecial(mobj_t *mo, sector_t *sector, INT3
 		if (GETSECSPECIAL(rover->master->frontsector->special, section) != number)
 			continue;
 
-		if (!(rover->flags & FF_EXISTS))
+		if (!(rover->fofflags & FOF_EXISTS))
 			continue;
 
 		if (!P_IsMobjTouching3DFloor(mo, rover, sector))
@@ -4050,7 +4050,7 @@ static sector_t *P_MobjTouching3DFloorSpecialFlag(mobj_t *mo, sector_t *sector,
 		if (!(rover->master->frontsector->specialflags & flag))
 			continue;
 
-		if (!(rover->flags & FF_EXISTS))
+		if (!(rover->fofflags & FOF_EXISTS))
 			continue;
 
 		if (!P_IsMobjTouching3DFloor(mo, rover, sector))
@@ -4238,7 +4238,7 @@ static sector_t *P_CheckPlayer3DFloorTrigger(player_t *player, sector_t *sector,
 		if (rover->master->frontsector->triggerer == TO_MOBJ)
 			continue;
 
-		if (!(rover->flags & FF_EXISTS))
+		if (!(rover->fofflags & FOF_EXISTS))
 			continue;
 
 		if (!Tag_Find(&sourceline->tags, rover->master->frontsector->triggertag))
@@ -5152,7 +5152,7 @@ static void P_PlayerOnSpecial3DFloor(player_t *player, sector_t *sector)
 		if (!P_SectorHasSpecial(rover->master->frontsector))
 			continue;
 
-		if (!(rover->flags & FF_EXISTS))
+		if (!(rover->fofflags & FOF_EXISTS))
 			continue;
 
 		if (!P_IsMobjTouching3DFloor(player->mo, rover, sector))
@@ -5259,7 +5259,7 @@ static void P_CheckMobj3DFloorTrigger(mobj_t *mo, sector_t *sec)
 		if (rover->master->frontsector->triggerer != TO_MOBJ)
 			continue;
 
-		if (!(rover->flags & FF_EXISTS))
+		if (!(rover->fofflags & FOF_EXISTS))
 			continue;
 
 		if (!P_IsMobjTouching3DFloor(mo, rover, sec))
@@ -5525,7 +5525,7 @@ static ffloor_t *P_AddFakeFloor(sector_t *sec, sector_t *sec2, line_t *master, I
 		sec2->attachedsolid = Z_Malloc(sizeof (*sec2->attachedsolid) * sec2->maxattached, PU_STATIC, NULL);
 		sec2->attached[0] = sec - sectors;
 		sec2->numattached = 1;
-		sec2->attachedsolid[0] = (flags & FF_SOLID);
+		sec2->attachedsolid[0] = (flags & FOF_SOLID);
 	}
 	else
 	{
@@ -5540,7 +5540,7 @@ static ffloor_t *P_AddFakeFloor(sector_t *sec, sector_t *sec2, line_t *master, I
 			sec2->attachedsolid = Z_Realloc(sec2->attachedsolid, sizeof (*sec2->attachedsolid) * sec2->maxattached, PU_STATIC, NULL);
 		}
 		sec2->attached[sec2->numattached] = sec - sectors;
-		sec2->attachedsolid[sec2->numattached] = (flags & FF_SOLID);
+		sec2->attachedsolid[sec2->numattached] = (flags & FOF_SOLID);
 		sec2->numattached++;
 	}
 
@@ -5570,7 +5570,7 @@ static ffloor_t *P_AddFakeFloor(sector_t *sec, sector_t *sec2, line_t *master, I
 	if (sec2->hasslope)
 		sec->hasslope = true;
 
-	fflr->spawnflags = fflr->flags = flags;
+	fflr->spawnflags = fflr->fofflags = flags;
 	fflr->master = master;
 	fflr->norender = INFTICS;
 	fflr->fadingdata = NULL;
@@ -5618,10 +5618,10 @@ static ffloor_t *P_AddFakeFloor(sector_t *sec, sector_t *sec2, line_t *master, I
 	}
 
 	fflr->alpha = max(0, min(0xff, alpha));
-	if (fflr->alpha < 0xff || flags & FF_SPLAT)
+	if (fflr->alpha < 0xff || flags & FOF_SPLAT)
 	{
-		fflr->flags |= FF_TRANSLUCENT;
-		fflr->spawnflags = fflr->flags;
+		fflr->fofflags |= FOF_TRANSLUCENT;
+		fflr->spawnflags = fflr->fofflags;
 	}
 	fflr->spawnalpha = fflr->alpha; // save for netgames
 
@@ -5645,23 +5645,23 @@ static ffloor_t *P_AddFakeFloor(sector_t *sec, sector_t *sec2, line_t *master, I
 			break;
 	}
 
-	if (flags & FF_QUICKSAND)
+	if (flags & FOF_QUICKSAND)
 		CheckForQuicksand = true;
 
-	if (flags & FF_BUSTUP)
+	if (flags & FOF_BUSTUP)
 		CheckForBustableBlocks = true;
 
-	if ((flags & FF_MARIO))
+	if ((flags & FOF_MARIO))
 	{
-		if (!(flags & FF_GOOWATER)) // Don't change the textures of a brick block, just a question block
+		if (!(flags & FOF_GOOWATER)) // Don't change the textures of a brick block, just a question block
 			P_AddBlockThinker(sec2, master);
 		CheckForMarioBlocks = true;
 	}
 
-	if ((flags & FF_CRUMBLE))
+	if ((flags & FOF_CRUMBLE))
 		sec2->crumblestate = CRUMBLE_WAIT;
 
-	if ((flags & FF_FLOATBOB))
+	if ((flags & FOF_FLOATBOB))
 	{
 		P_AddFloatThinker(sec2, master->args[0], master);
 		CheckForFloatBob = true;
@@ -5944,14 +5944,14 @@ void T_LaserFlash(laserthink_t *flash)
 			if (fflr->master != flash->sourceline)
 				continue;
 
-			if (!(fflr->flags & FF_EXISTS))
+			if (!(fflr->fofflags & FOF_EXISTS))
 				break;
 
 			if (leveltime & 2)
-				//fflr->flags |= FF_RENDERALL;
+				//fflr->flags |= FOF_RENDERALL;
 				fflr->alpha = 0xB0;
 			else
-				//fflr->flags &= ~FF_RENDERALL;
+				//fflr->flags &= ~FOF_RENDERALL;
 				fflr->alpha = 0x90;
 
 			top    = P_GetFFloorTopZAt   (fflr, sector->soundorg.x, sector->soundorg.y);
@@ -6089,8 +6089,8 @@ static void P_MakeFOFBouncy(line_t *paramline, line_t *masterline)
 			if (rover->master != masterline)
 				continue;
 
-			rover->flags |= FF_BOUNCY;
-			rover->spawnflags |= FF_BOUNCY;
+			rover->fofflags |= FOF_BOUNCY;
+			rover->spawnflags |= FOF_BOUNCY;
 			rover->bouncestrength = (paramline->args[1]<< FRACBITS)/100;
 			CheckForBouncySector = true;
 			break;
@@ -6467,117 +6467,117 @@ void P_SpawnSpecials(boolean fromnetsave)
 				break;
 
 			case 100: // FOF (solid)
-				ffloorflags = FF_EXISTS|FF_SOLID|FF_RENDERALL;
+				ffloorflags = FOF_EXISTS|FOF_SOLID|FOF_RENDERALL;
 
 				//Appearance settings
 				if (lines[i].args[3] & TMFA_NOPLANES)
-					ffloorflags &= ~FF_RENDERPLANES;
+					ffloorflags &= ~FOF_RENDERPLANES;
 				if (lines[i].args[3] & TMFA_NOSIDES)
-					ffloorflags &= ~FF_RENDERSIDES;
+					ffloorflags &= ~FOF_RENDERSIDES;
 				if (lines[i].args[3] & TMFA_INSIDES)
 				{
-					if (ffloorflags & FF_RENDERPLANES)
-						ffloorflags |= FF_BOTHPLANES;
-					if (ffloorflags & FF_RENDERSIDES)
-						ffloorflags |= FF_ALLSIDES;
+					if (ffloorflags & FOF_RENDERPLANES)
+						ffloorflags |= FOF_BOTHPLANES;
+					if (ffloorflags & FOF_RENDERSIDES)
+						ffloorflags |= FOF_ALLSIDES;
 				}
 				if (lines[i].args[3] & TMFA_ONLYINSIDES)
 				{
-					if (ffloorflags & FF_RENDERPLANES)
-						ffloorflags |= FF_INVERTPLANES;
-					if (ffloorflags & FF_RENDERSIDES)
-						ffloorflags |= FF_INVERTSIDES;
+					if (ffloorflags & FOF_RENDERPLANES)
+						ffloorflags |= FOF_INVERTPLANES;
+					if (ffloorflags & FOF_RENDERSIDES)
+						ffloorflags |= FOF_INVERTSIDES;
 				}
 				if (lines[i].args[3] & TMFA_NOSHADE)
-					ffloorflags |= FF_NOSHADE;
+					ffloorflags |= FOF_NOSHADE;
 				if (lines[i].args[3] & TMFA_SPLAT)
-					ffloorflags |= FF_SPLAT;
+					ffloorflags |= FOF_SPLAT;
 
 				//Tangibility settings
 				if (lines[i].args[4] & TMFT_INTANGIBLETOP)
-					ffloorflags |= FF_REVERSEPLATFORM;
+					ffloorflags |= FOF_REVERSEPLATFORM;
 				if (lines[i].args[4] & TMFT_INTANGIBLEBOTTOM)
-					ffloorflags |= FF_PLATFORM;
+					ffloorflags |= FOF_PLATFORM;
 				if (lines[i].args[4] & TMFT_DONTBLOCKPLAYER)
-					ffloorflags &= ~FF_BLOCKPLAYER;
+					ffloorflags &= ~FOF_BLOCKPLAYER;
 				if (lines[i].args[4] & TMFT_DONTBLOCKOTHERS)
-					ffloorflags &= ~FF_BLOCKOTHERS;
+					ffloorflags &= ~FOF_BLOCKOTHERS;
 
 				//Cutting options
-				if (ffloorflags & FF_RENDERALL)
+				if (ffloorflags & FOF_RENDERALL)
 				{
 					//If translucent or player can enter it, cut inner walls
 					if ((lines[i].args[1] < 255) || (lines[i].args[4] & TMFT_VISIBLEFROMINSIDE))
-						ffloorflags |= FF_CUTEXTRA|FF_EXTRA;
+						ffloorflags |= FOF_CUTEXTRA|FOF_EXTRA;
 					else
-						ffloorflags |= FF_CUTLEVEL;
+						ffloorflags |= FOF_CUTLEVEL;
 				}
 
 				P_AddFakeFloorsByLine(i, lines[i].args[1], lines[i].args[2], ffloorflags, secthinkers);
 				break;
 
 			case 120: // FOF (water)
-				ffloorflags = FF_EXISTS|FF_RENDERPLANES|FF_SWIMMABLE|FF_BOTHPLANES|FF_CUTEXTRA|FF_EXTRA|FF_CUTSPRITES;
+				ffloorflags = FOF_EXISTS|FOF_RENDERPLANES|FOF_SWIMMABLE|FOF_BOTHPLANES|FOF_CUTEXTRA|FOF_EXTRA|FOF_CUTSPRITES;
 				if (!(lines[i].args[3] & TMFW_NOSIDES))
-					ffloorflags |= FF_RENDERSIDES|FF_ALLSIDES;
+					ffloorflags |= FOF_RENDERSIDES|FOF_ALLSIDES;
 				if (lines[i].args[3] & TMFW_DOUBLESHADOW)
-					ffloorflags |= FF_DOUBLESHADOW;
+					ffloorflags |= FOF_DOUBLESHADOW;
 				if (lines[i].args[3] & TMFW_COLORMAPONLY)
-					ffloorflags |= FF_COLORMAPONLY;
+					ffloorflags |= FOF_COLORMAPONLY;
 				if (!(lines[i].args[3] & TMFW_NORIPPLE))
-					ffloorflags |= FF_RIPPLE;
+					ffloorflags |= FOF_RIPPLE;
 				if (lines[i].args[3] & TMFW_GOOWATER)
-					ffloorflags |= FF_GOOWATER;
+					ffloorflags |= FOF_GOOWATER;
 				if (lines[i].args[3] & TMFW_SPLAT)
-					ffloorflags |= FF_SPLAT;
+					ffloorflags |= FOF_SPLAT;
 				P_AddFakeFloorsByLine(i, lines[i].args[1], lines[i].args[2], ffloorflags, secthinkers);
 				break;
 
 			case 150: // FOF (Air bobbing)
-				P_AddFakeFloorsByLine(i, 0xff, TMB_TRANSLUCENT, FF_EXISTS|FF_SOLID|FF_RENDERALL, secthinkers);
+				P_AddFakeFloorsByLine(i, 0xff, TMB_TRANSLUCENT, FOF_EXISTS|FOF_SOLID|FOF_RENDERALL, secthinkers);
 				P_AddAirbob(lines[i].frontsector, lines[i].args[0], lines[i].args[1] << FRACBITS, !!(lines[i].args[2] & TMFB_REVERSE), !!(lines[i].args[2] & TMFB_SPINDASH), !!(lines[i].args[2] & TMFB_DYNAMIC));
 				break;
 
 			case 160: // FOF (Water bobbing)
-				P_AddFakeFloorsByLine(i, 0xff, TMB_TRANSLUCENT, FF_EXISTS|FF_SOLID|FF_RENDERALL|FF_FLOATBOB, secthinkers);
+				P_AddFakeFloorsByLine(i, 0xff, TMB_TRANSLUCENT, FOF_EXISTS|FOF_SOLID|FOF_RENDERALL|FOF_FLOATBOB, secthinkers);
 				break;
 
 			case 170: // FOF (Crumbling)
-				ffloorflags = FF_EXISTS|FF_SOLID|FF_RENDERALL|FF_CRUMBLE;
+				ffloorflags = FOF_EXISTS|FOF_SOLID|FOF_RENDERALL|FOF_CRUMBLE;
 
 				//Tangibility settings
 				if (lines[i].args[3] & TMFT_INTANGIBLETOP)
-					ffloorflags |= FF_REVERSEPLATFORM;
+					ffloorflags |= FOF_REVERSEPLATFORM;
 				if (lines[i].args[3] & TMFT_INTANGIBLEBOTTOM)
-					ffloorflags |= FF_PLATFORM;
+					ffloorflags |= FOF_PLATFORM;
 				if (lines[i].args[3] & TMFT_DONTBLOCKPLAYER)
-					ffloorflags &= ~FF_BLOCKPLAYER;
+					ffloorflags &= ~FOF_BLOCKPLAYER;
 				if (lines[i].args[3] & TMFT_DONTBLOCKOTHERS)
-					ffloorflags &= ~FF_BLOCKOTHERS;
+					ffloorflags &= ~FOF_BLOCKOTHERS;
 
 				//Flags
 				if (lines[i].args[4] & TMFC_NOSHADE)
-					ffloorflags |= FF_NOSHADE;
+					ffloorflags |= FOF_NOSHADE;
 				if (lines[i].args[4] & TMFC_NORETURN)
-					ffloorflags |= FF_NORETURN;
+					ffloorflags |= FOF_NORETURN;
 				if (lines[i].args[4] & TMFC_FLOATBOB)
-					ffloorflags |= FF_FLOATBOB;
+					ffloorflags |= FOF_FLOATBOB;
 				if (lines[i].args[4] & TMFC_SPLAT)
-					ffloorflags |= FF_SPLAT;
+					ffloorflags |= FOF_SPLAT;
 
 				//If translucent or player can enter it, cut inner walls
 				if (lines[i].args[1] < 0xff || (lines[i].args[3] & TMFT_VISIBLEFROMINSIDE))
-					ffloorflags |= FF_CUTEXTRA|FF_EXTRA;
+					ffloorflags |= FOF_CUTEXTRA|FOF_EXTRA;
 				else
-					ffloorflags |= FF_CUTLEVEL;
+					ffloorflags |= FOF_CUTLEVEL;
 
 				//If player can enter it, render insides
 				if (lines[i].args[3] & TMFT_VISIBLEFROMINSIDE)
 				{
-					if (ffloorflags & FF_RENDERPLANES)
-						ffloorflags |= FF_BOTHPLANES;
-					if (ffloorflags & FF_RENDERSIDES)
-						ffloorflags |= FF_ALLSIDES;
+					if (ffloorflags & FOF_RENDERPLANES)
+						ffloorflags |= FOF_BOTHPLANES;
+					if (ffloorflags & FOF_RENDERSIDES)
+						ffloorflags |= FOF_ALLSIDES;
 				}
 
 				P_AddFakeFloorsByLine(i, lines[i].args[1], lines[i].args[2], ffloorflags, secthinkers);
@@ -6590,50 +6590,50 @@ void P_SpawnSpecials(boolean fromnetsave)
 				fixed_t ceilingtop = P_FindHighestCeilingSurrounding(lines[i].frontsector);
 				fixed_t ceilingbottom = P_FindLowestCeilingSurrounding(lines[i].frontsector);
 
-				ffloorflags = FF_EXISTS|FF_SOLID|FF_RENDERALL;
+				ffloorflags = FOF_EXISTS|FOF_SOLID|FOF_RENDERALL;
 
 				//Appearance settings
 				if (lines[i].args[3] & TMFA_NOPLANES)
-					ffloorflags &= ~FF_RENDERPLANES;
+					ffloorflags &= ~FOF_RENDERPLANES;
 				if (lines[i].args[3] & TMFA_NOSIDES)
-					ffloorflags &= ~FF_RENDERSIDES;
+					ffloorflags &= ~FOF_RENDERSIDES;
 				if (lines[i].args[3] & TMFA_INSIDES)
 				{
-					if (ffloorflags & FF_RENDERPLANES)
-						ffloorflags |= FF_BOTHPLANES;
-					if (ffloorflags & FF_RENDERSIDES)
-						ffloorflags |= FF_ALLSIDES;
+					if (ffloorflags & FOF_RENDERPLANES)
+						ffloorflags |= FOF_BOTHPLANES;
+					if (ffloorflags & FOF_RENDERSIDES)
+						ffloorflags |= FOF_ALLSIDES;
 				}
 				if (lines[i].args[3] & TMFA_ONLYINSIDES)
 				{
-					if (ffloorflags & FF_RENDERPLANES)
-						ffloorflags |= FF_INVERTPLANES;
-					if (ffloorflags & FF_RENDERSIDES)
-						ffloorflags |= FF_INVERTSIDES;
+					if (ffloorflags & FOF_RENDERPLANES)
+						ffloorflags |= FOF_INVERTPLANES;
+					if (ffloorflags & FOF_RENDERSIDES)
+						ffloorflags |= FOF_INVERTSIDES;
 				}
 				if (lines[i].args[3] & TMFA_NOSHADE)
-					ffloorflags |= FF_NOSHADE;
+					ffloorflags |= FOF_NOSHADE;
 				if (lines[i].args[3] & TMFA_SPLAT)
-					ffloorflags |= FF_SPLAT;
+					ffloorflags |= FOF_SPLAT;
 
 				//Tangibility settings
 				if (lines[i].args[4] & TMFT_INTANGIBLETOP)
-					ffloorflags |= FF_REVERSEPLATFORM;
+					ffloorflags |= FOF_REVERSEPLATFORM;
 				if (lines[i].args[4] & TMFT_INTANGIBLEBOTTOM)
-					ffloorflags |= FF_PLATFORM;
+					ffloorflags |= FOF_PLATFORM;
 				if (lines[i].args[4] & TMFT_DONTBLOCKPLAYER)
-					ffloorflags &= ~FF_BLOCKPLAYER;
+					ffloorflags &= ~FOF_BLOCKPLAYER;
 				if (lines[i].args[4] & TMFT_DONTBLOCKOTHERS)
-					ffloorflags &= ~FF_BLOCKOTHERS;
+					ffloorflags &= ~FOF_BLOCKOTHERS;
 
 				//Cutting options
-				if (ffloorflags & FF_RENDERALL)
+				if (ffloorflags & FOF_RENDERALL)
 				{
 					//If translucent or player can enter it, cut inner walls
 					if ((lines[i].args[1] < 255) || (lines[i].args[4] & TMFT_VISIBLEFROMINSIDE))
-						ffloorflags |= FF_CUTEXTRA|FF_EXTRA;
+						ffloorflags |= FOF_CUTEXTRA|FOF_EXTRA;
 					else
-						ffloorflags |= FF_CUTLEVEL;
+						ffloorflags |= FOF_CUTLEVEL;
 				}
 
 				P_AddFakeFloorsByLine(i, lines[i].args[1], lines[i].args[2], ffloorflags, secthinkers);
@@ -6641,14 +6641,14 @@ void P_SpawnSpecials(boolean fromnetsave)
 				break;
 			}
 			case 200: // Light block
-				ffloorflags = FF_EXISTS|FF_CUTSPRITES;
+				ffloorflags = FOF_EXISTS|FOF_CUTSPRITES;
 				if (!lines[i].args[1])
-					ffloorflags |= FF_DOUBLESHADOW;
+					ffloorflags |= FOF_DOUBLESHADOW;
 				P_AddFakeFloorsByLine(i, 0xff, TMB_TRANSLUCENT, ffloorflags, secthinkers);
 				break;
 
 			case 202: // Fog
-				ffloorflags = FF_EXISTS|FF_RENDERALL|FF_FOG|FF_INVERTPLANES|FF_INVERTSIDES|FF_CUTEXTRA|FF_EXTRA|FF_DOUBLESHADOW|FF_CUTSPRITES;
+				ffloorflags = FOF_EXISTS|FOF_RENDERALL|FOF_FOG|FOF_INVERTPLANES|FOF_INVERTSIDES|FOF_CUTEXTRA|FOF_EXTRA|FOF_DOUBLESHADOW|FOF_CUTSPRITES;
 				sec = sides[*lines[i].sidenum].sector - sectors;
 				// SoM: Because it's fog, check for an extra colormap and set the fog flag...
 				if (sectors[sec].extra_colormap)
@@ -6657,45 +6657,45 @@ void P_SpawnSpecials(boolean fromnetsave)
 				break;
 
 			case 220: //Intangible
-				ffloorflags = FF_EXISTS|FF_RENDERALL|FF_CUTEXTRA|FF_EXTRA|FF_CUTSPRITES;
+				ffloorflags = FOF_EXISTS|FOF_RENDERALL|FOF_CUTEXTRA|FOF_EXTRA|FOF_CUTSPRITES;
 
 				//Appearance settings
 				if (lines[i].args[3] & TMFA_NOPLANES)
-					ffloorflags &= ~FF_RENDERPLANES;
+					ffloorflags &= ~FOF_RENDERPLANES;
 				if (lines[i].args[3] & TMFA_NOSIDES)
-					ffloorflags &= ~FF_RENDERSIDES;
+					ffloorflags &= ~FOF_RENDERSIDES;
 				if (!(lines[i].args[3] & TMFA_INSIDES))
 				{
-					if (ffloorflags & FF_RENDERPLANES)
-						ffloorflags |= FF_BOTHPLANES;
-					if (ffloorflags & FF_RENDERSIDES)
-						ffloorflags |= FF_ALLSIDES;
+					if (ffloorflags & FOF_RENDERPLANES)
+						ffloorflags |= FOF_BOTHPLANES;
+					if (ffloorflags & FOF_RENDERSIDES)
+						ffloorflags |= FOF_ALLSIDES;
 				}
 				if (lines[i].args[3] & TMFA_ONLYINSIDES)
 				{
-					if (ffloorflags & FF_RENDERPLANES)
-						ffloorflags |= FF_INVERTPLANES;
-					if (ffloorflags & FF_RENDERSIDES)
-						ffloorflags |= FF_INVERTSIDES;
+					if (ffloorflags & FOF_RENDERPLANES)
+						ffloorflags |= FOF_INVERTPLANES;
+					if (ffloorflags & FOF_RENDERSIDES)
+						ffloorflags |= FOF_INVERTSIDES;
 				}
 				if (lines[i].args[3] & TMFA_NOSHADE)
-					ffloorflags |= FF_NOSHADE;
+					ffloorflags |= FOF_NOSHADE;
 				if (lines[i].args[3] & TMFA_SPLAT)
-					ffloorflags |= FF_SPLAT;
+					ffloorflags |= FOF_SPLAT;
 
 				P_AddFakeFloorsByLine(i, lines[i].args[1], lines[i].args[2], ffloorflags, secthinkers);
 				break;
 
 			case 223: // FOF (intangible, invisible) - for combining specials in a sector
-				P_AddFakeFloorsByLine(i, 0xff, TMB_TRANSLUCENT, FF_EXISTS|FF_NOSHADE, secthinkers);
+				P_AddFakeFloorsByLine(i, 0xff, TMB_TRANSLUCENT, FOF_EXISTS|FOF_NOSHADE, secthinkers);
 				break;
 
 			case 250: // Mario Block
-				ffloorflags = FF_EXISTS|FF_SOLID|FF_RENDERALL|FF_CUTLEVEL|FF_MARIO;
+				ffloorflags = FOF_EXISTS|FOF_SOLID|FOF_RENDERALL|FOF_CUTLEVEL|FOF_MARIO;
 				if (lines[i].args[1] & TMFM_BRICK)
-					ffloorflags |= FF_GOOWATER;
+					ffloorflags |= FOF_GOOWATER;
 				if (lines[i].args[1] & TMFM_INVISIBLE)
-					ffloorflags &= ~(FF_SOLID|FF_RENDERALL|FF_CUTLEVEL);
+					ffloorflags &= ~(FOF_SOLID|FOF_RENDERALL|FOF_CUTLEVEL);
 
 				P_AddFakeFloorsByLine(i, 0xff, TMB_TRANSLUCENT, ffloorflags, secthinkers);
 				break;
@@ -6704,7 +6704,7 @@ void P_SpawnSpecials(boolean fromnetsave)
 			{
 				UINT16 sound = (lines[i].stringargs[0]) ? get_number(lines[i].stringargs[0]) : sfx_thwomp;
 				P_AddThwompThinker(lines[i].frontsector, &lines[i], lines[i].args[1] << (FRACBITS - 3), lines[i].args[2] << (FRACBITS - 3), sound);
-				P_AddFakeFloorsByLine(i, 0xff, TMB_TRANSLUCENT, FF_EXISTS|FF_SOLID|FF_RENDERALL|FF_CUTLEVEL, secthinkers);
+				P_AddFakeFloorsByLine(i, 0xff, TMB_TRANSLUCENT, FOF_EXISTS|FOF_SOLID|FOF_RENDERALL|FOF_CUTLEVEL, secthinkers);
 				break;
 			}
 
@@ -6713,7 +6713,7 @@ void P_SpawnSpecials(boolean fromnetsave)
 				UINT8 busttype = BT_REGULAR;
 				ffloorbustflags_e bustflags = 0;
 
-				ffloorflags = FF_EXISTS|FF_BLOCKOTHERS|FF_RENDERALL|FF_BUSTUP;
+				ffloorflags = FOF_EXISTS|FOF_BLOCKOTHERS|FOF_RENDERALL|FOF_BUSTUP;
 
 				//Bustable type
 				switch (lines[i].args[3])
@@ -6740,10 +6740,10 @@ void P_SpawnSpecials(boolean fromnetsave)
 				if (lines[i].args[4] & TMFB_ONLYBOTTOM)
 					bustflags |= FB_ONLYBOTTOM;
 				if (lines[i].args[4] & TMFB_SPLAT)
-					ffloorflags |= FF_SPLAT;
+					ffloorflags |= FOF_SPLAT;
 
 				if (busttype != BT_TOUCH || bustflags & FB_ONLYBOTTOM)
-					ffloorflags |= FF_BLOCKPLAYER;
+					ffloorflags |= FOF_BLOCKPLAYER;
 
 				TAG_ITER_SECTORS(lines[i].args[0], s)
 				{
@@ -6757,9 +6757,9 @@ void P_SpawnSpecials(boolean fromnetsave)
 				break;
 			}
 			case 257: // Quicksand
-				ffloorflags = FF_EXISTS|FF_QUICKSAND|FF_RENDERALL|FF_ALLSIDES|FF_CUTSPRITES;
+				ffloorflags = FOF_EXISTS|FOF_QUICKSAND|FOF_RENDERALL|FOF_ALLSIDES|FOF_CUTSPRITES;
 				if (!(lines[i].args[1]))
-					ffloorflags |= FF_RIPPLE;
+					ffloorflags |= FOF_RIPPLE;
 
 				TAG_ITER_SECTORS(lines[i].args[0], s)
 				{
@@ -6772,10 +6772,10 @@ void P_SpawnSpecials(boolean fromnetsave)
 				break;
 
 			case 258: // Laser block
-				ffloorflags = FF_EXISTS|FF_RENDERALL|FF_NOSHADE|FF_EXTRA|FF_CUTEXTRA|FF_TRANSLUCENT;
+				ffloorflags = FOF_EXISTS|FOF_RENDERALL|FOF_NOSHADE|FOF_EXTRA|FOF_CUTEXTRA|FOF_TRANSLUCENT;
 				P_AddLaserThinker(lines[i].args[0], lines + i, !!(lines[i].args[3] & TMFL_NOBOSSES));
 				if (lines[i].args[3] & TMFL_SPLAT)
-					ffloorflags |= FF_SPLAT;
+					ffloorflags |= FOF_SPLAT;
 				P_AddFakeFloorsByLine(i, lines[i].args[1], lines[i].args[2], ffloorflags, secthinkers);
 				break;
 
@@ -6787,12 +6787,12 @@ void P_SpawnSpecials(boolean fromnetsave)
 						continue;
 					if (!udmf) // Ugly backwards compatibility stuff
 					{
-						if (lines[i].args[3] & FF_QUICKSAND)
+						if (lines[i].args[3] & FOF_QUICKSAND)
 						{
 							fflr->sinkspeed = abs(lines[i].dx) >> 1;
 							fflr->friction = abs(lines[i].dy) >> 6;
 						}
-						if (lines[i].args[3] & FF_BUSTUP)
+						if (lines[i].args[3] & FOF_BUSTUP)
 						{
 							switch (lines[i].args[4] % TMFB_ONLYBOTTOM)
 							{
@@ -6835,31 +6835,31 @@ void P_SpawnSpecials(boolean fromnetsave)
 					if (dtype == 0)
 						dtype = 1;
 
-					ffloorflags = FF_EXISTS;
+					ffloorflags = FOF_EXISTS;
 
-					if (dflags2 & 1) ffloorflags |= FF_NOSHADE; // Disable light effects (Means no shadowcast)
-					if (dflags2 & 2) ffloorflags |= FF_DOUBLESHADOW; // Restrict light inside (Means doubleshadow)
+					if (dflags2 & 1) ffloorflags |= FOF_NOSHADE; // Disable light effects (Means no shadowcast)
+					if (dflags2 & 2) ffloorflags |= FOF_DOUBLESHADOW; // Restrict light inside (Means doubleshadow)
 					if (dflags2 & 4) isfog = true; // Fog effect (Explicitly render like a fog block)
 
-					if (dflags1 & 4) ffloorflags |= FF_BOTHPLANES|FF_ALLSIDES; // Render-inside
-					if (dflags1 & 16) ffloorflags |= FF_INVERTSIDES|FF_INVERTPLANES; // Invert visibility rules
+					if (dflags1 & 4) ffloorflags |= FOF_BOTHPLANES|FOF_ALLSIDES; // Render-inside
+					if (dflags1 & 16) ffloorflags |= FOF_INVERTSIDES|FOF_INVERTPLANES; // Invert visibility rules
 
 					// Fog block
 					if (isfog)
-						ffloorflags |= FF_RENDERALL|FF_CUTEXTRA|FF_CUTSPRITES|FF_BOTHPLANES|FF_EXTRA|FF_FOG|FF_INVERTPLANES|FF_ALLSIDES|FF_INVERTSIDES;
+						ffloorflags |= FOF_RENDERALL|FOF_CUTEXTRA|FOF_CUTSPRITES|FOF_BOTHPLANES|FOF_EXTRA|FOF_FOG|FOF_INVERTPLANES|FOF_ALLSIDES|FOF_INVERTSIDES;
 					else
 					{
-						ffloorflags |= FF_RENDERALL;
+						ffloorflags |= FOF_RENDERALL;
 
 						// Solid
 						if (dtype == 1)
-							ffloorflags |= FF_SOLID|FF_CUTLEVEL;
+							ffloorflags |= FOF_SOLID|FOF_CUTLEVEL;
 						// Water
 						else if (dtype == 2)
-							ffloorflags |= FF_SWIMMABLE|FF_CUTEXTRA|FF_CUTSPRITES|FF_EXTRA|FF_RIPPLE;
+							ffloorflags |= FOF_SWIMMABLE|FOF_CUTEXTRA|FOF_CUTSPRITES|FOF_EXTRA|FOF_RIPPLE;
 						// Intangible
 						else if (dtype == 3)
-							ffloorflags |= FF_CUTEXTRA|FF_CUTSPRITES|FF_EXTRA;
+							ffloorflags |= FOF_CUTEXTRA|FOF_CUTSPRITES|FOF_EXTRA;
 					}
 
 					// Non-opaque
@@ -6869,19 +6869,19 @@ void P_SpawnSpecials(boolean fromnetsave)
 						if (dopacity == 0)
 						{
 							// True invisible
-							if (ffloorflags & FF_NOSHADE)
-								ffloorflags &= ~(FF_RENDERALL|FF_CUTEXTRA|FF_CUTSPRITES|FF_EXTRA|FF_BOTHPLANES|FF_ALLSIDES|FF_CUTLEVEL);
+							if (ffloorflags & FOF_NOSHADE)
+								ffloorflags &= ~(FOF_RENDERALL|FOF_CUTEXTRA|FOF_CUTSPRITES|FOF_EXTRA|FOF_BOTHPLANES|FOF_ALLSIDES|FOF_CUTLEVEL);
 							// Shadow block
 							else
 							{
-								ffloorflags |= FF_CUTSPRITES;
-								ffloorflags &= ~(FF_RENDERALL|FF_CUTEXTRA|FF_EXTRA|FF_BOTHPLANES|FF_ALLSIDES|FF_CUTLEVEL);
+								ffloorflags |= FOF_CUTSPRITES;
+								ffloorflags &= ~(FOF_RENDERALL|FOF_CUTEXTRA|FOF_EXTRA|FOF_BOTHPLANES|FOF_ALLSIDES|FOF_CUTLEVEL);
 							}
 						}
 						else
 						{
-							ffloorflags |= FF_TRANSLUCENT|FF_CUTEXTRA|FF_EXTRA;
-							ffloorflags &= ~FF_CUTLEVEL;
+							ffloorflags |= FOF_TRANSLUCENT|FOF_CUTEXTRA|FOF_EXTRA;
+							ffloorflags &= ~FOF_CUTLEVEL;
 						}
 					}
 
@@ -7073,8 +7073,8 @@ void P_SpawnSpecials(boolean fromnetsave)
 							if (rover->master != lines + l)
 								continue;
 
-							rover->flags |= FF_BUSTUP;
-							rover->spawnflags |= FF_BUSTUP;
+							rover->fofflags |= FOF_BUSTUP;
+							rover->spawnflags |= FOF_BUSTUP;
 							rover->bustflags = bustflags;
 							rover->busttype = busttype;
 							rover->busttag = lines[i].args[3];
@@ -7104,8 +7104,8 @@ void P_SpawnSpecials(boolean fromnetsave)
 							if (rover->master != lines + l)
 								continue;
 
-							rover->flags |= FF_QUICKSAND;
-							rover->spawnflags |= FF_QUICKSAND;
+							rover->fofflags |= FOF_QUICKSAND;
+							rover->spawnflags |= FOF_QUICKSAND;
 							rover->sinkspeed = abs(lines[i].args[1]) << (FRACBITS - 1);
 							rover->friction = abs(lines[i].args[2]) << (FRACBITS - 6);
 							CheckForQuicksand = true;
@@ -7348,7 +7348,7 @@ void T_Scroll(scroll_t *s)
 					if (!rover) // This should be impossible, but don't complain if it is the case somehow
 						continue;
 
-					if (!(rover->flags & FF_EXISTS)) // If the FOF does not "exist", we pretend that nobody's there
+					if (!(rover->fofflags & FOF_EXISTS)) // If the FOF does not "exist", we pretend that nobody's there
 						continue;
 
 					for (node = psec->touching_thinglist; node; node = node->m_thinglist_next)
@@ -7423,7 +7423,7 @@ void T_Scroll(scroll_t *s)
 					if (!rover) // This should be impossible, but don't complain if it is the case somehow
 						continue;
 
-					if (!(rover->flags & FF_EXISTS)) // If the FOF does not "exist", we pretend that nobody's there
+					if (!(rover->fofflags & FOF_EXISTS)) // If the FOF does not "exist", we pretend that nobody's there
 						continue;
 
 					for (node = psec->touching_thinglist; node; node = node->m_thinglist_next)
@@ -7640,10 +7640,10 @@ void T_Disappear(disappear_t *d)
 					continue;
 
 				if (d->exists)
-					rover->flags &= ~FF_EXISTS;
+					rover->fofflags &= ~FOF_EXISTS;
 				else
 				{
-					rover->flags |= FF_EXISTS;
+					rover->fofflags |= FOF_EXISTS;
 
 					if (!(lines[d->sourceline].args[5]))
 					{
@@ -7728,11 +7728,11 @@ static boolean P_FadeFakeFloor(ffloor_t *rover, INT16 sourcevalue, INT16 destval
 	// If fading an invisible FOF whose render flags we did not yet set,
 	// initialize its alpha to 1
 	if (dotranslucent &&
-		(rover->spawnflags & FF_NOSHADE) && // do not include light blocks, which don't set FF_NOSHADE
-		!(rover->flags & FF_FOG) && // do not include fog
-		!(rover->spawnflags & FF_RENDERSIDES) &&
-		!(rover->spawnflags & FF_RENDERPLANES) &&
-		!(rover->flags & FF_RENDERALL))
+		(rover->spawnflags & FOF_NOSHADE) && // do not include light blocks, which don't set FOF_NOSHADE
+		!(rover->fofflags & FOF_FOG) && // do not include fog
+		!(rover->spawnflags & FOF_RENDERSIDES) &&
+		!(rover->spawnflags & FOF_RENDERPLANES) &&
+		!(rover->fofflags & FOF_RENDERALL))
 		rover->alpha = 1;
 
 	if (fadingdata)
@@ -7753,16 +7753,16 @@ static boolean P_FadeFakeFloor(ffloor_t *rover, INT16 sourcevalue, INT16 destval
 
 			if (docollision)
 			{
-				if (rover->spawnflags & FF_SOLID)
-					rover->flags &= ~FF_SOLID;
-				if (rover->spawnflags & FF_SWIMMABLE)
-					rover->flags &= ~FF_SWIMMABLE;
-				if (rover->spawnflags & FF_QUICKSAND)
-					rover->flags &= ~FF_QUICKSAND;
-				if (rover->spawnflags & FF_BUSTUP)
-					rover->flags &= ~FF_BUSTUP;
-				if (rover->spawnflags & FF_MARIO)
-					rover->flags &= ~FF_MARIO;
+				if (rover->spawnflags & FOF_SOLID)
+					rover->fofflags &= ~FOF_SOLID;
+				if (rover->spawnflags & FOF_SWIMMABLE)
+					rover->fofflags &= ~FOF_SWIMMABLE;
+				if (rover->spawnflags & FOF_QUICKSAND)
+					rover->fofflags &= ~FOF_QUICKSAND;
+				if (rover->spawnflags & FOF_BUSTUP)
+					rover->fofflags &= ~FOF_BUSTUP;
+				if (rover->spawnflags & FOF_MARIO)
+					rover->fofflags &= ~FOF_MARIO;
 			}
 		}
 		else // continue fading out
@@ -7788,16 +7788,16 @@ static boolean P_FadeFakeFloor(ffloor_t *rover, INT16 sourcevalue, INT16 destval
 
 			if (docollision)
 			{
-				if (rover->spawnflags & FF_SOLID)
-					rover->flags |= FF_SOLID;
-				if (rover->spawnflags & FF_SWIMMABLE)
-					rover->flags |= FF_SWIMMABLE;
-				if (rover->spawnflags & FF_QUICKSAND)
-					rover->flags |= FF_QUICKSAND;
-				if (rover->spawnflags & FF_BUSTUP)
-					rover->flags |= FF_BUSTUP;
-				if (rover->spawnflags & FF_MARIO)
-					rover->flags |= FF_MARIO;
+				if (rover->spawnflags & FOF_SOLID)
+					rover->fofflags |= FOF_SOLID;
+				if (rover->spawnflags & FOF_SWIMMABLE)
+					rover->fofflags |= FOF_SWIMMABLE;
+				if (rover->spawnflags & FOF_QUICKSAND)
+					rover->fofflags |= FOF_QUICKSAND;
+				if (rover->spawnflags & FOF_BUSTUP)
+					rover->fofflags |= FOF_BUSTUP;
+				if (rover->spawnflags & FOF_MARIO)
+					rover->fofflags |= FOF_MARIO;
 			}
 		}
 		else // continue fading in
@@ -7817,114 +7817,114 @@ static boolean P_FadeFakeFloor(ffloor_t *rover, INT16 sourcevalue, INT16 destval
 	// routines common to both fade in and fade out
 	if (!stillfading)
 	{
-		if (doexists && !(rover->spawnflags & FF_BUSTUP))
+		if (doexists && !(rover->spawnflags & FOF_BUSTUP))
 		{
 			if (alpha <= 1)
-				rover->flags &= ~FF_EXISTS;
+				rover->fofflags &= ~FOF_EXISTS;
 			else
-				rover->flags |= FF_EXISTS;
+				rover->fofflags |= FOF_EXISTS;
 
 			// Re-render lighting at end of fade
-			if (dolighting && !(rover->spawnflags & FF_NOSHADE) && !(rover->flags & FF_EXISTS))
+			if (dolighting && !(rover->spawnflags & FOF_NOSHADE) && !(rover->fofflags & FOF_EXISTS))
 				rover->target->moved = true;
 		}
 
-		if (dotranslucent && !(rover->flags & FF_FOG))
+		if (dotranslucent && !(rover->fofflags & FOF_FOG))
 		{
 			if (alpha >= 256)
 			{
-				if (!(rover->flags & FF_CUTSOLIDS) &&
-					(rover->spawnflags & FF_CUTSOLIDS))
+				if (!(rover->fofflags & FOF_CUTSOLIDS) &&
+					(rover->spawnflags & FOF_CUTSOLIDS))
 				{
-					rover->flags |= FF_CUTSOLIDS;
+					rover->fofflags |= FOF_CUTSOLIDS;
 					rover->target->moved = true;
 				}
 
-				rover->flags &= ~FF_TRANSLUCENT;
+				rover->fofflags &= ~FOF_TRANSLUCENT;
 			}
 			else
 			{
-				rover->flags |= FF_TRANSLUCENT;
+				rover->fofflags |= FOF_TRANSLUCENT;
 
-				if ((rover->flags & FF_CUTSOLIDS) &&
-					(rover->spawnflags & FF_CUTSOLIDS))
+				if ((rover->fofflags & FOF_CUTSOLIDS) &&
+					(rover->spawnflags & FOF_CUTSOLIDS))
 				{
-					rover->flags &= ~FF_CUTSOLIDS;
+					rover->fofflags &= ~FOF_CUTSOLIDS;
 					rover->target->moved = true;
 				}
 			}
 
-			if ((rover->spawnflags & FF_NOSHADE) && // do not include light blocks, which don't set FF_NOSHADE
-				!(rover->spawnflags & FF_RENDERSIDES) &&
-				!(rover->spawnflags & FF_RENDERPLANES))
+			if ((rover->spawnflags & FOF_NOSHADE) && // do not include light blocks, which don't set FOF_NOSHADE
+				!(rover->spawnflags & FOF_RENDERSIDES) &&
+				!(rover->spawnflags & FOF_RENDERPLANES))
 			{
 				if (rover->alpha > 1)
-					rover->flags |= FF_RENDERALL;
+					rover->fofflags |= FOF_RENDERALL;
 				else
-					rover->flags &= ~FF_RENDERALL;
+					rover->fofflags &= ~FOF_RENDERALL;
 			}
 		}
 	}
 	else
 	{
-		if (doexists && !(rover->spawnflags & FF_BUSTUP))
+		if (doexists && !(rover->spawnflags & FOF_BUSTUP))
 		{
-			// Re-render lighting if we haven't yet set FF_EXISTS (beginning of fade)
-			if (dolighting && !(rover->spawnflags & FF_NOSHADE) && !(rover->flags & FF_EXISTS))
+			// Re-render lighting if we haven't yet set FOF_EXISTS (beginning of fade)
+			if (dolighting && !(rover->spawnflags & FOF_NOSHADE) && !(rover->fofflags & FOF_EXISTS))
 				rover->target->moved = true;
 
-			rover->flags |= FF_EXISTS;
+			rover->fofflags |= FOF_EXISTS;
 		}
 
-		if (dotranslucent && !(rover->flags & FF_FOG))
+		if (dotranslucent && !(rover->fofflags & FOF_FOG))
 		{
-			rover->flags |= FF_TRANSLUCENT;
+			rover->fofflags |= FOF_TRANSLUCENT;
 
-			if ((rover->flags & FF_CUTSOLIDS) &&
-				(rover->spawnflags & FF_CUTSOLIDS))
+			if ((rover->fofflags & FOF_CUTSOLIDS) &&
+				(rover->spawnflags & FOF_CUTSOLIDS))
 			{
-				rover->flags &= ~FF_CUTSOLIDS;
+				rover->fofflags &= ~FOF_CUTSOLIDS;
 				rover->target->moved = true;
 			}
 
-			if ((rover->spawnflags & FF_NOSHADE) && // do not include light blocks, which don't set FF_NOSHADE
-				!(rover->spawnflags & FF_RENDERSIDES) &&
-				!(rover->spawnflags & FF_RENDERPLANES))
-				rover->flags |= FF_RENDERALL;
+			if ((rover->spawnflags & FOF_NOSHADE) && // do not include light blocks, which don't set FOF_NOSHADE
+				!(rover->spawnflags & FOF_RENDERSIDES) &&
+				!(rover->spawnflags & FOF_RENDERPLANES))
+				rover->fofflags |= FOF_RENDERALL;
 		}
 
 		if (docollision)
 		{
 			if (doghostfade) // remove collision flags during fade
 			{
-				if (rover->spawnflags & FF_SOLID)
-					rover->flags &= ~FF_SOLID;
-				if (rover->spawnflags & FF_SWIMMABLE)
-					rover->flags &= ~FF_SWIMMABLE;
-				if (rover->spawnflags & FF_QUICKSAND)
-					rover->flags &= ~FF_QUICKSAND;
-				if (rover->spawnflags & FF_BUSTUP)
-					rover->flags &= ~FF_BUSTUP;
-				if (rover->spawnflags & FF_MARIO)
-					rover->flags &= ~FF_MARIO;
+				if (rover->spawnflags & FOF_SOLID)
+					rover->fofflags &= ~FOF_SOLID;
+				if (rover->spawnflags & FOF_SWIMMABLE)
+					rover->fofflags &= ~FOF_SWIMMABLE;
+				if (rover->spawnflags & FOF_QUICKSAND)
+					rover->fofflags &= ~FOF_QUICKSAND;
+				if (rover->spawnflags & FOF_BUSTUP)
+					rover->fofflags &= ~FOF_BUSTUP;
+				if (rover->spawnflags & FOF_MARIO)
+					rover->fofflags &= ~FOF_MARIO;
 			}
 			else // keep collision during fade
 			{
-				if (rover->spawnflags & FF_SOLID)
-					rover->flags |= FF_SOLID;
-				if (rover->spawnflags & FF_SWIMMABLE)
-					rover->flags |= FF_SWIMMABLE;
-				if (rover->spawnflags & FF_QUICKSAND)
-					rover->flags |= FF_QUICKSAND;
-				if (rover->spawnflags & FF_BUSTUP)
-					rover->flags |= FF_BUSTUP;
-				if (rover->spawnflags & FF_MARIO)
-					rover->flags |= FF_MARIO;
+				if (rover->spawnflags & FOF_SOLID)
+					rover->fofflags |= FOF_SOLID;
+				if (rover->spawnflags & FOF_SWIMMABLE)
+					rover->fofflags |= FOF_SWIMMABLE;
+				if (rover->spawnflags & FOF_QUICKSAND)
+					rover->fofflags |= FOF_QUICKSAND;
+				if (rover->spawnflags & FOF_BUSTUP)
+					rover->fofflags |= FOF_BUSTUP;
+				if (rover->spawnflags & FOF_MARIO)
+					rover->fofflags |= FOF_MARIO;
 			}
 		}
 	}
 
-	if (!(rover->flags & FF_FOG)) // don't set FOG alpha
+	if (!(rover->fofflags & FOF_FOG)) // don't set FOG alpha
 	{
 		if (!stillfading || exactalpha)
 			rover->alpha = alpha;
@@ -7967,8 +7967,8 @@ static boolean P_FadeFakeFloor(ffloor_t *rover, INT16 sourcevalue, INT16 destval
   * \param speed        speed to fade by
   * \param ticbased     tic-based logic, speed = duration
   * \param relative     Destvalue is relative to rover->alpha
-  * \param doexists	    handle FF_EXISTS
-  * \param dotranslucent handle FF_TRANSLUCENT
+  * \param doexists	    handle FOF_EXISTS
+  * \param dotranslucent handle FOF_TRANSLUCENT
   * \param dolighting  fade FOF light
   * \param docollision handle interactive flags
   * \param doghostfade  no interactive flags during fading
@@ -7984,10 +7984,10 @@ static void P_AddFakeFloorFader(ffloor_t *rover, size_t sectornum, size_t ffloor
 	// If fading an invisible FOF whose render flags we did not yet set,
 	// initialize its alpha to 1
 	if (dotranslucent &&
-		(rover->spawnflags & FF_NOSHADE) && // do not include light blocks, which don't set FF_NOSHADE
-		!(rover->spawnflags & FF_RENDERSIDES) &&
-		!(rover->spawnflags & FF_RENDERPLANES) &&
-		!(rover->flags & FF_RENDERALL))
+		(rover->spawnflags & FOF_NOSHADE) && // do not include light blocks, which don't set FOF_NOSHADE
+		!(rover->spawnflags & FOF_RENDERSIDES) &&
+		!(rover->spawnflags & FOF_RENDERPLANES) &&
+		!(rover->fofflags & FOF_RENDERALL))
 		rover->alpha = 1;
 
 	// already equal, nothing to do
@@ -8028,7 +8028,7 @@ static void P_AddFakeFloorFader(ffloor_t *rover, size_t sectornum, size_t ffloor
 	P_ResetFakeFloorFader(rover, d, false);
 
 	// Set a separate thinker for shadow fading
-	if (dolighting && !(rover->flags & FF_NOSHADE))
+	if (dolighting && !(rover->fofflags & FOF_NOSHADE))
 	{
 		UINT16 lightdelta = abs(sectors[rover->secnum].spawn_lightlevel - rover->target->lightlevel);
 		fixed_t alphapercent = min(FixedDiv(d->destvalue, rover->spawnalpha), 1*FRACUNIT); // don't make darker than spawn_lightlevel
@@ -8049,7 +8049,7 @@ static void P_AddFakeFloorFader(ffloor_t *rover, size_t sectornum, size_t ffloor
 		d->destlightlevel = -1;
 
 	// Set a separate thinker for colormap fading
-	if (docolormap && !(rover->flags & FF_NOSHADE) && sectors[rover->secnum].spawn_extra_colormap && !sectors[rover->secnum].colormap_protected)
+	if (docolormap && !(rover->fofflags & FOF_NOSHADE) && sectors[rover->secnum].spawn_extra_colormap && !sectors[rover->secnum].colormap_protected)
 	{
 		extracolormap_t *dest_exc,
 			*source_exc = sectors[rover->secnum].extra_colormap ? sectors[rover->secnum].extra_colormap : R_GetDefaultColormap();
@@ -8110,11 +8110,11 @@ void T_Fade(fade_t *d)
 		d->doexists, d->dotranslucent, d->dolighting, d->docolormap, d->docollision, d->doghostfade, d->exactalpha))
 	{
 		// Finalize lighting, copypasta from P_AddFakeFloorFader
-		if (d->dolighting && !(d->rover->flags & FF_NOSHADE) && d->destlightlevel > -1)
+		if (d->dolighting && !(d->rover->fofflags & FOF_NOSHADE) && d->destlightlevel > -1)
 			sectors[d->rover->secnum].lightlevel = d->destlightlevel;
 
 		// Finalize colormap
-		if (d->docolormap && !(d->rover->flags & FF_NOSHADE) && sectors[d->rover->secnum].spawn_extra_colormap)
+		if (d->docolormap && !(d->rover->fofflags & FOF_NOSHADE) && sectors[d->rover->secnum].spawn_extra_colormap)
 			sectors[d->rover->secnum].extra_colormap = d->dest_exc;
 
 		P_RemoveFakeFloorFader(d->rover);
diff --git a/src/p_spec.h b/src/p_spec.h
index 33d18d63e5aeef7ddf955406045655d70755c64b..69c629c4783ad3680e13f25a79b75b053b9f4f07 100644
--- a/src/p_spec.h
+++ b/src/p_spec.h
@@ -1029,8 +1029,8 @@ typedef struct
 	INT16 speed;        ///< Speed to fade by
 	boolean ticbased;    ///< Tic-based logic toggle
 	INT32 timer;        ///< Timer for tic-based logic
-	boolean doexists;   ///< Handle FF_EXISTS
-	boolean dotranslucent; ///< Handle FF_TRANSLUCENT
+	boolean doexists;   ///< Handle FOF_EXISTS
+	boolean dotranslucent; ///< Handle FOF_TRANSLUCENT
 	boolean dolighting; ///< Handle shadows and light blocks
 	boolean docolormap; ///< Handle colormaps
 	boolean docollision; ///< Handle interactive flags
diff --git a/src/p_user.c b/src/p_user.c
index cc5caedd69a03dc47b667b2ca9056897ca0e12b1..fa42568cad316519ea09fdab2da736b09a7291d8 100644
--- a/src/p_user.c
+++ b/src/p_user.c
@@ -2209,7 +2209,7 @@ boolean P_InSpaceSector(mobj_t *mo) // Returns true if you are in space
 
 		for (rover = sector->ffloors; rover; rover = rover->next)
 		{
-			if (!(rover->flags & FF_EXISTS))
+			if (!(rover->fofflags & FOF_EXISTS))
 				continue;
 
 			if (!(rover->master->frontsector->specialflags & SSF_OUTERSPACE))
@@ -2462,10 +2462,10 @@ boolean P_InQuicksand(mobj_t *mo) // Returns true if you are in quicksand
 
 		for (rover = sector->ffloors; rover; rover = rover->next)
 		{
-			if (!(rover->flags & FF_EXISTS))
+			if (!(rover->fofflags & FOF_EXISTS))
 				continue;
 
-			if (!(rover->flags & FF_QUICKSAND))
+			if (!(rover->fofflags & FOF_QUICKSAND))
 				continue;
 
 			topheight    = P_GetFFloorTopZAt   (rover, mo->x, mo->y);
@@ -2486,10 +2486,10 @@ boolean P_InQuicksand(mobj_t *mo) // Returns true if you are in quicksand
 
 static boolean P_PlayerCanBust(player_t *player, ffloor_t *rover)
 {
-	if (!(rover->flags & FF_EXISTS))
+	if (!(rover->fofflags & FOF_EXISTS))
 		return false;
 
-	if (!(rover->flags & FF_BUSTUP))
+	if (!(rover->fofflags & FOF_BUSTUP))
 		return false;
 
 	/*if (rover->master->frontsector->crumblestate != CRUMBLE_NONE)
@@ -2701,17 +2701,17 @@ static void P_CheckBouncySectors(player_t *player)
 		{
 			fixed_t topheight, bottomheight;
 
-			if (!(rover->flags & FF_EXISTS))
+			if (!(rover->fofflags & FOF_EXISTS))
 				continue; // FOFs should not be bouncy if they don't even "exist"
 
 			// Handle deprecated bouncy FOF sector type
 			if (!udmf && GETSECSPECIAL(rover->master->frontsector->special, 1) == 15)
 			{
-				rover->flags |= FF_BOUNCY;
+				rover->fofflags |= FOF_BOUNCY;
 				rover->bouncestrength = P_AproxDistance(rover->master->dx, rover->master->dy)/100;
 			}
 
-			if (!(rover->flags & FF_BOUNCY))
+			if (!(rover->fofflags & FOF_BOUNCY))
 				continue;
 
 			topheight = P_GetFOFTopZ(player->mo, node->m_sector, rover, player->mo->x, player->mo->y, NULL);
@@ -2784,9 +2784,9 @@ static void P_CheckQuicksand(player_t *player)
 
 	for (rover = player->mo->subsector->sector->ffloors; rover; rover = rover->next)
 	{
-		if (!(rover->flags & FF_EXISTS)) continue;
+		if (!(rover->fofflags & FOF_EXISTS)) continue;
 
-		if (!(rover->flags & FF_QUICKSAND))
+		if (!(rover->fofflags & FOF_QUICKSAND))
 			continue;
 
 		topheight    = P_GetFFloorTopZAt   (rover, player->mo->x, player->mo->y);
@@ -3136,7 +3136,7 @@ static void P_DoClimbing(player_t *player)
 
 				for (rover = glidesector->sector->ffloors; rover; rover = rover->next)
 				{
-					if (!(rover->flags & FF_EXISTS) || !(rover->flags & FF_BLOCKPLAYER) || ((rover->flags & FF_BUSTUP) && (player->charflags & SF_CANBUSTWALLS)))
+					if (!(rover->fofflags & FOF_EXISTS) || !(rover->fofflags & FOF_BLOCKPLAYER) || ((rover->fofflags & FOF_BUSTUP) && (player->charflags & SF_CANBUSTWALLS)))
 						continue;
 
 					floorclimb = true;
@@ -3177,7 +3177,7 @@ static void P_DoClimbing(player_t *player)
 							// Is there a FOF directly below this one that we can move onto?
 							for (roverbelow = glidesector->sector->ffloors; roverbelow; roverbelow = roverbelow->next)
 							{
-								if (!(roverbelow->flags & FF_EXISTS) || !(roverbelow->flags & FF_BLOCKPLAYER) || ((rover->flags & FF_BUSTUP) && (player->charflags & SF_CANBUSTWALLS)))
+								if (!(roverbelow->fofflags & FOF_EXISTS) || !(roverbelow->fofflags & FOF_BLOCKPLAYER) || ((rover->fofflags & FOF_BUSTUP) && (player->charflags & SF_CANBUSTWALLS)))
 									continue;
 
 								if (roverbelow == rover)
@@ -3222,7 +3222,7 @@ static void P_DoClimbing(player_t *player)
 							// Is there a FOF directly below this one that we can move onto?
 							for (roverbelow = glidesector->sector->ffloors; roverbelow; roverbelow = roverbelow->next)
 							{
-								if (!(roverbelow->flags & FF_EXISTS) || !(roverbelow->flags & FF_BLOCKPLAYER) || ((rover->flags & FF_BUSTUP) && (player->charflags & SF_CANBUSTWALLS)))
+								if (!(roverbelow->fofflags & FOF_EXISTS) || !(roverbelow->fofflags & FOF_BLOCKPLAYER) || ((rover->fofflags & FOF_BUSTUP) && (player->charflags & SF_CANBUSTWALLS)))
 									continue;
 
 								if (roverbelow == rover)
@@ -3256,8 +3256,8 @@ static void P_DoClimbing(player_t *player)
 
 					if (floorclimb)
 					{
-						if (rover->flags & FF_CRUMBLE && !(netgame && player->spectator))
-							EV_StartCrumble(rover->master->frontsector, rover, (rover->flags & FF_FLOATBOB), player, rover->alpha, !(rover->flags & FF_NORETURN));
+						if (rover->fofflags & FOF_CRUMBLE && !(netgame && player->spectator))
+							EV_StartCrumble(rover->master->frontsector, rover, (rover->fofflags & FOF_FLOATBOB), player, rover->alpha, !(rover->fofflags & FOF_NORETURN));
 						break;
 					}
 				}
@@ -3279,7 +3279,7 @@ static void P_DoClimbing(player_t *player)
 						ffloor_t *rover;
 						for (rover = glidesector->sector->ffloors; rover; rover = rover->next)
 						{
-							if (!(rover->flags & FF_EXISTS) || !(rover->flags & FF_BLOCKPLAYER) || ((rover->flags & FF_BUSTUP) && (player->charflags & SF_CANBUSTWALLS)))
+							if (!(rover->fofflags & FOF_EXISTS) || !(rover->fofflags & FOF_BLOCKPLAYER) || ((rover->fofflags & FOF_BUSTUP) && (player->charflags & SF_CANBUSTWALLS)))
 								continue;
 
 							bottomheight = P_GetFFloorBottomZAt(rover, player->mo->x, player->mo->y);
@@ -3319,7 +3319,7 @@ static void P_DoClimbing(player_t *player)
 						ffloor_t *rover;
 						for (rover = glidesector->sector->ffloors; rover; rover = rover->next)
 						{
-							if (!(rover->flags & FF_EXISTS) || !(rover->flags & FF_BLOCKPLAYER) || ((rover->flags & FF_BUSTUP) && (player->charflags & SF_CANBUSTWALLS)))
+							if (!(rover->fofflags & FOF_EXISTS) || !(rover->fofflags & FOF_BLOCKPLAYER) || ((rover->fofflags & FOF_BUSTUP) && (player->charflags & SF_CANBUSTWALLS)))
 								continue;
 
 							topheight = P_GetFFloorTopZAt(rover, player->mo->x, player->mo->y);
@@ -3693,14 +3693,14 @@ static void P_DoTeeter(player_t *player)
 
 			for (rover = sec->ffloors; rover; rover = rover->next)
 			{
-				if (!(rover->flags & FF_EXISTS)) continue;
+				if (!(rover->fofflags & FOF_EXISTS)) continue;
 
 				topheight    = P_GetFFloorTopZAt   (rover, player->mo->x, player->mo->y);
 				bottomheight = P_GetFFloorBottomZAt(rover, player->mo->x, player->mo->y);
 
 				if (P_CheckSolidLava(rover))
 					;
-				else if (!(rover->flags & FF_BLOCKPLAYER || rover->flags & FF_QUICKSAND))
+				else if (!(rover->fofflags & FOF_BLOCKPLAYER || rover->fofflags & FOF_QUICKSAND))
 					continue; // intangible 3d floor
 
 				if (player->mo->eflags & MFE_VERTICALFLIP)
@@ -10072,7 +10072,7 @@ boolean P_MoveChaseCamera(player_t *player, camera_t *thiscam, boolean resetcall
 			for (rover = newsubsec->sector->ffloors; rover; rover = rover->next)
 			{
 				fixed_t topheight, bottomheight;
-				if (!(rover->flags & FF_BLOCKOTHERS) || !(rover->flags & FF_EXISTS) || !(rover->flags & FF_RENDERALL) || (rover->master->frontsector->flags & MSF_NOCLIPCAMERA))
+				if (!(rover->fofflags & FOF_BLOCKOTHERS) || !(rover->fofflags & FOF_EXISTS) || !(rover->fofflags & FOF_RENDERALL) || (rover->master->frontsector->flags & MSF_NOCLIPCAMERA))
 					continue;
 
 				topheight = P_CameraGetFOFTopZ(thiscam, newsubsec->sector, rover, midx, midy, NULL);
@@ -10198,7 +10198,7 @@ boolean P_MoveChaseCamera(player_t *player, camera_t *thiscam, boolean resetcall
 			for (rover = newsubsec->sector->ffloors; rover; rover = rover->next)
 			{
 				fixed_t topheight, bottomheight;
-				if ((rover->flags & FF_BLOCKOTHERS) && (rover->flags & FF_RENDERALL) && (rover->flags & FF_EXISTS) && !(rover->master->frontsector->flags & MSF_NOCLIPCAMERA))
+				if ((rover->fofflags & FOF_BLOCKOTHERS) && (rover->fofflags & FOF_RENDERALL) && (rover->fofflags & FOF_EXISTS) && !(rover->master->frontsector->flags & MSF_NOCLIPCAMERA))
 				{
 					topheight = P_CameraGetFOFTopZ(thiscam, newsubsec->sector, rover, midx, midy, NULL);
 					bottomheight = P_CameraGetFOFBottomZ(thiscam, newsubsec->sector, rover, midx, midy, NULL);
@@ -10515,7 +10515,7 @@ static void P_CalcPostImg(player_t *player)
 
 		for (rover = sector->ffloors; rover; rover = rover->next)
 		{
-			if (!(rover->flags & FF_EXISTS))
+			if (!(rover->fofflags & FOF_EXISTS))
 				continue;
 
 			topheight    = P_GetFFloorTopZAt   (rover, player->mo->x, player->mo->y);
@@ -10541,7 +10541,7 @@ static void P_CalcPostImg(player_t *player)
 
 		for (rover = sector->ffloors; rover; rover = rover->next)
 		{
-			if (!(rover->flags & FF_EXISTS) || !(rover->flags & FF_SWIMMABLE) || rover->flags & FF_BLOCKPLAYER)
+			if (!(rover->fofflags & FOF_EXISTS) || !(rover->fofflags & FOF_SWIMMABLE) || rover->fofflags & FOF_BLOCKPLAYER)
 				continue;
 
 			topheight    = P_GetFFloorTopZAt   (rover, player->mo->x, player->mo->y);
@@ -10604,7 +10604,7 @@ static sector_t *P_GetMinecartSector(fixed_t x, fixed_t y, fixed_t z, fixed_t *n
 		ffloor_t *rover;
 		for (rover = sec->ffloors; rover; rover = rover->next)
 		{
-			if (!(rover->flags & (FF_EXISTS|FF_BLOCKOTHERS)))
+			if (!(rover->fofflags & (FOF_EXISTS|FOF_BLOCKOTHERS)))
 				continue;
 
 			*nz = P_GetFFloorTopZAt(rover, x, y);
@@ -12248,7 +12248,7 @@ static boolean P_MobjAboveLava(mobj_t *mobj)
 
 		for (rover = sector->ffloors; rover; rover = rover->next)
 		{
-			if (!(rover->flags & FF_EXISTS) || !(rover->flags & FF_SWIMMABLE))
+			if (!(rover->fofflags & FOF_EXISTS) || !(rover->fofflags & FOF_SWIMMABLE))
 				continue;
 
 			if (rover->master->frontsector->damagetype != SD_FIRE && rover->master->frontsector->damagetype != SD_LAVA)
diff --git a/src/r_bsp.c b/src/r_bsp.c
index f0a761d7b25244cedb6dcc0cd9ac7cce465a5d90..c9591b254469a2e512841c781aecb2d77c298118 100644
--- a/src/r_bsp.c
+++ b/src/r_bsp.c
@@ -919,7 +919,7 @@ static void R_Subsector(size_t num)
 
 		for (rover = frontsector->ffloors; rover && numffloors < MAXFFLOORS; rover = rover->next)
 		{
-			if (!(rover->flags & FF_EXISTS) || !(rover->flags & FF_RENDERPLANES))
+			if (!(rover->fofflags & FOF_EXISTS) || !(rover->fofflags & FOF_RENDERPLANES))
 				continue;
 
 			if (frontsector->cullheight)
@@ -939,8 +939,8 @@ static void R_Subsector(size_t num)
 			planecenterz = P_GetFFloorBottomZAt(rover, frontsector->soundorg.x, frontsector->soundorg.y);
 			if (planecenterz <= ceilingcenterz
 				&& planecenterz >= floorcenterz
-				&& ((viewz < heightcheck && (rover->flags & FF_BOTHPLANES || !(rover->flags & FF_INVERTPLANES)))
-				|| (viewz > heightcheck && (rover->flags & FF_BOTHPLANES || rover->flags & FF_INVERTPLANES))))
+				&& ((viewz < heightcheck && (rover->fofflags & FOF_BOTHPLANES || !(rover->fofflags & FOF_INVERTPLANES)))
+				|| (viewz > heightcheck && (rover->fofflags & FOF_BOTHPLANES || rover->fofflags & FOF_INVERTPLANES))))
 			{
 				light = R_GetPlaneLight(frontsector, planecenterz,
 					viewz < heightcheck);
@@ -969,8 +969,8 @@ static void R_Subsector(size_t num)
 			planecenterz = P_GetFFloorTopZAt(rover, frontsector->soundorg.x, frontsector->soundorg.y);
 			if (planecenterz >= floorcenterz
 				&& planecenterz <= ceilingcenterz
-				&& ((viewz > heightcheck && (rover->flags & FF_BOTHPLANES || !(rover->flags & FF_INVERTPLANES)))
-				|| (viewz < heightcheck && (rover->flags & FF_BOTHPLANES || rover->flags & FF_INVERTPLANES))))
+				&& ((viewz > heightcheck && (rover->fofflags & FOF_BOTHPLANES || !(rover->fofflags & FOF_INVERTPLANES)))
+				|| (viewz < heightcheck && (rover->fofflags & FOF_BOTHPLANES || rover->fofflags & FOF_INVERTPLANES))))
 			{
 				light = R_GetPlaneLight(frontsector, planecenterz, viewz < heightcheck);
 
@@ -1106,11 +1106,11 @@ void R_Prep3DFloors(sector_t *sector)
 	count = 1;
 	for (rover = sector->ffloors; rover; rover = rover->next)
 	{
-		if ((rover->flags & FF_EXISTS) && (!(rover->flags & FF_NOSHADE)
-			|| (rover->flags & FF_CUTLEVEL) || (rover->flags & FF_CUTSPRITES)))
+		if ((rover->fofflags & FOF_EXISTS) && (!(rover->fofflags & FOF_NOSHADE)
+			|| (rover->fofflags & FOF_CUTLEVEL) || (rover->fofflags & FOF_CUTSPRITES)))
 		{
 			count++;
-			if (rover->flags & FF_DOUBLESHADOW)
+			if (rover->fofflags & FOF_DOUBLESHADOW)
 				count++;
 		}
 	}
@@ -1141,8 +1141,8 @@ void R_Prep3DFloors(sector_t *sector)
 		for (rover = sector->ffloors; rover; rover = rover->next)
 		{
 			rover->lastlight = 0;
-			if (!(rover->flags & FF_EXISTS) || (rover->flags & FF_NOSHADE
-				&& !(rover->flags & FF_CUTLEVEL) && !(rover->flags & FF_CUTSPRITES)))
+			if (!(rover->fofflags & FOF_EXISTS) || (rover->fofflags & FOF_NOSHADE
+				&& !(rover->fofflags & FOF_CUTLEVEL) && !(rover->fofflags & FOF_CUTSPRITES)))
 			continue;
 
 			heighttest = P_GetFFloorTopZAt(rover, sector->soundorg.x, sector->soundorg.y);
@@ -1154,7 +1154,7 @@ void R_Prep3DFloors(sector_t *sector)
 				bestslope = *rover->t_slope;
 				continue;
 			}
-			if (rover->flags & FF_DOUBLESHADOW) {
+			if (rover->fofflags & FOF_DOUBLESHADOW) {
 				heighttest = P_GetFFloorBottomZAt(rover, sector->soundorg.x, sector->soundorg.y);
 
 				if (heighttest > bestheight
@@ -1175,16 +1175,16 @@ void R_Prep3DFloors(sector_t *sector)
 
 		sector->lightlist[i].height = maxheight = bestheight;
 		sector->lightlist[i].caster = best;
-		sector->lightlist[i].flags = best->flags;
+		sector->lightlist[i].flags = best->fofflags;
 		sector->lightlist[i].slope = bestslope;
 		sec = &sectors[best->secnum];
 
-		if (best->flags & FF_NOSHADE)
+		if (best->fofflags & FOF_NOSHADE)
 		{
 			sector->lightlist[i].lightlevel = sector->lightlist[i-1].lightlevel;
 			sector->lightlist[i].extra_colormap = sector->lightlist[i-1].extra_colormap;
 		}
-		else if (best->flags & FF_COLORMAPONLY)
+		else if (best->fofflags & FOF_COLORMAPONLY)
 		{
 			sector->lightlist[i].lightlevel = sector->lightlist[i-1].lightlevel;
 			sector->lightlist[i].extra_colormap = &sec->extra_colormap;
@@ -1195,7 +1195,7 @@ void R_Prep3DFloors(sector_t *sector)
 			sector->lightlist[i].extra_colormap = &sec->extra_colormap;
 		}
 
-		if (best->flags & FF_DOUBLESHADOW)
+		if (best->fofflags & FOF_DOUBLESHADOW)
 		{
 			heighttest = P_GetFFloorBottomZAt(best, sector->soundorg.x, sector->soundorg.y);
 			if (bestheight == heighttest) ///TODO: do this in a more efficient way -Red
diff --git a/src/r_defs.h b/src/r_defs.h
index 9788e6b58c6d0ebf726a94589dfdaf5540cf008f..6c9c91ab13125492652cc3ac3bb77bc4a5e671cc 100644
--- a/src/r_defs.h
+++ b/src/r_defs.h
@@ -115,43 +115,84 @@ typedef struct
   */
 typedef enum
 {
-	FF_EXISTS            = 0x1,        ///< Always set, to check for validity.
-	FF_BLOCKPLAYER       = 0x2,        ///< Solid to player, but nothing else
-	FF_BLOCKOTHERS       = 0x4,        ///< Solid to everything but player
-	FF_SOLID             = 0x6,        ///< Clips things.
-	FF_RENDERSIDES       = 0x8,        ///< Renders the sides.
-	FF_RENDERPLANES      = 0x10,       ///< Renders the floor/ceiling.
-	FF_RENDERALL         = 0x18,       ///< Renders everything.
-	FF_SWIMMABLE         = 0x20,       ///< Is a water block.
-	FF_NOSHADE           = 0x40,       ///< Messes with the lighting?
-	FF_CUTSOLIDS         = 0x80,       ///< Cuts out hidden solid pixels.
-	FF_CUTEXTRA          = 0x100,      ///< Cuts out hidden translucent pixels.
-	FF_CUTLEVEL          = 0x180,      ///< Cuts out all hidden pixels.
-	FF_CUTSPRITES        = 0x200,      ///< Final step in making 3D water.
-	FF_BOTHPLANES        = 0x400,      ///< Render inside and outside planes.
-	FF_EXTRA             = 0x800,      ///< Gets cut by ::FF_CUTEXTRA.
-	FF_TRANSLUCENT       = 0x1000,     ///< See through!
-	FF_FOG               = 0x2000,     ///< Fog "brush."
-	FF_INVERTPLANES      = 0x4000,     ///< Only render inside planes.
-	FF_ALLSIDES          = 0x8000,     ///< Render inside and outside sides.
-	FF_INVERTSIDES       = 0x10000,    ///< Only render inside sides.
-	FF_DOUBLESHADOW      = 0x20000,    ///< Make two lightlist entries to reset light?
-	FF_FLOATBOB          = 0x40000,    ///< Floats on water and bobs if you step on it.
-	FF_NORETURN          = 0x80000,    ///< Used with ::FF_CRUMBLE. Will not return to its original position after falling.
-	FF_CRUMBLE           = 0x100000,   ///< Falls 2 seconds after being stepped on, and randomly brings all touching crumbling 3dfloors down with it, providing their master sectors share the same tag (allows crumble platforms above or below, to also exist).
-	FF_GOOWATER          = 0x200000,   ///< Used with ::FF_SWIMMABLE. Makes thick bouncey goop.
-	FF_MARIO             = 0x400000,   ///< Acts like a question block when hit from underneath. Goodie spawned at top is determined by master sector.
-	FF_BUSTUP            = 0x800000,   ///< You can spin through/punch this block and it will crumble!
-	FF_QUICKSAND         = 0x1000000,  ///< Quicksand!
-	FF_PLATFORM          = 0x2000000,  ///< You can jump up through this to the top.
-	FF_REVERSEPLATFORM   = 0x4000000,  ///< A fall-through floor in normal gravity, a platform in reverse gravity.
-	FF_INTANGIBLEFLATS   = 0x6000000,  ///< Both flats are intangible, but the sides are still solid.
-	FF_RIPPLE            = 0x8000000,  ///< Ripple the flats
-	FF_COLORMAPONLY      = 0x10000000, ///< Only copy the colormap, not the lightlevel
-	FF_BOUNCY            = 0x20000000, ///< Bounces players
-	FF_SPLAT             = 0x40000000, ///< Use splat flat renderer (treat cyan pixels as invisible)
+	FOF_EXISTS            = 0x1,        ///< Always set, to check for validity.
+	FOF_BLOCKPLAYER       = 0x2,        ///< Solid to player, but nothing else
+	FOF_BLOCKOTHERS       = 0x4,        ///< Solid to everything but player
+	FOF_SOLID             = 0x6,        ///< Clips things.
+	FOF_RENDERSIDES       = 0x8,        ///< Renders the sides.
+	FOF_RENDERPLANES      = 0x10,       ///< Renders the floor/ceiling.
+	FOF_RENDERALL         = 0x18,       ///< Renders everything.
+	FOF_SWIMMABLE         = 0x20,       ///< Is a water block.
+	FOF_NOSHADE           = 0x40,       ///< Messes with the lighting?
+	FOF_CUTSOLIDS         = 0x80,       ///< Cuts out hidden solid pixels.
+	FOF_CUTEXTRA          = 0x100,      ///< Cuts out hidden translucent pixels.
+	FOF_CUTLEVEL          = 0x180,      ///< Cuts out all hidden pixels.
+	FOF_CUTSPRITES        = 0x200,      ///< Final step in making 3D water.
+	FOF_BOTHPLANES        = 0x400,      ///< Render inside and outside planes.
+	FOF_EXTRA             = 0x800,      ///< Gets cut by ::FOF_CUTEXTRA.
+	FOF_TRANSLUCENT       = 0x1000,     ///< See through!
+	FOF_FOG               = 0x2000,     ///< Fog "brush."
+	FOF_INVERTPLANES      = 0x4000,     ///< Only render inside planes.
+	FOF_ALLSIDES          = 0x8000,     ///< Render inside and outside sides.
+	FOF_INVERTSIDES       = 0x10000,    ///< Only render inside sides.
+	FOF_DOUBLESHADOW      = 0x20000,    ///< Make two lightlist entries to reset light?
+	FOF_FLOATBOB          = 0x40000,    ///< Floats on water and bobs if you step on it.
+	FOF_NORETURN          = 0x80000,    ///< Used with ::FOF_CRUMBLE. Will not return to its original position after falling.
+	FOF_CRUMBLE           = 0x100000,   ///< Falls 2 seconds after being stepped on, and randomly brings all touching crumbling 3dfloors down with it, providing their master sectors share the same tag (allows crumble platforms above or below, to also exist).
+	FOF_GOOWATER          = 0x200000,   ///< Used with ::FOF_SWIMMABLE. Makes thick bouncey goop.
+	FOF_MARIO             = 0x400000,   ///< Acts like a question block when hit from underneath. Goodie spawned at top is determined by master sector.
+	FOF_BUSTUP            = 0x800000,   ///< You can spin through/punch this block and it will crumble!
+	FOF_QUICKSAND         = 0x1000000,  ///< Quicksand!
+	FOF_PLATFORM          = 0x2000000,  ///< You can jump up through this to the top.
+	FOF_REVERSEPLATFORM   = 0x4000000,  ///< A fall-through floor in normal gravity, a platform in reverse gravity.
+	FOF_INTANGIBLEFLATS   = 0x6000000,  ///< Both flats are intangible, but the sides are still solid.
+	FOF_RIPPLE            = 0x8000000,  ///< Ripple the flats
+	FOF_COLORMAPONLY      = 0x10000000, ///< Only copy the colormap, not the lightlevel
+	FOF_BOUNCY            = 0x20000000, ///< Bounces players
+	FOF_SPLAT             = 0x40000000, ///< Use splat flat renderer (treat cyan pixels as invisible)
 } ffloortype_e;
 
+typedef enum
+{
+	FF_OLD_EXISTS            = 0x1,
+	FF_OLD_BLOCKPLAYER       = 0x2,
+	FF_OLD_BLOCKOTHERS       = 0x4,
+	FF_OLD_SOLID             = 0x6,
+	FF_OLD_RENDERSIDES       = 0x8,
+	FF_OLD_RENDERPLANES      = 0x10,
+	FF_OLD_RENDERALL         = 0x18,
+	FF_OLD_SWIMMABLE         = 0x20,
+	FF_OLD_NOSHADE           = 0x40,
+	FF_OLD_CUTSOLIDS         = 0x80,
+	FF_OLD_CUTEXTRA          = 0x100,
+	FF_OLD_CUTLEVEL          = 0x180,
+	FF_OLD_CUTSPRITES        = 0x200,
+	FF_OLD_BOTHPLANES        = 0x400,
+	FF_OLD_EXTRA             = 0x800,
+	FF_OLD_TRANSLUCENT       = 0x1000,
+	FF_OLD_FOG               = 0x2000,
+	FF_OLD_INVERTPLANES      = 0x4000,
+	FF_OLD_ALLSIDES          = 0x8000,
+	FF_OLD_INVERTSIDES       = 0x10000,
+	FF_OLD_DOUBLESHADOW      = 0x20000,
+	FF_OLD_FLOATBOB          = 0x40000,
+	FF_OLD_NORETURN          = 0x80000,
+	FF_OLD_CRUMBLE           = 0x100000,
+	FF_OLD_SHATTERBOTTOM     = 0x200000,
+	FF_OLD_GOOWATER          = 0x200000,
+	FF_OLD_MARIO             = 0x400000,
+	FF_OLD_BUSTUP            = 0x800000,
+	FF_OLD_QUICKSAND         = 0x1000000,
+	FF_OLD_PLATFORM          = 0x2000000,
+	FF_OLD_REVERSEPLATFORM   = 0x4000000,
+	FF_OLD_INTANGIBLEFLATS   = 0x6000000,
+	FF_OLD_SHATTER           = 0x8000000,
+	FF_OLD_SPINBUST          = 0x10000000,
+	FF_OLD_STRONGBUST        = 0x20000000,
+	FF_OLD_RIPPLE            = 0x40000000,
+	FF_OLD_COLORMAPONLY      = 0x80000000,
+} oldffloortype_e;
+
 typedef enum
 {
 	FB_PUSHABLES   = 0x1, // Bustable by pushables
@@ -187,7 +228,7 @@ typedef struct ffloor_s
 	struct pslope_s **b_slope;
 
 	size_t secnum;
-	ffloortype_e flags;
+	ffloortype_e fofflags;
 	struct line_s *master;
 
 	struct sector_s *target;
@@ -200,16 +241,16 @@ typedef struct ffloor_s
 	UINT8 blend; // blendmode
 	tic_t norender; // for culling
 
-	// Only relevant for FF_BUSTUP
+	// Only relevant for FOF_BUSTUP
 	ffloorbustflags_e bustflags;
 	UINT8 busttype;
 	INT16 busttag;
 
-	// Only relevant for FF_QUICKSAND
+	// Only relevant for FOF_QUICKSAND
 	fixed_t sinkspeed;
 	fixed_t friction;
 
-	// Only relevant for FF_BOUNCY
+	// Only relevant for FOF_BOUNCY
 	fixed_t bouncestrength;
 
 	// these are saved for netgames, so do not let Lua touch these!
@@ -230,7 +271,7 @@ typedef struct lightlist_s
 	extracolormap_t **extra_colormap; // pointer-to-a-pointer, so we can react to colormap changes
 	INT32 flags;
 	ffloor_t *caster;
-	struct pslope_s *slope; // FF_DOUBLESHADOW makes me have to store this pointer here. Bluh bluh.
+	struct pslope_s *slope; // FOF_DOUBLESHADOW makes me have to store this pointer here. Bluh bluh.
 } lightlist_t;
 
 
diff --git a/src/r_draw8.c b/src/r_draw8.c
index c9a9e957502ba09444fb9b9f3aca8f51540d1d01..4504ad1bdf5f47949c29dbaf72abb9be19d6d5ac 100644
--- a/src/r_draw8.c
+++ b/src/r_draw8.c
@@ -2128,7 +2128,7 @@ void R_DrawColumnShadowed_8(void)
 	{
 		// If the height of the light is above the column, get the colormap
 		// anyway because the lighting of the top should be affected.
-		solid = dc_lightlist[i].flags & FF_CUTSOLIDS;
+		solid = dc_lightlist[i].flags & FOF_CUTSOLIDS;
 
 		height = dc_lightlist[i].height >> LIGHTSCALESHIFT;
 		if (solid)
diff --git a/src/r_plane.c b/src/r_plane.c
index 7ea10f61676530486a798ed36920b10ca54f7f18..5f0ed9340ac4e60e8c2d13e0bec90be034357012 100644
--- a/src/r_plane.c
+++ b/src/r_plane.c
@@ -836,13 +836,13 @@ void R_DrawSinglePlane(visplane_t *pl)
 			// Don't draw planes that shouldn't be drawn.
 			for (rover = pl->ffloor->target->ffloors; rover; rover = rover->next)
 			{
-				if ((pl->ffloor->flags & FF_CUTEXTRA) && (rover->flags & FF_EXTRA))
+				if ((pl->ffloor->fofflags & FOF_CUTEXTRA) && (rover->fofflags & FOF_EXTRA))
 				{
-					if (pl->ffloor->flags & FF_EXTRA)
+					if (pl->ffloor->fofflags & FOF_EXTRA)
 					{
 						// The plane is from an extra 3D floor... Check the flags so
 						// there are no undesired cuts.
-						if (((pl->ffloor->flags & (FF_FOG|FF_SWIMMABLE)) == (rover->flags & (FF_FOG|FF_SWIMMABLE)))
+						if (((pl->ffloor->fofflags & (FOF_FOG|FOF_SWIMMABLE)) == (rover->fofflags & (FOF_FOG|FOF_SWIMMABLE)))
 							&& pl->height < *rover->topheight
 							&& pl->height > *rover->bottomheight)
 							return;
@@ -850,9 +850,9 @@ void R_DrawSinglePlane(visplane_t *pl)
 				}
 			}
 
-			if (pl->ffloor->flags & FF_TRANSLUCENT)
+			if (pl->ffloor->fofflags & FOF_TRANSLUCENT)
 			{
-				spanfunctype = (pl->ffloor->flags & FF_SPLAT) ? SPANDRAWFUNC_TRANSSPLAT : SPANDRAWFUNC_TRANS;
+				spanfunctype = (pl->ffloor->fofflags & FOF_SPLAT) ? SPANDRAWFUNC_TRANSSPLAT : SPANDRAWFUNC_TRANS;
 
 				// Hacked up support for alpha value in software mode Tails 09-24-2002
 				// ...unhacked by toaster 04-01-2021, re-hacked a little by sphere 19-11-2021
@@ -871,14 +871,14 @@ void R_DrawSinglePlane(visplane_t *pl)
 				else
 					light = LIGHTLEVELS-1;
 			}
-			else if (pl->ffloor->flags & FF_FOG)
+			else if (pl->ffloor->fofflags & FOF_FOG)
 			{
 				spanfunctype = SPANDRAWFUNC_FOG;
 				light = (pl->lightlevel >> LIGHTSEGSHIFT);
 			}
 			else light = (pl->lightlevel >> LIGHTSEGSHIFT);
 
-			if (pl->ffloor->flags & FF_RIPPLE)
+			if (pl->ffloor->fofflags & FOF_RIPPLE)
 			{
 				INT32 top, bottom;
 
diff --git a/src/r_segs.c b/src/r_segs.c
index c9f5f0d7bbb68c4ff451c8cc4b1a479692cdccf1..43a7f945fd37bdfde19ed0857a24f402270a7fda 100644
--- a/src/r_segs.c
+++ b/src/r_segs.c
@@ -244,7 +244,7 @@ void R_RenderMaskedSegRange(drawseg_t *ds, INT32 x1, INT32 x2)
 			rlight->flags = light->flags;
 
 			if ((colfunc != colfuncs[COLDRAWFUNC_FUZZY])
-				|| (rlight->flags & FF_FOG)
+				|| (rlight->flags & FOF_FOG)
 				|| (rlight->extra_colormap && (rlight->extra_colormap->flags & CMF_FOG)))
 				lightnum = (rlight->lightlevel >> LIGHTSEGSHIFT);
 			else
@@ -387,7 +387,7 @@ void R_RenderMaskedSegRange(drawseg_t *ds, INT32 x1, INT32 x2)
 					{
 						rlight = &dc_lightlist[i];
 
-						if ((rlight->flags & FF_NOSHADE))
+						if ((rlight->flags & FOF_NOSHADE))
 							continue;
 
 						if (rlight->lightnum < 0)
@@ -547,7 +547,7 @@ static boolean R_IsFFloorTranslucent(visffloor_t *pfloor)
 
 	// Polyobjects have no ffloors, and they're handled in the conditional above.
 	if (pfloor->ffloor != NULL)
-		return (pfloor->ffloor->flags & (FF_TRANSLUCENT|FF_FOG));
+		return (pfloor->ffloor->fofflags & (FOF_TRANSLUCENT|FOF_FOG));
 
 	return false;
 }
@@ -602,7 +602,7 @@ void R_RenderThickSideRange(drawseg_t *ds, INT32 x1, INT32 x2, ffloor_t *pfloor)
 		texnum = R_GetTextureNum(sides[newline->sidenum[0]].midtexture);
 	}
 
-	if (pfloor->flags & FF_TRANSLUCENT)
+	if (pfloor->fofflags & FOF_TRANSLUCENT)
 	{
 		boolean fuzzy = true;
 
@@ -621,7 +621,7 @@ void R_RenderThickSideRange(drawseg_t *ds, INT32 x1, INT32 x2, ffloor_t *pfloor)
 		if (fuzzy)
 			colfunc = colfuncs[COLDRAWFUNC_FUZZY];
 	}
-	else if (pfloor->flags & FF_FOG)
+	else if (pfloor->fofflags & FOF_FOG)
 		colfunc = colfuncs[COLDRAWFUNC_FOG];
 
 	range = max(ds->x2-ds->x1, 1);
@@ -684,7 +684,7 @@ void R_RenderThickSideRange(drawseg_t *ds, INT32 x1, INT32 x2, ffloor_t *pfloor)
 			else                                      rlight->heightstep = CLAMPMIN;
 			rlight->heightstep = (rlight->heightstep-rlight->height)/(range);
 			rlight->flags = light->flags;
-			if (light->flags & FF_CUTLEVEL)
+			if (light->flags & FOF_CUTLEVEL)
 			{
 				SLOPEPARAMS(*light->caster->b_slope, leftheight, rightheight, *light->caster->bottomheight)
 #undef SLOPEPARAMS
@@ -708,12 +708,12 @@ void R_RenderThickSideRange(drawseg_t *ds, INT32 x1, INT32 x2, ffloor_t *pfloor)
 			rlight->extra_colormap = *light->extra_colormap;
 
 			// Check if the current light effects the colormap/lightlevel
-			if (pfloor->flags & FF_FOG)
+			if (pfloor->fofflags & FOF_FOG)
 				rlight->lightnum = (pfloor->master->frontsector->lightlevel >> LIGHTSEGSHIFT);
 			else
 				rlight->lightnum = (rlight->lightlevel >> LIGHTSEGSHIFT);
 
-			if (pfloor->flags & FF_FOG || rlight->flags & FF_FOG || (rlight->extra_colormap && (rlight->extra_colormap->flags & CMF_FOG)))
+			if (pfloor->fofflags & FOF_FOG || rlight->flags & FOF_FOG || (rlight->extra_colormap && (rlight->extra_colormap->flags & CMF_FOG)))
 				;
 			else if (curline->v1->y == curline->v2->y)
 				rlight->lightnum--;
@@ -730,7 +730,7 @@ void R_RenderThickSideRange(drawseg_t *ds, INT32 x1, INT32 x2, ffloor_t *pfloor)
 		// Get correct light level!
 		if ((frontsector->extra_colormap && (frontsector->extra_colormap->flags & CMF_FOG)))
 			lightnum = (frontsector->lightlevel >> LIGHTSEGSHIFT);
-		else if (pfloor->flags & FF_FOG)
+		else if (pfloor->fofflags & FOF_FOG)
 			lightnum = (pfloor->master->frontsector->lightlevel >> LIGHTSEGSHIFT);
 		else if (colfunc == colfuncs[COLDRAWFUNC_FUZZY])
 			lightnum = LIGHTLEVELS-1;
@@ -738,7 +738,7 @@ void R_RenderThickSideRange(drawseg_t *ds, INT32 x1, INT32 x2, ffloor_t *pfloor)
 			lightnum = R_FakeFlat(frontsector, &tempsec, &templight, &templight, false)
 				->lightlevel >> LIGHTSEGSHIFT;
 
-		if (pfloor->flags & FF_FOG || (frontsector->extra_colormap && (frontsector->extra_colormap->flags & CMF_FOG)));
+		if (pfloor->fofflags & FOF_FOG || (frontsector->extra_colormap && (frontsector->extra_colormap->flags & CMF_FOG)));
 			else if (curline->v1->y == curline->v2->y)
 		lightnum--;
 		else if (curline->v1->x == curline->v2->x)
@@ -885,7 +885,7 @@ void R_RenderThickSideRange(drawseg_t *ds, INT32 x1, INT32 x2, ffloor_t *pfloor)
 					{
 						rlight = &dc_lightlist[i];
 						rlight->height += rlight->heightstep;
-						if (rlight->flags & FF_CUTLEVEL)
+						if (rlight->flags & FOF_CUTLEVEL)
 							rlight->botheight += rlight->botheightstep;
 					}
 				}
@@ -912,7 +912,7 @@ void R_RenderThickSideRange(drawseg_t *ds, INT32 x1, INT32 x2, ffloor_t *pfloor)
 				{
 					// Check if the current light effects the colormap/lightlevel
 					rlight = &dc_lightlist[i];
-					lighteffect = !(dc_lightlist[i].flags & FF_NOSHADE);
+					lighteffect = !(dc_lightlist[i].flags & FOF_NOSHADE);
 					if (lighteffect)
 					{
 						lightnum = rlight->lightnum;
@@ -929,7 +929,7 @@ void R_RenderThickSideRange(drawseg_t *ds, INT32 x1, INT32 x2, ffloor_t *pfloor)
 						if (pindex >= MAXLIGHTSCALE)
 							pindex = MAXLIGHTSCALE-1;
 
-						if (pfloor->flags & FF_FOG)
+						if (pfloor->fofflags & FOF_FOG)
 						{
 							if (pfloor->master->frontsector->extra_colormap)
 								rlight->rcolormap = pfloor->master->frontsector->extra_colormap->colormap + (xwalllights[pindex] - colormaps);
@@ -948,15 +948,15 @@ void R_RenderThickSideRange(drawseg_t *ds, INT32 x1, INT32 x2, ffloor_t *pfloor)
 					solid = 0; // don't carry over solid-cutting flag from the previous light
 
 					// Check if the current light can cut the current 3D floor.
-					if (rlight->flags & FF_CUTSOLIDS && !(pfloor->flags & FF_EXTRA))
+					if (rlight->flags & FOF_CUTSOLIDS && !(pfloor->fofflags & FOF_EXTRA))
 						solid = 1;
-					else if (rlight->flags & FF_CUTEXTRA && pfloor->flags & FF_EXTRA)
+					else if (rlight->flags & FOF_CUTEXTRA && pfloor->fofflags & FOF_EXTRA)
 					{
-						if (rlight->flags & FF_EXTRA)
+						if (rlight->flags & FOF_EXTRA)
 						{
 							// The light is from an extra 3D floor... Check the flags so
 							// there are no undesired cuts.
-							if ((rlight->flags & (FF_FOG|FF_SWIMMABLE)) == (pfloor->flags & (FF_FOG|FF_SWIMMABLE)))
+							if ((rlight->flags & (FOF_FOG|FOF_SWIMMABLE)) == (pfloor->fofflags & (FOF_FOG|FOF_SWIMMABLE)))
 								solid = 1;
 						}
 						else
@@ -993,7 +993,7 @@ void R_RenderThickSideRange(drawseg_t *ds, INT32 x1, INT32 x2, ffloor_t *pfloor)
 						{
 							rlight = &dc_lightlist[i];
 							rlight->height += rlight->heightstep;
-							if (rlight->flags & FF_CUTLEVEL)
+							if (rlight->flags & FOF_CUTLEVEL)
 								rlight->botheight += rlight->botheightstep;
 						}
 						continue;
@@ -1024,7 +1024,7 @@ void R_RenderThickSideRange(drawseg_t *ds, INT32 x1, INT32 x2, ffloor_t *pfloor)
 
 			dc_colormap = walllights[pindex];
 
-			if (pfloor->flags & FF_FOG && pfloor->master->frontsector->extra_colormap)
+			if (pfloor->fofflags & FOF_FOG && pfloor->master->frontsector->extra_colormap)
 				dc_colormap = pfloor->master->frontsector->extra_colormap->colormap + (dc_colormap - colormaps);
 			else if (frontsector->extra_colormap)
 				dc_colormap = frontsector->extra_colormap->colormap + (dc_colormap - colormaps);
@@ -1466,7 +1466,7 @@ static void R_RenderSegLoop (void)
 			for (i = 0; i < dc_numlights; i++)
 			{
 				dc_lightlist[i].height += dc_lightlist[i].heightstep;
-				if (dc_lightlist[i].flags & FF_CUTSOLIDS)
+				if (dc_lightlist[i].flags & FOF_CUTSOLIDS)
 					dc_lightlist[i].botheight += dc_lightlist[i].botheightstep;
 			}
 		}
@@ -2052,9 +2052,9 @@ void R_StoreWallRange(INT32 start, INT32 stop)
 				i = 0;
 				for (rover = backsector->ffloors; rover && i < MAXFFLOORS; rover = rover->next)
 				{
-					if (!(rover->flags & FF_RENDERSIDES) || !(rover->flags & FF_EXISTS))
+					if (!(rover->fofflags & FOF_RENDERSIDES) || !(rover->fofflags & FOF_EXISTS))
 						continue;
-					if (!(rover->flags & FF_ALLSIDES) && rover->flags & FF_INVERTSIDES)
+					if (!(rover->fofflags & FOF_ALLSIDES) && rover->fofflags & FOF_INVERTSIDES)
 						continue;
 
 					if (rover->norender == leveltime)
@@ -2071,23 +2071,23 @@ void R_StoreWallRange(INT32 start, INT32 stop)
 						if (r2->master == rover->master) // Skip if same control line.
 							break;
 
-						if (!(r2->flags & FF_EXISTS) || !(r2->flags & FF_RENDERSIDES))
+						if (!(r2->fofflags & FOF_EXISTS) || !(r2->fofflags & FOF_RENDERSIDES))
 							continue;
 
 						if (r2->norender == leveltime)
 							continue;
 
-						if (rover->flags & FF_EXTRA)
+						if (rover->fofflags & FOF_EXTRA)
 						{
-							if (!(r2->flags & FF_CUTEXTRA))
+							if (!(r2->fofflags & FOF_CUTEXTRA))
 								continue;
 
-							if (r2->flags & FF_EXTRA && (r2->flags & (FF_TRANSLUCENT|FF_FOG)) != (rover->flags & (FF_TRANSLUCENT|FF_FOG)))
+							if (r2->fofflags & FOF_EXTRA && (r2->fofflags & (FOF_TRANSLUCENT|FOF_FOG)) != (rover->fofflags & (FOF_TRANSLUCENT|FOF_FOG)))
 								continue;
 						}
 						else
 						{
-							if (!(r2->flags & FF_CUTSOLIDS))
+							if (!(r2->fofflags & FOF_CUTSOLIDS))
 								continue;
 						}
 
@@ -2110,9 +2110,9 @@ void R_StoreWallRange(INT32 start, INT32 stop)
 
 				for (rover = frontsector->ffloors; rover && i < MAXFFLOORS; rover = rover->next)
 				{
-					if (!(rover->flags & FF_RENDERSIDES) || !(rover->flags & FF_EXISTS))
+					if (!(rover->fofflags & FOF_RENDERSIDES) || !(rover->fofflags & FOF_EXISTS))
 						continue;
-					if (!(rover->flags & FF_ALLSIDES || rover->flags & FF_INVERTSIDES))
+					if (!(rover->fofflags & FOF_ALLSIDES || rover->fofflags & FOF_INVERTSIDES))
 						continue;
 
 					if (rover->norender == leveltime)
@@ -2129,23 +2129,23 @@ void R_StoreWallRange(INT32 start, INT32 stop)
 						if (r2->master == rover->master) // Skip if same control line.
 							break;
 
-						if (!(r2->flags & FF_EXISTS) || !(r2->flags & FF_RENDERSIDES))
+						if (!(r2->fofflags & FOF_EXISTS) || !(r2->fofflags & FOF_RENDERSIDES))
 							continue;
 
 						if (r2->norender == leveltime)
 							continue;
 
-						if (rover->flags & FF_EXTRA)
+						if (rover->fofflags & FOF_EXTRA)
 						{
-							if (!(r2->flags & FF_CUTEXTRA))
+							if (!(r2->fofflags & FOF_CUTEXTRA))
 								continue;
 
-							if (r2->flags & FF_EXTRA && (r2->flags & (FF_TRANSLUCENT|FF_FOG)) != (rover->flags & (FF_TRANSLUCENT|FF_FOG)))
+							if (r2->fofflags & FOF_EXTRA && (r2->fofflags & (FOF_TRANSLUCENT|FOF_FOG)) != (rover->fofflags & (FOF_TRANSLUCENT|FOF_FOG)))
 								continue;
 						}
 						else
 						{
-							if (!(r2->flags & FF_CUTSOLIDS))
+							if (!(r2->fofflags & FOF_CUTSOLIDS))
 								continue;
 						}
 
@@ -2170,9 +2170,9 @@ void R_StoreWallRange(INT32 start, INT32 stop)
 			{
 				for (rover = backsector->ffloors, i = 0; rover && i < MAXFFLOORS; rover = rover->next)
 				{
-					if (!(rover->flags & FF_RENDERSIDES) || !(rover->flags & FF_EXISTS))
+					if (!(rover->fofflags & FOF_RENDERSIDES) || !(rover->fofflags & FOF_EXISTS))
 						continue;
-					if (!(rover->flags & FF_ALLSIDES) && rover->flags & FF_INVERTSIDES)
+					if (!(rover->fofflags & FOF_ALLSIDES) && rover->fofflags & FOF_INVERTSIDES)
 						continue;
 					if (rover->norender == leveltime)
 						continue;
@@ -2192,9 +2192,9 @@ void R_StoreWallRange(INT32 start, INT32 stop)
 			{
 				for (rover = frontsector->ffloors, i = 0; rover && i < MAXFFLOORS; rover = rover->next)
 				{
-					if (!(rover->flags & FF_RENDERSIDES) || !(rover->flags & FF_EXISTS))
+					if (!(rover->fofflags & FOF_RENDERSIDES) || !(rover->fofflags & FOF_EXISTS))
 						continue;
-					if (!(rover->flags & FF_ALLSIDES || rover->flags & FF_INVERTSIDES))
+					if (!(rover->fofflags & FOF_ALLSIDES || rover->fofflags & FOF_INVERTSIDES))
 						continue;
 					if (rover->norender == leveltime)
 						continue;
@@ -2416,7 +2416,7 @@ void R_StoreWallRange(INT32 start, INT32 stop)
 			rlight->heightstep = (rlight->heightstep-rlight->height)/(range);
 			rlight->flags = light->flags;
 
-			if (light->caster && light->caster->flags & FF_CUTSOLIDS)
+			if (light->caster && light->caster->fofflags & FOF_CUTSOLIDS)
 			{
 				leftheight  = P_GetFFloorBottomZAt(light->caster,  segleft.x,  segleft.y);
 				rightheight = P_GetFFloorBottomZAt(light->caster, segright.x, segright.y);
@@ -2503,7 +2503,7 @@ void R_StoreWallRange(INT32 start, INT32 stop)
 			{
 				for (rover = backsector->ffloors; rover && i < MAXFFLOORS; rover = rover->next)
 				{
-					if (!(rover->flags & FF_EXISTS) || !(rover->flags & FF_RENDERPLANES))
+					if (!(rover->fofflags & FOF_EXISTS) || !(rover->fofflags & FOF_RENDERPLANES))
 						continue;
 					if (rover->norender == leveltime)
 						continue;
@@ -2518,8 +2518,8 @@ void R_StoreWallRange(INT32 start, INT32 stop)
 
 					if ((roverleft>>4 <= worldhigh || roverright>>4 <= worldhighslope) &&
 					    (roverleft>>4 >= worldlow || roverright>>4 >= worldlowslope) &&
-					    ((viewz < planevistest && (rover->flags & FF_BOTHPLANES || !(rover->flags & FF_INVERTPLANES))) ||
-					     (viewz > planevistest && (rover->flags & FF_BOTHPLANES || rover->flags & FF_INVERTPLANES))))
+					    ((viewz < planevistest && (rover->fofflags & FOF_BOTHPLANES || !(rover->fofflags & FOF_INVERTPLANES))) ||
+					     (viewz > planevistest && (rover->fofflags & FOF_BOTHPLANES || rover->fofflags & FOF_INVERTPLANES))))
 					{
 						//ffloor[i].slope = *rover->b_slope;
 						ffloor[i].b_pos = roverleft;
@@ -2541,8 +2541,8 @@ void R_StoreWallRange(INT32 start, INT32 stop)
 
 					if ((roverleft>>4 <= worldhigh || roverright>>4 <= worldhighslope) &&
 					    (roverleft>>4 >= worldlow || roverright>>4 >= worldlowslope) &&
-					    ((viewz > planevistest && (rover->flags & FF_BOTHPLANES || !(rover->flags & FF_INVERTPLANES))) ||
-					     (viewz < planevistest && (rover->flags & FF_BOTHPLANES || rover->flags & FF_INVERTPLANES))))
+					    ((viewz > planevistest && (rover->fofflags & FOF_BOTHPLANES || !(rover->fofflags & FOF_INVERTPLANES))) ||
+					     (viewz < planevistest && (rover->fofflags & FOF_BOTHPLANES || rover->fofflags & FOF_INVERTPLANES))))
 					{
 						//ffloor[i].slope = *rover->t_slope;
 						ffloor[i].b_pos = roverleft;
@@ -2560,7 +2560,7 @@ void R_StoreWallRange(INT32 start, INT32 stop)
 			{
 				for (rover = frontsector->ffloors; rover && i < MAXFFLOORS; rover = rover->next)
 				{
-					if (!(rover->flags & FF_EXISTS) || !(rover->flags & FF_RENDERPLANES))
+					if (!(rover->fofflags & FOF_EXISTS) || !(rover->fofflags & FOF_RENDERPLANES))
 						continue;
 					if (rover->norender == leveltime)
 						continue;
@@ -2575,8 +2575,8 @@ void R_StoreWallRange(INT32 start, INT32 stop)
 
 					if ((roverleft>>4 <= worldhigh || roverright>>4 <= worldhighslope) &&
 					    (roverleft>>4 >= worldlow || roverright>>4 >= worldlowslope) &&
-					    ((viewz < planevistest && (rover->flags & FF_BOTHPLANES || !(rover->flags & FF_INVERTPLANES))) ||
-					     (viewz > planevistest && (rover->flags & FF_BOTHPLANES || rover->flags & FF_INVERTPLANES))))
+					    ((viewz < planevistest && (rover->fofflags & FOF_BOTHPLANES || !(rover->fofflags & FOF_INVERTPLANES))) ||
+					     (viewz > planevistest && (rover->fofflags & FOF_BOTHPLANES || rover->fofflags & FOF_INVERTPLANES))))
 					{
 						//ffloor[i].slope = *rover->b_slope;
 						ffloor[i].b_pos = roverleft;
@@ -2598,8 +2598,8 @@ void R_StoreWallRange(INT32 start, INT32 stop)
 
 					if ((roverleft>>4 <= worldhigh || roverright>>4 <= worldhighslope) &&
 					    (roverleft>>4 >= worldlow || roverright>>4 >= worldlowslope) &&
-					    ((viewz > planevistest && (rover->flags & FF_BOTHPLANES || !(rover->flags & FF_INVERTPLANES))) ||
-					     (viewz < planevistest && (rover->flags & FF_BOTHPLANES || rover->flags & FF_INVERTPLANES))))
+					    ((viewz > planevistest && (rover->fofflags & FOF_BOTHPLANES || !(rover->fofflags & FOF_INVERTPLANES))) ||
+					     (viewz < planevistest && (rover->fofflags & FOF_BOTHPLANES || rover->fofflags & FOF_INVERTPLANES))))
 					{
 						//ffloor[i].slope = *rover->t_slope;
 						ffloor[i].b_pos = roverleft;
diff --git a/src/r_things.c b/src/r_things.c
index 343a80f9555d0322fbe429836e885eb83e4c68fc..e689e284a96b1e90a9bc68b5d0260f4061990516 100644
--- a/src/r_things.c
+++ b/src/r_things.c
@@ -1055,7 +1055,7 @@ static void R_SplitSprite(vissprite_t *sprite)
 	{
 		fixed_t testheight;
 
-		if (!(sector->lightlist[i].caster->flags & FF_CUTSPRITES))
+		if (!(sector->lightlist[i].caster->fofflags & FOF_CUTSPRITES))
 			continue;
 
 		testheight = P_GetLightZAt(&sector->lightlist[i], sprite->gx, sprite->gy);
@@ -1096,7 +1096,7 @@ static void R_SplitSprite(vissprite_t *sprite)
 		newsprite->szt -= 8;
 
 		newsprite->cut |= SC_TOP;
-		if (!(sector->lightlist[i].caster->flags & FF_NOSHADE))
+		if (!(sector->lightlist[i].caster->fofflags & FOF_NOSHADE))
 		{
 			lightnum = (*sector->lightlist[i].lightlevel >> LIGHTSEGSHIFT);
 
@@ -1162,7 +1162,7 @@ fixed_t R_GetShadowZ(mobj_t *thing, pslope_t **shadowslope)
 		if (sector->ffloors)
 			for (rover = sector->ffloors; rover; rover = rover->next)
 			{
-				if (!(rover->flags & FF_EXISTS) || !(rover->flags & FF_RENDERPLANES) || (rover->alpha < 90 && !(rover->flags & FF_SWIMMABLE)))
+				if (!(rover->fofflags & FOF_EXISTS) || !(rover->fofflags & FOF_RENDERPLANES) || (rover->alpha < 90 && !(rover->fofflags & FOF_SWIMMABLE)))
 					continue;
 
 				z = isflipped ? P_GetFFloorBottomZAt(rover, thing->x, thing->y) : P_GetFFloorTopZAt(rover, thing->x, thing->y);