diff --git a/src/actor.h b/src/actor.h
index 862858b32..402253a7b 100644
--- a/src/actor.h
+++ b/src/actor.h
@@ -39,6 +39,7 @@
 #include "s_sound.h"
 #include "memarena.h"
 #include "g_level.h"
+#include "tflags.h"
 
 struct subsector_t;
 //
@@ -105,10 +106,9 @@ struct subsector_t;
 // Any questions?
 //
 
-enum
-{
 // --- mobj.flags ---
-
+enum ActorFlag
+{
 	MF_SPECIAL			= 0x00000001,	// call P_SpecialThing when touched
 	MF_SOLID			= 0x00000002,
 	MF_SHOOTABLE		= 0x00000004,
@@ -152,8 +152,13 @@ enum
 	MF_STEALTH			= 0x40000000,	// [RH] Andy Baker's stealth monsters
 	MF_ICECORPSE		= 0x80000000,	// a frozen corpse (for blasting) [RH] was 0x800000
 
-// --- mobj.flags2 ---
+	// --- dummies for unknown/unimplemented Strife flags ---
+	MF_STRIFEx8000000 = 0,		// seems related to MF_SHADOW
+};
 
+// --- mobj.flags2 ---
+enum ActorFlag2
+{
 	MF2_DONTREFLECT		= 0x00000001,	// this projectile cannot be reflected
 	MF2_WINDTHRUST		= 0x00000002,	// gets pushed around by the wind specials
 	MF2_DONTSEEKINVISIBLE=0x00000004,	// For seeker missiles: Don't home in on invisible/shadow targets
@@ -191,9 +196,11 @@ enum
 										// args should not be taken from the mapthing definition
 	MF2_SEEKERMISSILE	= 0x40000000,	// is a seeker (for reflection)
 	MF2_REFLECTIVE		= 0x80000000,	// reflects missiles
+};
 
 // --- mobj.flags3 ---
-
+enum ActorFlag3
+{
 	MF3_FLOORHUGGER		= 0x00000001,	// Missile stays on floor
 	MF3_CEILINGHUGGER	= 0x00000002,	// Missile stays on ceiling
 	MF3_NORADIUSDMG		= 0x00000004,	// Actor does not take radius damage
@@ -226,9 +233,11 @@ enum
 	MF3_WARNBOT			= 0x20000000,	// Missile warns bot
 	MF3_PUFFONACTORS	= 0x40000000,	// Puff appears even when hit bleeding actors
 	MF3_HUNTPLAYERS		= 0x80000000,	// Used with TIDtoHate, means to hate players too
+};
 
 // --- mobj.flags4 ---
-
+enum ActorFlag4
+{
 	MF4_NOHATEPLAYERS	= 0x00000001,	// Ignore player attacks
 	MF4_QUICKTORETALIATE= 0x00000002,	// Always switch targets when hurt
 	MF4_NOICEDEATH		= 0x00000004,	// Actor never enters an ice death, not even the generic one
@@ -262,9 +271,12 @@ enum
 	MF4_EXTREMEDEATH	= 0x20000000,	// this projectile or weapon always gibs its victim
 	MF4_FRIGHTENED		= 0x40000000,	// Monster runs away from player
 	MF4_BOSSSPAWNED		= 0x80000000,	// Spawned by a boss spawn cube
-	
+};
+
 // --- mobj.flags5 ---
 
+enum ActorFlag5
+{
 	MF5_DONTDRAIN		= 0x00000001,	// cannot be drained health from.
 	/*					= 0x00000002,	   reserved for use by scripting branch */
 	MF5_NODROPOFF		= 0x00000004,	// cannot drop off under any circumstances.
@@ -298,9 +310,11 @@ enum
 	MF5_INCONVERSATION	= 0x20000000,	// Actor is having a conversation
 	MF5_PAINLESS		= 0x40000000,	// Actor always inflicts painless damage.
 	MF5_MOVEWITHSECTOR	= 0x80000000,	// P_ChangeSector() will still process this actor if it has MF_NOBLOCKMAP
+};
 
 // --- mobj.flags6 ---
-
+enum ActorFlag6
+{
 	MF6_NOBOSSRIP		= 0x00000001,	// For rippermissiles: Don't rip through bosses.
 	MF6_THRUSPECIES		= 0x00000002,	// Actors passes through other of the same species.
 	MF6_MTHRUSPECIES	= 0x00000004,	// Missile passes through actors of its shooter's species.
@@ -333,9 +347,11 @@ enum
 	MF6_NOTAUTOAIMED	= 0x20000000,	// Do not subject actor to player autoaim.
 	MF6_NOTONAUTOMAP	= 0x40000000,	// will not be shown on automap with the 'scanner' powerup.
 	MF6_RELATIVETOFLOOR	= 0x80000000,	// [RC] Make flying actors be affected by lifts.
+};
 
 // --- mobj.flags7 ---
-
+enum ActorFlag7
+{
 	MF7_NEVERTARGET		= 0x00000001,	// can not be targetted at all, even if monster friendliness is considered.
 	MF7_NOTELESTOMP		= 0x00000002,	// cannot telefrag under any circumstances (even when set by MAPINFO)
 	MF7_ALWAYSTELEFRAG	= 0x00000004,	// will unconditionally be telefragged when in the way. Overrides all other settings.
@@ -354,11 +370,11 @@ enum
 	MF7_HITMASTER		= 0x00008000,	// Same as HITTARGET, except it's master instead of target.
 	MF7_HITTRACER		= 0x00010000,	// Same as HITTARGET, but for tracer.
 	MF7_FLYCHEAT		= 0x00020000,	// must be part of the actor so that it can be tracked properly
-
-
+};
 
 // --- mobj.renderflags ---
-
+enum ActorRenderFlag
+{
 	RF_XFLIP			= 0x0001,	// Flip sprite horizontally
 	RF_YFLIP			= 0x0002,	// Flip sprite vertically
 	RF_ONESIDED			= 0x0004,	// Wall/floor sprite is visible from front only
@@ -387,10 +403,6 @@ enum
 
 	RF_FORCEYBILLBOARD		= 0x10000,	// [BB] OpenGL only: draw with y axis billboard, i.e. anchored to the floor (overrides gl_billboard_mode setting)
 	RF_FORCEXYBILLBOARD		= 0x20000,	// [BB] OpenGL only: draw with xy axis billboard, i.e. unanchored (overrides gl_billboard_mode setting)
-
-// --- dummies for unknown/unimplemented Strife flags ---
-
-	MF_STRIFEx8000000 = 0,		// seems related to MF_SHADOW
 };
 
 #define TRANSLUC25			(FRACUNIT/4)
@@ -419,7 +431,7 @@ enum replace_t
 	ALLOW_REPLACE = 1
 };
 
-enum EBounceFlags
+enum ActorBounceFlag
 {
 	BOUNCE_Walls = 1<<0,		// bounces off of walls
 	BOUNCE_Floors = 1<<1,		// bounces off of floors
@@ -473,6 +485,26 @@ enum EBounceFlags
 
 };
 
+// [TP] Flagset definitions
+typedef TFlags<ActorFlag> ActorFlags;
+typedef TFlags<ActorFlag2> ActorFlags2;
+typedef TFlags<ActorFlag3> ActorFlags3;
+typedef TFlags<ActorFlag4> ActorFlags4;
+typedef TFlags<ActorFlag5> ActorFlags5;
+typedef TFlags<ActorFlag6> ActorFlags6;
+typedef TFlags<ActorFlag7> ActorFlags7;
+typedef TFlags<ActorRenderFlag> ActorRenderFlags;
+typedef TFlags<ActorBounceFlag, WORD> ActorBounceFlags;
+DEFINE_TFLAGS_OPERATORS (ActorFlags)
+DEFINE_TFLAGS_OPERATORS (ActorFlags2)
+DEFINE_TFLAGS_OPERATORS (ActorFlags3)
+DEFINE_TFLAGS_OPERATORS (ActorFlags4)
+DEFINE_TFLAGS_OPERATORS (ActorFlags5)
+DEFINE_TFLAGS_OPERATORS (ActorFlags6)
+DEFINE_TFLAGS_OPERATORS (ActorFlags7)
+DEFINE_TFLAGS_OPERATORS (ActorRenderFlags)
+DEFINE_TFLAGS_OPERATORS (ActorBounceFlags)
+
 // Used to affect the logic for thing activation through death, USESPECIAL and BUMPSPECIAL
 // "thing" refers to what has the flag and the special, "trigger" refers to what used or bumped it
 enum EThingSpecialActivationType
@@ -838,7 +870,7 @@ public:
 	BYTE			frame;				// sprite frame to draw
 	fixed_t			scaleX, scaleY;		// Scaling values; FRACUNIT is normal size
 	FRenderStyle	RenderStyle;		// Style to draw this actor with
-	DWORD			renderflags;		// Different rendering flags
+	ActorRenderFlags	renderflags;		// Different rendering flags
 	FTextureID		picnum;				// Draw this instead of sprite if valid
 	DWORD			effects;			// [RH] see p_effect.h
 	fixed_t			alpha;
@@ -864,13 +896,13 @@ public:
 	FState			*state;
 	SDWORD			Damage;			// For missiles and monster railgun
 	int				projectileKickback;
-	DWORD			flags;
-	DWORD			flags2;			// Heretic flags
-	DWORD			flags3;			// [RH] Hexen/Heretic actor-dependant behavior made flaggable
-	DWORD			flags4;			// [RH] Even more flags!
-	DWORD			flags5;			// OMG! We need another one.
-	DWORD			flags6;			// Shit! Where did all the flags go?
-	DWORD			flags7;			// WHO WANTS TO BET ON 8!?
+	ActorFlags		flags;
+	ActorFlags2		flags2;			// Heretic flags
+	ActorFlags3		flags3;			// [RH] Hexen/Heretic actor-dependant behavior made flaggable
+	ActorFlags4		flags4;			// [RH] Even more flags!
+	ActorFlags5		flags5;			// OMG! We need another one.
+	ActorFlags6		flags6;			// Shit! Where did all the flags go?
+	ActorFlags7		flags7;			// WHO WANTS TO BET ON 8!?
 
 	// [BB] If 0, everybody can see the actor, if > 0, only members of team (VisibleToTeam-1) can see it.
 	DWORD			VisibleToTeam;
@@ -916,7 +948,7 @@ public:
 	BYTE			boomwaterlevel;	// splash information for non-swimmable water sectors
 	BYTE			MinMissileChance;// [RH] If a random # is > than this, then missile attack.
 	SBYTE			LastLookPlayerNumber;// Player number last looked for (if TIDtoHate == 0)
-	WORD			BounceFlags;	// which bouncing type?
+	ActorBounceFlags	BounceFlags;	// which bouncing type?
 	DWORD			SpawnFlags;		// Increased to DWORD because of Doom 64
 	fixed_t			meleerange;		// specifies how far a melee attack reaches.
 	fixed_t			meleethreshold;	// Distance below which a monster doesn't try to shoot missiles anynore
diff --git a/src/b_func.cpp b/src/b_func.cpp
index 2800c01c5..f93625612 100644
--- a/src/b_func.cpp
+++ b/src/b_func.cpp
@@ -544,7 +544,7 @@ angle_t DBot::FireRox (AActor *enemy, ticcmd_t *cmd)
 // creating side-effects during gameplay.
 bool FCajunMaster::SafeCheckPosition (AActor *actor, fixed_t x, fixed_t y, FCheckPosition &tm)
 {
-	int savedFlags = actor->flags;
+	ActorFlags savedFlags = actor->flags;
 	actor->flags &= ~MF_PICKUP;
 	bool res = P_CheckPosition (actor, x, y, tm);
 	actor->flags = savedFlags;
diff --git a/src/d_dehacked.cpp b/src/d_dehacked.cpp
index 4a436c0a8..7d3a5f0ee 100644
--- a/src/d_dehacked.cpp
+++ b/src/d_dehacked.cpp
@@ -1135,31 +1135,31 @@ static int PatchThing (int thingy)
 						// triggering line effects and can teleport when the missile flag is removed.
 						info->flags2 &= ~MF2_NOTELEPORT;
 					}
-					info->flags = value[0];
+					info->flags = ActorFlags::FromInt (value[0]);
 				}
 				if (vchanged[1])
 				{
-					info->flags2 = value[1];
+					info->flags2 = ActorFlags2::FromInt (value[1]);
 					if (info->flags2 & 0x00000004)	// old BOUNCE1
 					{ 	
-						info->flags2 &= ~4;
+						info->flags2 &= ActorFlags2::FromInt (~4);
 						info->BounceFlags = BOUNCE_DoomCompat;
 					}
 					// Damage types that once were flags but now are not
 					if (info->flags2 & 0x20000000)
 					{
 						info->DamageType = NAME_Ice;
-						info->flags2 &= ~0x20000000;
+						info->flags2 &= ActorFlags2::FromInt (~0x20000000);
 					}
 					if (info->flags2 & 0x10000)
 					{
 						info->DamageType = NAME_Fire;
-						info->flags2 &= ~0x10000;
+						info->flags2 &= ActorFlags2::FromInt (~0x10000);
 					}
 					if (info->flags2 & 1)
 					{
 						info->gravity = FRACUNIT/4;
-						info->flags2 &= ~1;
+						info->flags2 &= ActorFlags2::FromInt (~1);
 					}
 				}
 				if (vchanged[2])
diff --git a/src/farchive.h b/src/farchive.h
index 329b448db..87ebf999b 100644
--- a/src/farchive.h
+++ b/src/farchive.h
@@ -37,6 +37,7 @@
 #include <stdio.h>
 #include "dobject.h"
 #include "r_state.h"
+#include "tflags.h"
 
 class FFile
 {
@@ -333,4 +334,10 @@ FArchive &operator<< (FArchive &arc, side_t *&side);
 
 
 
+template<typename T, typename TT>
+FArchive& operator<< (FArchive& arc, TFlags<T, TT>& flag)
+{
+	return flag.Serialize (arc);
+}
+
 #endif //__FARCHIVE_H__
diff --git a/src/fragglescript/t_func.cpp b/src/fragglescript/t_func.cpp
index 0bddcd7fd..165c51c66 100644
--- a/src/fragglescript/t_func.cpp
+++ b/src/fragglescript/t_func.cpp
@@ -1216,11 +1216,14 @@ void FParser::SF_ObjFlag(void)
 			
 			if(mo && flagnum<26)          // nullptr check
 			{
+				DWORD tempflags = mo->flags;
+
 				// remove old bit
-				mo->flags &= ~(1 << flagnum);
+				tempflags &= ~(1 << flagnum);
 				
 				// make the new flag
-				mo->flags |= (!!intvalue(t_argv[2])) << flagnum;
+				tempflags |= (!!intvalue(t_argv[2])) << flagnum;
+				mo->flags = ActorFlags::FromInt (tempflags);
 			}  
 		}
 		t_return.type = svt_int;  
diff --git a/src/g_shared/a_morph.cpp b/src/g_shared/a_morph.cpp
index e3433f12e..0d3513e37 100644
--- a/src/g_shared/a_morph.cpp
+++ b/src/g_shared/a_morph.cpp
@@ -228,7 +228,7 @@ bool P_UndoPlayerMorph (player_t *activator, player_t *player, int unmorphflag,
 	mo->angle = pmo->angle;
 	mo->player = player;
 	mo->reactiontime = 18;
-	mo->flags = pmo->special2 & ~MF_JUSTHIT;
+	mo->flags = ActorFlags::FromInt (pmo->special2) & ~MF_JUSTHIT;
 	mo->velx = 0;
 	mo->vely = 0;
 	player->velx = 0;
@@ -438,7 +438,7 @@ bool P_UndoMonsterMorph (AMorphedMonster *beast, bool force)
 	actor->SetOrigin (beast->x, beast->y, beast->z);
 	actor->flags |= MF_SOLID;
 	beast->flags &= ~MF_SOLID;
-	int beastflags6 = beast->flags6;
+	ActorFlags6 beastflags6 = beast->flags6;
 	beast->flags6 &= ~MF6_TOUCHY;
 	if (!force && !P_TestMobjLocation (actor))
 	{ // Didn't fit
diff --git a/src/g_shared/a_movingcamera.cpp b/src/g_shared/a_movingcamera.cpp
index 83d0d4695..0f847fa41 100644
--- a/src/g_shared/a_movingcamera.cpp
+++ b/src/g_shared/a_movingcamera.cpp
@@ -603,9 +603,9 @@ void AActorMover::Deactivate (AActor *activator)
 		if (tracer != NULL)
 		{
 			tracer->UnlinkFromWorld ();
-			tracer->flags = special1;
+			tracer->flags = ActorFlags::FromInt (special1);
 			tracer->LinkToWorld ();
-			tracer->flags2 = special2;
+			tracer->flags2 = ActorFlags2::FromInt (special2);
 		}
 	}
 }
diff --git a/src/g_shared/a_sharedglobal.h b/src/g_shared/a_sharedglobal.h
index 3d9e4ed10..2688249ea 100644
--- a/src/g_shared/a_sharedglobal.h
+++ b/src/g_shared/a_sharedglobal.h
@@ -202,7 +202,7 @@ public:
 	TObjPtr<AActor> UnmorphedMe;
 	int UnmorphTime, MorphStyle;
 	const PClass *MorphExitFlash;
-	DWORD FlagsSave;
+	ActorFlags FlagsSave;
 };
 
 class AMapMarker : public AActor
diff --git a/src/p_acs.cpp b/src/p_acs.cpp
index 5556507b7..44c156bc5 100644
--- a/src/p_acs.cpp
+++ b/src/p_acs.cpp
@@ -3381,7 +3381,7 @@ int DLevelScript::DoSpawn (int type, fixed_t x, fixed_t y, fixed_t z, int tid, i
 		actor = Spawn (info, x, y, z, ALLOW_REPLACE);
 		if (actor != NULL)
 		{
-			DWORD oldFlags2 = actor->flags2;
+			ActorFlags2 oldFlags2 = actor->flags2;
 			actor->flags2 |= MF2_PASSMOBJ;
 			if (force || P_TestMobjLocation (actor))
 			{
diff --git a/src/p_buildmap.cpp b/src/p_buildmap.cpp
index ddfa0e2ec..46c2b9f4c 100644
--- a/src/p_buildmap.cpp
+++ b/src/p_buildmap.cpp
@@ -894,5 +894,5 @@ void ACustomSprite::BeginPlay ()
 	if (cstat & 8)
 		renderflags |= RF_YFLIP;
 	// set face/wall/floor flags
-	renderflags |= ((cstat >> 4) & 3) << 12;
+	renderflags |= ActorRenderFlags::FromInt (((cstat >> 4) & 3) << 12);
 }
diff --git a/src/p_enemy.cpp b/src/p_enemy.cpp
index 540aa119e..3e17a85f3 100644
--- a/src/p_enemy.cpp
+++ b/src/p_enemy.cpp
@@ -2573,7 +2573,7 @@ static bool P_CheckForResurrection(AActor *self, bool usevilestates)
 
 				fixed_t oldheight = corpsehit->height;
 				fixed_t oldradius = corpsehit->radius;
-				int oldflags = corpsehit->flags;
+				ActorFlags oldflags = corpsehit->flags;
 
 				corpsehit->flags |= MF_SOLID;
 				corpsehit->height = corpsehit->GetDefault()->height;
diff --git a/src/p_map.cpp b/src/p_map.cpp
index 1ad1728ce..b16ddb179 100644
--- a/src/p_map.cpp
+++ b/src/p_map.cpp
@@ -1590,7 +1590,7 @@ bool P_CheckPosition(AActor *thing, fixed_t x, fixed_t y, bool actorsonly)
 
 bool P_TestMobjLocation(AActor *mobj)
 {
-	int flags;
+	ActorFlags flags;
 
 	flags = mobj->flags;
 	mobj->flags &= ~MF_PICKUP;
@@ -4916,7 +4916,7 @@ EXTERN_CVAR(Int, cl_bloodtype)
 
 bool P_AdjustFloorCeil(AActor *thing, FChangePosition *cpos)
 {
-	int flags2 = thing->flags2 & MF2_PASSMOBJ;
+	ActorFlags2 flags2 = thing->flags2 & MF2_PASSMOBJ;
 	FCheckPosition tm;
 
 	if ((thing->flags2 & MF2_PASSMOBJ) && (thing->flags3 & MF3_ISMONSTER))
diff --git a/src/p_mobj.cpp b/src/p_mobj.cpp
index 2571413c8..7cc0fd497 100644
--- a/src/p_mobj.cpp
+++ b/src/p_mobj.cpp
@@ -481,7 +481,7 @@ bool AActor::SetState (FState *newstate, bool nofunction)
 		}
 		state = newstate;
 		tics = GetTics(newstate);
-		renderflags = (renderflags & ~RF_FULLBRIGHT) | newstate->GetFullbright();
+		renderflags = (renderflags & ~RF_FULLBRIGHT) | ActorRenderFlags::FromInt (newstate->GetFullbright());
 		newsprite = newstate->sprite;
 		if (newsprite != SPR_FIXED)
 		{ // okay to change sprite and/or frame
@@ -3940,7 +3940,7 @@ AActor *AActor::StaticSpawn (const PClass *type, fixed_t ix, fixed_t iy, fixed_t
 	
 	actor->sprite = st->sprite;
 	actor->frame = st->GetFrame();
-	actor->renderflags = (actor->renderflags & ~RF_FULLBRIGHT) | st->GetFullbright();
+	actor->renderflags = (actor->renderflags & ~RF_FULLBRIGHT) | ActorRenderFlags::FromInt (st->GetFullbright());
 	actor->touching_sectorlist = NULL;	// NULL head of sector list // phares 3/13/98
 	if (G_SkillProperty(SKILLP_FastMonsters))
 		actor->Speed = actor->GetClass()->Meta.GetMetaFixed(AMETA_FastSpeed, actor->Speed);
diff --git a/src/p_things.cpp b/src/p_things.cpp
index faf1091d5..3ca2164c4 100644
--- a/src/p_things.cpp
+++ b/src/p_things.cpp
@@ -86,7 +86,7 @@ bool P_Thing_Spawn (int tid, AActor *source, int type, angle_t angle, bool fog,
 
 		if (mobj != NULL)
 		{
-			DWORD oldFlags2 = mobj->flags2;
+			ActorFlags2 oldFlags2 = mobj->flags2;
 			mobj->flags2 |= MF2_PASSMOBJ;
 			if (P_TestMobjLocation (mobj))
 			{
@@ -429,7 +429,7 @@ bool P_Thing_Raise(AActor *thing, AActor *raiser)
 	// [RH] Check against real height and radius
 	fixed_t oldheight = thing->height;
 	fixed_t oldradius = thing->radius;
-	int oldflags = thing->flags;
+	ActorFlags oldflags = thing->flags;
 
 	thing->flags |= MF_SOLID;
 	thing->height = info->height;	// [RH] Use real height
@@ -468,7 +468,7 @@ bool P_Thing_CanRaise(AActor *thing)
 	AActor *info = thing->GetDefault();
 
 	// Check against real height and radius
-	int oldflags = thing->flags;
+	ActorFlags oldflags = thing->flags;
 	fixed_t oldheight = thing->height;
 	fixed_t oldradius = thing->radius;
 
diff --git a/src/r_main.cpp b/src/r_main.cpp
index dbf4cbeb5..5da0b8992 100644
--- a/src/r_main.cpp
+++ b/src/r_main.cpp
@@ -790,7 +790,7 @@ void R_RenderActorView (AActor *actor, bool dontmaplines)
 	P_FindParticleSubsectors ();
 
 	WallCycles.Clock();
-	DWORD savedflags = camera->renderflags;
+	ActorRenderFlags savedflags = camera->renderflags;
 	// Never draw the player unless in chasecam mode
 	if (!r_showviewer)
 	{
diff --git a/src/tflags.h b/src/tflags.h
new file mode 100644
index 000000000..20caba227
--- /dev/null
+++ b/src/tflags.h
@@ -0,0 +1,110 @@
+/*
+** tflags.h
+**
+**---------------------------------------------------------------------------
+** Copyright 2015 Teemu Piippo
+** All rights reserved.
+**
+** Redistribution and use in source and binary forms, with or without
+** modification, are permitted provided that the following conditions
+** are met:
+**
+** 1. Redistributions of source code must retain the above copyright
+**    notice, this list of conditions and the following disclaimer.
+** 2. Redistributions in binary form must reproduce the above copyright
+**    notice, this list of conditions and the following disclaimer in the
+**    documentation and/or other materials provided with the distribution.
+** 3. The name of the author may not be used to endorse or promote products
+**    derived from this software without specific prior written permission.
+**
+** THIS SOFTWARE IS PROVIDED BY THE AUTHOR ``AS IS'' AND ANY EXPRESS OR
+** IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES
+** OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE DISCLAIMED.
+** IN NO EVENT SHALL THE AUTHOR BE LIABLE FOR ANY DIRECT, INDIRECT,
+** INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT
+** NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE,
+** DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY
+** THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
+** (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF
+** THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
+**---------------------------------------------------------------------------
+**
+*/
+
+#pragma once
+#include "doomtype.h"
+
+/*
+ * TFlags
+ *
+ * A Qt-inspired type-safe flagset type.
+ *
+ * T is the enum type of individual flags,
+ * TT is the underlying integer type used (defaults to DWORD)
+ */
+template<typename T, typename TT = DWORD>
+class TFlags
+{
+	struct ZeroDummy {};
+
+public:
+	typedef TFlags<T, TT> Self;
+	typedef T EnumType;
+	typedef TT IntType;
+
+	TFlags(){}
+	TFlags (const Self& other) : Value (other.GetValue()) {}
+	TFlags (T value) : Value (static_cast<TT> (value)) {}
+
+	// This allows initializing the flagset with 0, as 0 implicitly converts into a null pointer.
+	TFlags (ZeroDummy*) : Value (0) {}
+
+	// Relation operators
+	Self operator| (Self other) const { return Self::FromInt (Value | other.GetValue()); }
+	Self operator& (Self other) const { return Self::FromInt (Value & other.GetValue()); }
+	Self operator^ (Self other) const { return Self::FromInt (Value ^ other.GetValue()); }
+	Self operator| (T value) const { return Self::FromInt (Value | value); }
+	Self operator& (T value) const { return Self::FromInt (Value & value); }
+	Self operator^ (T value) const { return Self::FromInt (Value ^ value); }
+	Self operator~() const { return Self::FromInt (~Value); }
+
+	// Assignment operators
+	Self& operator= (Self other) { Value = other.GetValue(); return *this; }
+	Self& operator|= (Self other) { Value |= other.GetValue(); return *this; }
+	Self& operator&= (Self other) { Value &= other.GetValue(); return *this; }
+	Self& operator^= (Self other) { Value ^= other.GetValue(); return *this; }
+	Self& operator= (T value) { Value = value; return *this; }
+	Self& operator|= (T value) { Value |= value; return *this; }
+	Self& operator&= (T value) { Value &= value; return *this; }
+	Self& operator^= (T value) { Value ^= value; return *this; }
+
+	// Access the value of the flagset
+	TT GetValue() const { return Value; }
+	operator TT() const { return Value; }
+
+	// Serialize to FArchive
+	FArchive& Serialize (FArchive& arc)
+	{
+		arc << Value;
+		return arc;
+	}
+
+	// Set the value of the flagset manually with an integer.
+	// Please think twice before using this.
+	static Self FromInt (TT value) { return Self (static_cast<T> (value)); }
+
+private:
+	TT Value;
+};
+
+/*
+ * Additional operators for TFlags types.
+ */
+#define DEFINE_TFLAGS_OPERATORS(T) \
+inline T operator| (T::EnumType a, T::EnumType b) { return T::FromInt (T::IntType (a) | T::IntType (b)); } \
+inline T operator& (T::EnumType a, T::EnumType b) { return T::FromInt (T::IntType (a) & T::IntType (b)); } \
+inline T operator^ (T::EnumType a, T::EnumType b) { return T::FromInt (T::IntType (a) ^ T::IntType (b)); } \
+inline T operator| (T::EnumType a, T b) { return T::FromInt (T::IntType (a) | T::IntType (b)); } \
+inline T operator& (T::EnumType a, T b) { return T::FromInt (T::IntType (a) & T::IntType (b)); } \
+inline T operator^ (T::EnumType a, T b) { return T::FromInt (T::IntType (a) ^ T::IntType (b)); } \
+inline T operator~ (T::EnumType a) { return T::FromInt (~T::IntType (a)); }
\ No newline at end of file
diff --git a/src/thingdef/thingdef_codeptr.cpp b/src/thingdef/thingdef_codeptr.cpp
index cb59f8a1f..3bb6061ba 100644
--- a/src/thingdef/thingdef_codeptr.cpp
+++ b/src/thingdef/thingdef_codeptr.cpp
@@ -2023,10 +2023,10 @@ static bool InitSpawnedItem(AActor *self, AActor *mo, int flags)
 		mo->RenderStyle = self->RenderStyle;
 	}
 	
-	if (flags & SIXF_TRANSFERSPRITEFRAME)
-	{
-		mo->sprite = self->sprite;
-		mo->frame = self->frame;
+	if (flags & SIXF_TRANSFERSPRITEFRAME)
+	{
+		mo->sprite = self->sprite;
+		mo->frame = self->frame;
 	}
 
 	if (flags & SIXF_TRANSFERROLL)
@@ -3766,7 +3766,7 @@ DEFINE_ACTION_FUNCTION_PARAMS(AActor, A_ChangeFlag)
 		}
 		else
 		{
-			DWORD *flagp = (DWORD*) (((char*)self) + fd->structoffset);
+			ActorFlags *flagp = (ActorFlags*) (((char*)self) + fd->structoffset);
 
 			// If these 2 flags get changed we need to update the blockmap and sector links.
 			bool linkchange = flagp == &self->flags && (fd->flagbit == MF_NOBLOCKMAP || fd->flagbit == MF_NOSECTOR);
@@ -4029,19 +4029,19 @@ DEFINE_ACTION_FUNCTION_PARAMS(AActor, A_SetPitch)
 	ref->SetPitch(pitch, !!(flags & SPF_INTERPOLATE));
 }
 
-//===========================================================================
-//
-// [Nash] A_SetRoll
-//
-// Set actor's roll (in degrees).
-//
-//===========================================================================
-
-DEFINE_ACTION_FUNCTION_PARAMS(AActor, A_SetRoll)
-{
-	ACTION_PARAM_START(3);
-	ACTION_PARAM_ANGLE(roll, 0);
-	ACTION_PARAM_INT(flags, 1);
+//===========================================================================
+//
+// [Nash] A_SetRoll
+//
+// Set actor's roll (in degrees).
+//
+//===========================================================================
+
+DEFINE_ACTION_FUNCTION_PARAMS(AActor, A_SetRoll)
+{
+	ACTION_PARAM_START(3);
+	ACTION_PARAM_ANGLE(roll, 0);
+	ACTION_PARAM_INT(flags, 1);
 	ACTION_PARAM_INT(ptr, 2);
 
 	AActor *ref = COPY_AAPTR(self, ptr);
@@ -4050,9 +4050,9 @@ DEFINE_ACTION_FUNCTION_PARAMS(AActor, A_SetRoll)
 	{
 		ACTION_SET_RESULT(false);
 		return;
-	}
-	ref->SetRoll(roll, !!(flags & SPF_INTERPOLATE));
-}
+	}
+	ref->SetRoll(roll, !!(flags & SPF_INTERPOLATE));
+}
 
 //===========================================================================
 //
diff --git a/src/thingdef/thingdef_data.cpp b/src/thingdef/thingdef_data.cpp
index e91c2ee65..cce1e623e 100644
--- a/src/thingdef/thingdef_data.cpp
+++ b/src/thingdef/thingdef_data.cpp
@@ -60,7 +60,7 @@ static TArray<FVariableInfo*> variables;
 #define DEFINE_DEPRECATED_FLAG(name) { DEPF_##name, #name, -1, 0 }
 #define DEFINE_DUMMY_FLAG(name) { DEPF_UNUSED, #name, -1, 0 }
 
-static FFlagDef ActorFlags[]=
+static FFlagDef ActorFlagDefs[]=
 {
 	DEFINE_FLAG(MF, PICKUP, APlayerPawn, flags),
 	DEFINE_FLAG(MF, SPECIAL, APlayerPawn, flags),
@@ -302,7 +302,7 @@ static FFlagDef ActorFlags[]=
 	DEFINE_DUMMY_FLAG(EXPLODEONDEATH),	    // seems useless
 };
 
-static FFlagDef InventoryFlags[] =
+static FFlagDef InventoryFlagDefs[] =
 {
 	// Inventory flags
 	DEFINE_FLAG(IF, QUIET, AInventory, ItemFlags),
@@ -329,7 +329,7 @@ static FFlagDef InventoryFlags[] =
 	DEFINE_DEPRECATED_FLAG(PICKUPFLASH),
 	DEFINE_DEPRECATED_FLAG(INTERHUBSTRIP),};
 
-static FFlagDef WeaponFlags[] =
+static FFlagDef WeaponFlagDefs[] =
 {
 	// Weapon flags
 	DEFINE_FLAG(WIF, NOAUTOFIRE, AWeapon, WeaponFlags),
@@ -356,7 +356,7 @@ static FFlagDef WeaponFlags[] =
 	DEFINE_DUMMY_FLAG(ALLOW_WITH_RESPAWN_INVUL),
 };
 
-static FFlagDef PlayerPawnFlags[] =
+static FFlagDef PlayerPawnFlagDefs[] =
 {
 	// PlayerPawn flags
 	DEFINE_FLAG(PPF, NOTHRUSTWHENINVUL, APlayerPawn, PlayerFlags),
@@ -364,7 +364,7 @@ static FFlagDef PlayerPawnFlags[] =
 	DEFINE_FLAG(PPF, CROUCHABLEMORPH, APlayerPawn, PlayerFlags),
 };
 
-static FFlagDef PowerSpeedFlags[] =
+static FFlagDef PowerSpeedFlagDefs[] =
 {
 	// PowerSpeed flags
 	DEFINE_FLAG(PSF, NOTRAIL, APowerSpeed, SpeedFlags),
@@ -372,11 +372,11 @@ static FFlagDef PowerSpeedFlags[] =
 
 static const struct FFlagList { const PClass *Type; FFlagDef *Defs; int NumDefs; } FlagLists[] =
 {
-	{ RUNTIME_CLASS(AActor), 		ActorFlags,		countof(ActorFlags) },
-	{ RUNTIME_CLASS(AInventory), 	InventoryFlags,	countof(InventoryFlags) },
-	{ RUNTIME_CLASS(AWeapon), 		WeaponFlags,	countof(WeaponFlags) },
-	{ RUNTIME_CLASS(APlayerPawn),	PlayerPawnFlags,countof(PlayerPawnFlags) },
-	{ RUNTIME_CLASS(APowerSpeed),	PowerSpeedFlags,countof(PowerSpeedFlags) },
+	{ RUNTIME_CLASS(AActor), 		ActorFlagDefs,		countof(ActorFlagDefs) },
+	{ RUNTIME_CLASS(AInventory), 	InventoryFlagDefs,	countof(InventoryFlagDefs) },
+	{ RUNTIME_CLASS(AWeapon), 		WeaponFlagDefs,		countof(WeaponFlagDefs) },
+	{ RUNTIME_CLASS(APlayerPawn),	PlayerPawnFlagDefs,	countof(PlayerPawnFlagDefs) },
+	{ RUNTIME_CLASS(APowerSpeed),	PowerSpeedFlagDefs,	countof(PowerSpeedFlagDefs) },
 };
 #define NUM_FLAG_LISTS (countof(FlagLists))
 
@@ -463,11 +463,11 @@ FFlagDef *FindFlag (const PClass *type, const char *part1, const char *part2)
 
 const char *GetFlagName(unsigned int flagnum, int flagoffset)
 {
-	for(unsigned i = 0; i < countof(ActorFlags); i++)
+	for(unsigned i = 0; i < countof(ActorFlagDefs); i++)
 	{
-		if (ActorFlags[i].flagbit == flagnum && ActorFlags[i].structoffset == flagoffset)
+		if (ActorFlagDefs[i].flagbit == flagnum && ActorFlagDefs[i].structoffset == flagoffset)
 		{
-			return ActorFlags[i].name;
+			return ActorFlagDefs[i].name;
 		}
 	}
 	return "(unknown)";	// return something printable
diff --git a/src/thingdef/thingdef_properties.cpp b/src/thingdef/thingdef_properties.cpp
index 95f1c463c..8b4ef305a 100644
--- a/src/thingdef/thingdef_properties.cpp
+++ b/src/thingdef/thingdef_properties.cpp
@@ -1050,7 +1050,7 @@ DEFINE_PROPERTY(bloodtype, Sss, Actor)
 DEFINE_PROPERTY(bouncetype, S, Actor)
 {
 	static const char *names[] = { "None", "Doom", "Heretic", "Hexen", "DoomCompat", "HereticCompat", "HexenCompat", "Grenade", "Classic", NULL };
-	static const int flags[] = { BOUNCE_None,
+	static const ActorBounceFlag flags[] = { BOUNCE_None,
 		BOUNCE_Doom, BOUNCE_Heretic, BOUNCE_Hexen,
 		BOUNCE_DoomCompat, BOUNCE_HereticCompat, BOUNCE_HexenCompat,
 		BOUNCE_Grenade, BOUNCE_Classic, };
@@ -1310,13 +1310,13 @@ DEFINE_PROPERTY(species, S, Actor)
 //==========================================================================
 DEFINE_PROPERTY(clearflags, 0, Actor)
 {
-	defaults->flags =
-		defaults->flags3 =
-		defaults->flags4 =
-		defaults->flags5 =
-		defaults->flags6 =
-		defaults->flags7 = 0;
+	defaults->flags = 0;
 	defaults->flags2 &= MF2_ARGSDEFINED;	// this flag must not be cleared
+	defaults->flags3 = 0;
+	defaults->flags4 = 0;
+	defaults->flags5 = 0;
+	defaults->flags6 = 0;
+	defaults->flags7 = 0;
 }
 
 //==========================================================================