- Splitting the pull request in half.

- Added THRUREFLECT, MIRRORREFLECT, and AIMREFLECT. All require REFLECTIVE to work.
- THRUREFLECT prevents missiles from changing course if reflected, and takes precedence over all reflective flags.
- MIRRORREFLECT causes missiles to perform a direct 180 turn-around.
- AIMREFLECT turns the missile back to the original shooter, and does not slow the missile down.

src/actor.h

@@ -347,6 +347,11 @@ enum
 	MF7_DONTTHRUST		= 0x00000100,	// Thrusting functions do not take, and do not give thrust (damage) to actors with this flag.
 	MF7_ALLOWPAIN		= 0x00000200,	// Invulnerable or immune (via damagefactors) actors can still react to taking damage even if they don't.
 	MF7_CAUSEPAIN		= 0x00000400,	// Damage sources with this flag can cause similar effects like ALLOWPAIN.
+	MF7_THRUREFLECT		= 0x00000800,	// Actors who are reflective cause the missiles to not slow down or change angles.
+	MF7_MIRRORREFLECT	= 0x00001000,	// Actor is turned directly 180 degrees around when reflected.
+	MF7_AIMREFLECT		= 0x00002000,	// Actor is directly reflected straight back at the one who fired the projectile.
+
+
 
 // --- mobj.renderflags ---
 
@@ -859,7 +864,7 @@ public:
 	DWORD			flags4;			// [RH] Even more flags!
 	DWORD			flags5;			// OMG! We need another one.
 	DWORD			flags6;			// Shit! Where did all the flags go?
-	DWORD			flags7;			// 
+	DWORD			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;

src/p_map.cpp

@@ -1283,6 +1283,16 @@ bool PIT_CheckThing(AActor *thing, FCheckPosition &tm)
 		{
 			P_GiveBody(thing, -damage);
 		}
+
+		if ((thing->flags7 & MF7_THRUREFLECT) && (thing->flags2 & MF2_REFLECTIVE) && (tm.thing->flags & MF_MISSILE))
+		{
+			if (tm.thing->flags2 & MF2_SEEKERMISSILE)
+			{
+				tm.thing->tracer = tm.thing->target;
+			}
+			tm.thing->target = thing;
+			return true;
+		}
 		return false;		// don't traverse any more
 	}
 	if (thing->flags2 & MF2_PUSHABLE && !(tm.thing->flags2 & MF2_CANNOTPUSH))
@@ -1643,7 +1653,7 @@ bool P_TestMobjZ(AActor *actor, bool quick, AActor **pOnmobj)
 		{ // Don't clip against self
 			continue;
 		}
-		if ((actor->flags & MF_MISSILE) && thing == actor->target)
+		if ((actor->flags & MF_MISSILE) && (thing == actor->target))
 		{ // Don't clip against whoever shot the missile.
 			continue;
 		}
@@ -2983,18 +2993,20 @@ bool P_BounceWall(AActor *mo)
 extern FRandom pr_bounce;
 bool P_BounceActor(AActor *mo, AActor *BlockingMobj, bool ontop)
 {
+	//Don't go through all of this if the actor is reflective and wants things to pass through them.
+	if (BlockingMobj && ((BlockingMobj->flags2 & MF2_REFLECTIVE) && (BlockingMobj->flags7 & MF7_THRUREFLECT))) return true;
 	if (mo && BlockingMobj && ((mo->BounceFlags & BOUNCE_AllActors)
-		|| ((mo->flags & MF_MISSILE) && (!(mo->flags2 & MF2_RIP) || (BlockingMobj->flags5 & MF5_DONTRIP) || ((mo->flags6 & MF6_NOBOSSRIP) && (BlockingMobj->flags2 & MF2_BOSS))) && (BlockingMobj->flags2 & MF2_REFLECTIVE))
+		|| ((mo->flags & MF_MISSILE) && (!(mo->flags2 & MF2_RIP) 
-		|| ((BlockingMobj->player == NULL) && (!(BlockingMobj->flags3 & MF3_ISMONSTER)))
+		|| (BlockingMobj->flags5 & MF5_DONTRIP) 
-		))
+		|| ((mo->flags6 & MF6_NOBOSSRIP) && (BlockingMobj->flags2 & MF2_BOSS))) && (BlockingMobj->flags2 & MF2_REFLECTIVE))
+		|| ((BlockingMobj->player == NULL) && (!(BlockingMobj->flags3 & MF3_ISMONSTER)))))
 	{
 		if (mo->bouncecount > 0 && --mo->bouncecount == 0) return false;
 
 		if (!ontop)
 		{
 			fixed_t speed;
-			angle_t angle = R_PointToAngle2(BlockingMobj->x,
+			angle_t angle = R_PointToAngle2(BlockingMobj->x,BlockingMobj->y, mo->x, mo->y) + ANGLE_1*((pr_bounce() % 16) - 8);
-				BlockingMobj->y, mo->x, mo->y) + ANGLE_1*((pr_bounce() % 16) - 8);
 			speed = P_AproxDistance(mo->velx, mo->vely);
 			speed = FixedMul(speed, mo->wallbouncefactor); // [GZ] was 0.75, using wallbouncefactor seems more consistent
 			mo->angle = angle;
@@ -5090,6 +5102,8 @@ int P_PushUp(AActor *thing, FChangePosition *cpos)
 		// is normally for projectiles which would have exploded by now anyway...
 		if (thing->flags6 & MF6_THRUSPECIES && thing->GetSpecies() == intersect->GetSpecies())
 			continue;
+		if ((thing->flags & MF_MISSILE) && (intersect->flags2 & MF2_REFLECTIVE) && (intersect->flags7 & MF7_THRUREFLECT))
+			continue;
 		if (!(intersect->flags2 & MF2_PASSMOBJ) ||
 			(!(intersect->flags3 & MF3_ISMONSTER) && intersect->Mass > mymass) ||
 			(intersect->flags4 & MF4_ACTLIKEBRIDGE)
@@ -5098,7 +5112,8 @@ int P_PushUp(AActor *thing, FChangePosition *cpos)
 			// Can't push bridges or things more massive than ourself
 			return 2;
 		}
-		fixed_t oldz = intersect->z;
+		fixed_t oldz;
+		oldz = intersect->z;
 		P_AdjustFloorCeil(intersect, cpos);
 		intersect->z = thing->z + thing->height + 1;
 		if (P_PushUp(intersect, cpos))

src/p_mobj.cpp

@@ -1660,6 +1660,7 @@ fixed_t P_XYMovement (AActor *mo, fixed_t scrollx, fixed_t scrolly)
 	int steps, step, totalsteps;
 	fixed_t startx, starty;
 	fixed_t oldfloorz = mo->floorz;
+	fixed_t oldz = mo->z;
 
 	fixed_t maxmove = (mo->waterlevel < 1) || (mo->flags & MF_MISSILE) || 
 					  (mo->player && mo->player->crouchoffset<-10*FRACUNIT) ? MAXMOVE : MAXMOVE/4;
@@ -1949,20 +1950,53 @@ fixed_t P_XYMovement (AActor *mo, fixed_t scrollx, fixed_t scrolly)
 				}
 				if (BlockingMobj && (BlockingMobj->flags2 & MF2_REFLECTIVE))
 				{
-					angle = R_PointToAngle2(BlockingMobj->x, BlockingMobj->y, mo->x, mo->y);
+					bool seeker = (mo->flags2 & MF2_SEEKERMISSILE) ? true : false;
-
+					// Don't change the angle if there's THRUREFLECT on the monster.
-					// Change angle for deflection/reflection
+					if (!(BlockingMobj->flags7 & MF7_THRUREFLECT))
-					if (mo->AdjustReflectionAngle (BlockingMobj, angle))
 					{
-						goto explode;
+						int dir;
-					}
+						angle_t delta;
+						
+						if (BlockingMobj->flags7 & MF7_MIRRORREFLECT)
+							angle = mo->angle + ANG180;
+						else
+							angle = R_PointToAngle2(BlockingMobj->x, BlockingMobj->y, mo->x, mo->y);
 
-					// Reflect the missile along angle
+						// Change angle for deflection/reflection
-					mo->angle = angle;
+						// AIMREFLECT calls precedence so make sure not to bother with adjusting here if declared.
-					angle >>= ANGLETOFINESHIFT;
+						if (!(BlockingMobj->flags7 & MF7_AIMREFLECT) && (mo->AdjustReflectionAngle(BlockingMobj, angle)))
-					mo->velx = FixedMul (mo->Speed>>1, finecosine[angle]);
+						{
-					mo->vely = FixedMul (mo->Speed>>1, finesine[angle]);
+							goto explode;
-					mo->velz = -mo->velz/2;
+						}
+
+						// Reflect the missile along angle
+						if (BlockingMobj->flags7 & MF7_AIMREFLECT)
+						{
+							dir = P_FaceMobj(mo, mo->target, &delta);
+							if (dir)
+							{ // Turn clockwise
+								mo->angle += delta;
+							}
+							else
+							{ // Turn counter clockwise
+								mo->angle -= delta;
+							}
+							angle = mo->angle >> ANGLETOFINESHIFT;
+							mo->velx = FixedMul(mo->Speed, finecosine[angle]);
+							mo->vely = FixedMul(mo->Speed, finesine[angle]);
+							mo->velz = -mo->velz;
+						}
+						else
+						{
+							mo->angle = angle;
+							angle >>= ANGLETOFINESHIFT;
+							mo->velx = FixedMul(mo->Speed >> 1, finecosine[angle]);
+							mo->vely = FixedMul(mo->Speed >> 1, finesine[angle]);
+							mo->velz = -mo->velz / 2;
+						}
+						
+						
+					}
 					if (mo->flags2 & MF2_SEEKERMISSILE)
 					{
 						mo->tracer = mo->target;
@@ -2893,6 +2927,7 @@ int AActor::SpecialMissileHit (AActor *victim)
 bool AActor::AdjustReflectionAngle (AActor *thing, angle_t &angle)
 {
 	if (flags2 & MF2_DONTREFLECT) return true;
+	if (thing->flags7 & MF7_THRUREFLECT) return false;
 
 	// Change angle for reflection
 	if (thing->flags4&MF4_SHIELDREFLECT)

src/thingdef/thingdef_data.cpp

@@ -247,6 +247,9 @@ static FFlagDef ActorFlags[]=
 	DEFINE_FLAG(MF7, DONTTHRUST, AActor, flags7),
 	DEFINE_FLAG(MF7, ALLOWPAIN, AActor, flags7),
 	DEFINE_FLAG(MF7, CAUSEPAIN, AActor, flags7),
+	DEFINE_FLAG(MF7, THRUREFLECT, AActor, flags7),
+	DEFINE_FLAG(MF7, MIRRORREFLECT, AActor, flags7),
+	DEFINE_FLAG(MF7, AIMREFLECT, AActor, flags7),
 
 	// Effect flags
 	DEFINE_FLAG(FX, VISIBILITYPULSE, AActor, effects),