Draw sprite shadows for monsters and players by default, and allow ac…

…tor overrides for them.

src/playsim/actor.h

@@ -412,6 +412,8 @@ enum ActorFlag8
 	MF8_RETARGETAFTERSLAM	= 0x00000080,	// Forces jumping to the idle state after slamming into something
 	MF8_RECREATELIGHTS	= 0x00000100,	// Internal flag that signifies that the light attachments need to be recreated at the
 	MF8_STOPRAILS		= 0x00000200,	// [MC] Prevent rails from going further if an actor has this flag.
+	MF8_CASTSPRITESHADOW	= 0x00000400, // Sprite shadow overrides
+	MF8_NOSPRITESHADOW		= 0x00000800, // Ditto
 };
 
 // --- mobj.renderflags ---

src/rendering/swrenderer/scene/r_opaque_pass.cpp

@@ -970,7 +970,8 @@ namespace swrenderer
 						bool drawSpriteShadows =
 						(
 							r_actorshadows &&
-							((thing->flags3 & MF3_ISMONSTER) || thing->IsKindOf(NAME_PlayerPawn))
+							((thing->flags3 & MF3_ISMONSTER) || thing->IsKindOf(NAME_PlayerPawn) || (thing->flags8 & MF8_CASTSPRITESHADOW)) &&
+							!(thing->flags8 & MF8_NOSPRITESHADOW)
 						);
 
 						if (drawSpriteShadows)

src/scripting/thingdef_data.cpp

@@ -325,6 +325,8 @@ static FFlagDef ActorFlagDefs[]=
 	DEFINE_FLAG(MF8, NOFRICTIONBOUNCE, AActor, flags8),
 	DEFINE_FLAG(MF8, RETARGETAFTERSLAM, AActor, flags8),
 	DEFINE_FLAG(MF8, STOPRAILS, AActor, flags8),
+	DEFINE_FLAG(MF8, CASTSPRITESHADOW, AActor, flags8),
+	DEFINE_FLAG(MF8, NOSPRITESHADOW, AActor, flags8),
 
 	// Effect flags
 	DEFINE_FLAG(FX, VISIBILITYPULSE, AActor, effects),