Aded FLIPSPRITEOFFSET<X/Y> for actors and bFlipOffset<X/Y> for visual thinkers.

- Inverts the direction that (Sprite)Offset pushes the sprite without affecting *any* other offsets, allowing them to combine seemlessly.

src/playsim/actor.h

@@ -498,6 +498,8 @@ enum ActorRenderFlag2
 	RF2_ONLYVISIBLEINMIRRORS	= 0x0002,	// [Nash] only renders in mirrors
 	RF2_BILLBOARDFACECAMERA		= 0x0004,	// Sprite billboard face camera (override gl_billboard_faces_camera)
 	RF2_BILLBOARDNOFACECAMERA	= 0x0008,	// Sprite billboard face camera angle (override gl_billboard_faces_camera)
+	RF2_FLIPSPRITEOFFSETX		= 0x0010,
+	RF2_FLIPSPRITEOFFSETY		= 0x0020,
 };
 
 // This translucency value produces the closest match to Heretic's TINTTAB.
@@ -1472,6 +1474,11 @@ public:
 		result.Roll = PrevAngles.Roll + deltaangle(PrevAngles.Roll, Angles.Roll) * ticFrac;
 		return result;
 	}
+	float GetSpriteOffset(bool y) const
+	{
+		if (y)	return (float)(renderflags2 & RF2_FLIPSPRITEOFFSETY ? SpriteOffset.Y : -SpriteOffset.Y);
+		else	return (float)(renderflags2 & RF2_FLIPSPRITEOFFSETX ? SpriteOffset.X : -SpriteOffset.X);
+	}
 	DAngle GetSpriteAngle(DAngle viewangle, double ticFrac)
 	{
 		if (flags7 & MF7_SPRITEANGLE)

src/playsim/p_effect.cpp

@@ -1206,7 +1206,7 @@ DEFINE_ACTION_FUNCTION_NATIVE(DVisualThinker, SetTranslation, SetTranslation)
 
 static int IsFrozen(DVisualThinker * self)
 {
-	return (self->Level->isFrozen() && !(self->PT.flags & SPF_NOTIMEFREEZE));
+	return !!(self->Level->isFrozen() && !(self->PT.flags & SPF_NOTIMEFREEZE));
 }
 
 bool DVisualThinker::isFrozen()
@@ -1242,6 +1242,14 @@ int DVisualThinker::GetRenderStyle()
 	return PT.style;
 }
 
+float DVisualThinker::GetOffset(bool y) const // Needed for the renderer.
+{
+	if (y)
+		return (float)(bFlipOffsetY ? Offset.Y : -Offset.Y);
+	else
+		return (float)(bFlipOffsetX ? Offset.X : -Offset.X);
+}
+
 void DVisualThinker::Serialize(FSerializer& arc)
 {
 	Super::Serialize(arc);
@@ -1264,6 +1272,8 @@ void DVisualThinker::Serialize(FSerializer& arc)
 		("flipy", bYFlip)
 		("dontinterpolate", bDontInterpolate)
 		("addlightlevel", bAddLightLevel)
+		("flipoffsetx", bFlipOffsetX)
+		("flipoffsetY", bFlipOffsetY)
 		("lightlevel", LightLevel)
 		("flags", PT.flags);
 		
@@ -1289,3 +1299,5 @@ DEFINE_FIELD(DVisualThinker, bXFlip);
 DEFINE_FIELD(DVisualThinker, bYFlip);
 DEFINE_FIELD(DVisualThinker, bDontInterpolate);
 DEFINE_FIELD(DVisualThinker, bAddLightLevel);
+DEFINE_FIELD(DVisualThinker, bFlipOffsetX);
+DEFINE_FIELD(DVisualThinker, bFlipOffsetY);

src/playsim/p_effect.h

@@ -166,7 +166,9 @@ public:
 	FTextureID		AnimatedTexture;
 	sector_t		*cursector;
 
-	bool			bXFlip,
+	bool			bFlipOffsetX,
+					bFlipOffsetY,
+					bXFlip,
 					bYFlip,				// flip the sprite on the x/y axis.
 					bDontInterpolate,	// disable all interpolation
 					bAddLightLevel;		// adds sector light level to 'LightLevel'
@@ -191,4 +193,5 @@ public:
 	void UpdateSpriteInfo();
 	void Serialize(FSerializer& arc) override;
 
-};
+	float GetOffset(bool y) const;
+};

src/rendering/hwrenderer/scene/hw_sprites.cpp

@@ -414,7 +414,7 @@ bool HWSprite::CalculateVertices(HWDrawInfo* di, FVector3* v, DVector3* vp)
 	const bool isWallSprite = (actor != nullptr) && (spritetype == RF_WALLSPRITE);
 	const bool useOffsets = (actor != nullptr) && !(actor->renderflags & RF_ROLLCENTER);
 
-	FVector2 offset = FVector2( -offx, -offy );
+	FVector2 offset = FVector2( offx, offy );
 
 	// Account for +ROLLCENTER flag. Takes the embedded image offsets and adds them in with SpriteOffsets.
 	if (drawRollSpriteActor && useOffsets)
@@ -961,8 +961,8 @@ void HWSprite::Process(HWDrawInfo *di, AActor* thing, sector_t * sector, area_t
 		if (!tex || !tex->isValid()) return;
 		auto& spi = tex->GetSpritePositioning(type == RF_FACESPRITE);
 
-		offx = (float)thing->SpriteOffset.X;
-		offy = (float)thing->SpriteOffset.Y;
+		offx = (float)thing->GetSpriteOffset(false);
+		offy = (float)thing->GetSpriteOffset(true);
 
 		vt = spi.GetSpriteVT();
 		vb = spi.GetSpriteVB();
@@ -1491,8 +1491,8 @@ void HWSprite::AdjustVisualThinker(HWDrawInfo* di, DVisualThinker* spr, sector_t
 	y = interp.Y;
 	z = interp.Z;
 
-	offx = (float)spr->Offset.X;
-	offy = (float)spr->Offset.Y;
+	offx = (float)spr->GetOffset(false);
+	offy = (float)spr->GetOffset(true);
 
 	if (spr->PT.flags & SPF_ROLL)
 		Angles.Roll = TAngle<double>::fromDeg(spr->InterpolatedRoll(timefrac));

src/rendering/swrenderer/scene/r_opaque_pass.cpp

@@ -1046,7 +1046,7 @@ namespace swrenderer
 		// The X offsetting (SpriteOffset.X) is performed in r_sprite.cpp, in RenderSprite::Project().
 		sprite.pos = thing->InterpolatedPosition(Thread->Viewport->viewpoint.TicFrac);
 		sprite.pos += thing->WorldOffset;
-		sprite.pos.Z += thing->GetBobOffset(Thread->Viewport->viewpoint.TicFrac) - thing->SpriteOffset.Y;
+		sprite.pos.Z += thing->GetBobOffset(Thread->Viewport->viewpoint.TicFrac) + thing->GetSpriteOffset(true);
 		sprite.spritenum = thing->sprite;
 		sprite.tex = nullptr;
 		sprite.voxel = nullptr;

src/rendering/swrenderer/things/r_sprite.cpp

@@ -81,7 +81,7 @@ namespace swrenderer
 		const double thingxscalemul = spriteScale.X / tex->GetScale().X;
 
 		// Calculate billboard line for the sprite
-		double SpriteOffX = (thing) ? thing->SpriteOffset.X : 0.;
+		double SpriteOffX = (thing) ? -thing->GetSpriteOffset(false) : 0.;
 		DVector2 dir = { viewport->viewpoint.Sin, -viewport->viewpoint.Cos };
 		DVector2 trs = pos.XY() - viewport->viewpoint.Pos.XY();
 		trs = { trs.X + SpriteOffX * dir.X, trs.Y + SpriteOffX * dir.Y };

src/scripting/thingdef_data.cpp

@@ -381,6 +381,8 @@ static FFlagDef ActorFlagDefs[]=
 	DEFINE_FLAG(RF2, ONLYVISIBLEINMIRRORS, AActor, renderflags2),
 	DEFINE_FLAG(RF2, BILLBOARDFACECAMERA, AActor, renderflags2),
 	DEFINE_FLAG(RF2, BILLBOARDNOFACECAMERA, AActor, renderflags2),
+	DEFINE_FLAG(RF2, FLIPSPRITEOFFSETX, AActor, renderflags2),
+	DEFINE_FLAG(RF2, FLIPSPRITEOFFSETY, AActor, renderflags2),
 
 	// Bounce flags
 	DEFINE_FLAG2(BOUNCE_Walls, BOUNCEONWALLS, AActor, BounceFlags),

wadsrc/static/zscript/visualthinker.zs

@@ -12,7 +12,9 @@ Class VisualThinker : Thinker native
 	native TranslationID	Translation;
 	native uint16			Flags;
 	native int16			LightLevel;
-	native bool				bXFlip,
+	native bool				bFlipOffsetX,
+							bFlipOffsetY,
+							bXFlip,
 							bYFlip,
 							bDontInterpolate,
 							bAddLightLevel;