Major Cooke: Added A_SpriteOffset

- Coordinates work akin to A_OverlayOffset: +X shifts to the right, +Y shifts down.

src/playsim/actor.h

@@ -989,6 +989,7 @@ public:
 
 	DVector3		OldRenderPos;
 	DVector3		Vel;
+	DVector2		SpriteOffset;
 	double			Speed;
 	double			FloatSpeed;
 

src/playsim/p_mobj.cpp

@@ -366,7 +366,8 @@ void AActor::Serialize(FSerializer &arc)
 		A("spawntime", SpawnTime)
 		A("spawnorder", SpawnOrder)
 		A("friction", Friction)
-		A("userlights", UserLights);
+		A("userlights", UserLights)
+		A("SpriteOffset", SpriteOffset);
 }
 
 #undef A

src/rendering/hwrenderer/scene/hw_sprites.cpp

@@ -847,11 +847,21 @@ void HWSprite::Process(HWDrawInfo *di, AActor* thing, sector_t * sector, area_t
 
 		r.Scale(sprscale.X, sprscale.Y);
 
-		float rightfac = -r.left;
+		// Disable this for flat/wall sprites. Facing sprites work just fine though.
+		float SOX = thing->SpriteOffset.X;
+		float SOY = thing->SpriteOffset.Y;
+
+		if (spritetype & (RF_FLATSPRITE | RF_WALLSPRITE))
+		{
+			SOX = 0.f;
+			SOY = 0.f;
+		}
+
+		float rightfac = -r.left - SOX;
 		float leftfac = rightfac - r.width;
 		float bottomfac = -r.top;
 		float topfac = bottomfac - r.height;
-		z1 = z - r.top;
+		z1 = z - r.top - SOY;
 		z2 = z1 - r.height;
 
 		float spriteheight = sprscale.Y * r.height;

src/rendering/polyrenderer/scene/poly_sprite.cpp

@@ -66,6 +66,10 @@ bool RenderPolySprite::GetLine(AActor *thing, DVector2 &left, DVector2 &right)
 	else
 		offsetX = tex->GetLeftOffsetPo() * thingxscalemul;
 
+	uint32_t type = (thing->renderflags & RF_SPRITETYPEMASK);
+	if (!(type & (RF_FLATSPRITE | RF_WALLSPRITE)))
+		offsetX -= thing->SpriteOffset.X;
+
 	left = DVector2(pos.X - viewpoint.Sin * offsetX, pos.Y + viewpoint.Cos * offsetX);
 	right = DVector2(left.X + viewpoint.Sin * spriteWidth, left.Y - viewpoint.Cos * spriteWidth);
 	return true;
@@ -115,6 +119,9 @@ void RenderPolySprite::Render(PolyRenderThread *thread, AActor *thing, subsector
 	posZ -= (tex->GetHeight() - tex->GetTopOffsetPo()) * thingyscalemul;
 	posZ = PerformSpriteClipAdjustment(thing, thingpos, spriteHeight, posZ);
 
+	if (!(spritetype & (RF_FLATSPRITE | RF_WALLSPRITE)))
+		posZ -= thing->SpriteOffset.Y;
+
 	//double depth = 1.0;
 	//visstyle_t visstyle = GetSpriteVisStyle(thing, depth);
 	// Rumor has it that AlterWeaponSprite needs to be called with visstyle passed in somewhere around here..

src/rendering/swrenderer/scene/r_opaque_pass.cpp

@@ -1005,6 +1005,11 @@ namespace swrenderer
 		sprite.pos = thing->InterpolatedPosition(Thread->Viewport->viewpoint.TicFrac);
 		sprite.pos.Z += thing->GetBobOffset(Thread->Viewport->viewpoint.TicFrac);
 
+		// The X offsetting is performed in r_sprite.cpp, in RenderSprite::Project().
+		uint32_t type = (thing->renderflags & RF_SPRITETYPEMASK);
+		if (!(type & (RF_FLATSPRITE | RF_WALLSPRITE)))
+			sprite.pos.Z -= thing->SpriteOffset.Y;
+
 		sprite.spritenum = thing->sprite;
 		sprite.tex = nullptr;
 		sprite.voxel = nullptr;

src/rendering/swrenderer/things/r_sprite.cpp

@@ -95,6 +95,11 @@ namespace swrenderer
 		}
 		//tx2 = tx >> 4;
 
+		// The Y offsetting is done in r_opaque_pass.cpp, in RenderOpaquePass::GetThingSprite().
+		uint32_t type = (thing->renderflags & RF_SPRITETYPEMASK);
+		if (!(type & (RF_FLATSPRITE | RF_WALLSPRITE)))
+			tx += thing->SpriteOffset.X;
+
 		// too far off the side?
 		if (fabs(tx / 64) > fabs(tz))
 		{

src/scripting/vmthunks_actors.cpp

@@ -1711,6 +1711,7 @@ DEFINE_FIELD_NAMED(AActor, __Pos, pos)
 DEFINE_FIELD_NAMED(AActor, __Pos.X, x)
 DEFINE_FIELD_NAMED(AActor, __Pos.Y, y)
 DEFINE_FIELD_NAMED(AActor, __Pos.Z, z)
+DEFINE_FIELD(AActor, SpriteOffset)
 DEFINE_FIELD(AActor, Prev)
 DEFINE_FIELD(AActor, SpriteAngle)
 DEFINE_FIELD(AActor, SpriteRotation)

wadsrc/static/zscript/actors/actions.zs

@@ -95,4 +95,9 @@ extend class Actor
 		}
 	}
 
+	void A_SpriteOffset(double ox = 0.0, double oy = 0.0)
+	{
+		SpriteOffset.X = ox;
+		SpriteOffset.Y = oy;
+	}
 }

wadsrc/static/zscript/actors/actor.zs

@@ -89,6 +89,7 @@ class Actor : Thinker native
 	native PlayerInfo Player;
 	native readonly vector3 Pos;
 	native vector3 Prev;
+	native vector2 SpriteOffset;
 	native double spriteAngle;
 	native double spriteRotation;
 	native double VisibleStartAngle;