Add UseClassicFacingFudge flag for TD/RA.

OpenRA.Mods.Common/Graphics/DefaultSpriteSequence.cs

@@ -75,7 +75,7 @@ namespace OpenRA.Mods.Common.Graphics
 	{
 		static readonly WDist DefaultShadowSpriteZOffset = new WDist(-5);
 		readonly Sprite[] sprites;
-		readonly bool reverseFacings, transpose;
+		readonly bool reverseFacings, transpose, useClassicFacingFudge;
 
 		protected readonly ISpriteSequenceLoader Loader;
 
@@ -129,6 +129,8 @@ namespace OpenRA.Mods.Common.Graphics
 				Tick = LoadField(d, "Tick", 40);
 				transpose = LoadField(d, "Transpose", false);
 				Frames = LoadField<int[]>(d, "Frames", null);
+				useClassicFacingFudge = LoadField(d, "UseClassicFacingFudge", false);
+
 				var flipX = LoadField(d, "FlipX", false);
 				var flipY = LoadField(d, "FlipY", false);
 
@@ -139,6 +141,11 @@ namespace OpenRA.Mods.Common.Graphics
 					Facings = -Facings;
 				}
 
+				if (useClassicFacingFudge && Facings != 32)
+					throw new InvalidOperationException(
+						"{0}: Sequence {1}.{2}: UseClassicFacingFudge is only valid for 32 facings"
+						.F(info.Nodes[0].Location, sequence, animation));
+
 				var offset = LoadField(d, "Offset", float2.Zero);
 				var blendMode = LoadField(d, "BlendMode", BlendMode.Alpha);
 
@@ -237,8 +244,7 @@ namespace OpenRA.Mods.Common.Graphics
 
 		protected virtual Sprite GetSprite(int start, int frame, int facing)
 		{
-			var f = Util.QuantizeFacing(facing, Facings);
-
+			var f = Util.QuantizeFacing(facing, Facings, useClassicFacingFudge);
 			if (reverseFacings)
 				f = (Facings - f) % Facings;
 

OpenRA.Mods.Common/Traits/BodyOrientation.cs

@@ -24,6 +24,9 @@ namespace OpenRA.Mods.Common.Traits
 		[Desc("Fudge the coordinate system angles like the early games.")]
 		public readonly bool UseClassicPerspectiveFudge = true;
 
+		[Desc("Fudge the coordinate system angles like the early games.")]
+		public readonly bool UseClassicFacingFudge = false;
+
 		public WVec LocalToWorld(WVec vec)
 		{
 			// Rotate by 90 degrees
@@ -50,7 +53,7 @@ namespace OpenRA.Mods.Common.Traits
 
 		public int QuantizeFacing(int facing, int facings)
 		{
-			return Util.QuantizeFacing(facing, facings) * (256 / facings);
+			return Util.QuantizeFacing(facing, facings, UseClassicFacingFudge) * (256 / facings);
 		}
 
 		public object Create(ActorInitializer init) { return new BodyOrientation(init, this); }

OpenRA.Mods.Common/Util.cs

@@ -48,6 +48,30 @@ namespace OpenRA.Mods.Common
 			return a / step;
 		}
 
+		public static int QuantizeFacing(int facing, int numFrames, bool useClassicFacingFudge)
+		{
+			if (!useClassicFacingFudge || numFrames != 32)
+				return Util.QuantizeFacing(facing, numFrames);
+
+			// TD and RA divided the facing artwork into 3 frames from (north|south) to (north|south)-(east|west)
+			// and then 5 frames from (north|south)-(east|west) to (east|west)
+			var quadrant = ((facing + 31) & 0xFF) / 64;
+			if (quadrant == 0 || quadrant == 2)
+			{
+				var frame = Util.QuantizeFacing(facing, 24);
+				if (frame > 18)
+					return frame + 6;
+				if (frame > 4)
+					return frame + 3;
+				return frame;
+			}
+			else
+			{
+				var frame = Util.QuantizeFacing(facing, 40);
+				return frame < 20 ? frame - 3 : frame - 8;
+			}
+		}
+
 		public static WPos BetweenCells(World w, CPos from, CPos to)
 		{
 			return WPos.Lerp(w.Map.CenterOfCell(from), w.Map.CenterOfCell(to), 1, 2);