Refactored IQuantizeBodyOrientation implementation

Moved BodyOrientation and related interfaces from Game to Mods.Common.
Introduced QuantizeFacingsFromSequence trait.
With*Body render traits no longer implement IQuantizeBodyOrientation
themselves.

OpenRA.Mods.Common/Traits/BodyOrientation.cs

@@ -0,0 +1,99 @@
+#region Copyright & License Information
+/*
+ * Copyright 2007-2015 The OpenRA Developers (see AUTHORS)
+ * This file is part of OpenRA, which is free software. It is made
+ * available to you under the terms of the GNU General Public License
+ * as published by the Free Software Foundation. For more information,
+ * see COPYING.
+ */
+#endregion
+
+using System;
+using System.Collections.Generic;
+using System.Linq;
+using OpenRA.Traits;
+
+namespace OpenRA.Mods.Common.Traits
+{
+	public class BodyOrientationInfo : ITraitInfo, IBodyOrientationInfo
+	{
+		[Desc("Number of facings for gameplay calculations. -1 indicates auto-detection from another trait")]
+		public readonly int QuantizedFacings = -1;
+
+		[Desc("Camera pitch for rotation calculations")]
+		public readonly WAngle CameraPitch = WAngle.FromDegrees(40);
+
+		[Desc("Fudge the coordinate system angles like the early games.")]
+		public readonly bool UseClassicPerspectiveFudge = true;
+
+		public WVec LocalToWorld(WVec vec)
+		{
+			// Rotate by 90 degrees
+			if (!UseClassicPerspectiveFudge)
+				return new WVec(vec.Y, -vec.X, vec.Z);
+
+			// RA's 2d perspective doesn't correspond to an orthonormal 3D
+			// coordinate system, so fudge the y axis to make things look good
+			return new WVec(vec.Y, -CameraPitch.Sin() * vec.X / 1024, vec.Z);
+		}
+
+		public WRot QuantizeOrientation(WRot orientation, int facings)
+		{
+			// Quantization disabled
+			if (facings == 0)
+				return orientation;
+
+			// Map yaw to the closest facing
+			var facing = Util.QuantizeFacing(orientation.Yaw.Angle / 4, facings) * (256 / facings);
+
+			// Roll and pitch are always zero if yaw is quantized
+			return new WRot(WAngle.Zero, WAngle.Zero, WAngle.FromFacing(facing));
+		}
+
+		public object Create(ActorInitializer init) { return new BodyOrientation(init, this); }
+	}
+
+	public class BodyOrientation : IBodyOrientation
+	{
+		readonly BodyOrientationInfo info;
+		readonly Lazy<int> quantizedFacings;
+
+		[Sync] public int QuantizedFacings { get { return quantizedFacings.Value; } }
+
+		public BodyOrientation(ActorInitializer init, BodyOrientationInfo info)
+		{
+			this.info = info;
+			var self = init.Self;
+			var faction = init.Contains<FactionInit>() ? init.Get<FactionInit, string>() : self.Owner.Faction.InternalName;
+
+			quantizedFacings = Exts.Lazy(() =>
+			{
+				// Override value is set
+				if (info.QuantizedFacings >= 0)
+					return info.QuantizedFacings;
+
+				var qboi = self.Info.Traits.GetOrDefault<IQuantizeBodyOrientationInfo>();
+				var isb = self.HasTrait<ISpriteBody>();
+
+				// If a sprite actor has neither custom QuantizedFacings nor a trait implementing IQuantizeBodyOrientationInfo, throw
+				if (qboi == null && isb)
+					throw new InvalidOperationException("Actor" + self.Info.Name + "has a sprite body but no facing quantization."
+						+ " Either add the QuantizeFacingsFromSequence trait or set custom QuantizedFacings on BodyOrientation.");
+
+				return qboi.QuantizedBodyFacings(self.Info, self.World.Map.SequenceProvider, faction);
+			});
+		}
+
+		public WAngle CameraPitch { get { return info.CameraPitch; } }
+
+		public WVec LocalToWorld(WVec vec)
+		{
+			return info.LocalToWorld(vec);
+		}
+
+		public WRot QuantizeOrientation(Actor self, WRot orientation)
+		{
+			return info.QuantizeOrientation(orientation, quantizedFacings.Value);
+		}
+	}
+}