From 1f2824e6143716ce347843d017753da3e96d3978 Mon Sep 17 00:00:00 2001
From: Paul Chote <pchote@users.noreply.github.com>
Date: Sun, 7 Aug 2016 19:28:28 +0100
Subject: [PATCH] Add WAngle.Lerp function.

---
 OpenRA.Game/WAngle.cs | 14 ++++++++++++++
 1 file changed, 14 insertions(+)

diff --git a/OpenRA.Game/WAngle.cs b/OpenRA.Game/WAngle.cs
index be63a238b7..4260b01149 100644
--- a/OpenRA.Game/WAngle.cs
+++ b/OpenRA.Game/WAngle.cs
@@ -64,6 +64,20 @@ namespace OpenRA
 			return new WAngle(Angle - 512).Tan();
 		}
 
+		public static WAngle Lerp(WAngle a, WAngle b, int mul, int div)
+		{
+			// Map 1024 <-> 0 wrapping into linear space
+			var aa = a.Angle;
+			var bb = b.Angle;
+			if (aa > bb && aa - bb > 512)
+				aa -= 1024;
+
+			if (bb > aa && bb - aa > 512)
+				bb -= 1024;
+
+			return new WAngle(aa + (bb - aa) * mul / div);
+		}
+
 		public static WAngle ArcTan(int y, int x) { return ArcTan(y, x, 1); }
 		public static WAngle ArcTan(int y, int x, int stride)
 		{