From d06cba8263cc7b5a0b59b4d530043c67c1d6abad Mon Sep 17 00:00:00 2001
From: gered <gered@blarg.ca>
Date: Mon, 2 Sep 2013 14:14:25 -0400
Subject: [PATCH] add angle helper method

---
 Blarg.GameFramework/Math/MathHelpers.cs | 13 +++++++++++++
 1 file changed, 13 insertions(+)

diff --git a/Blarg.GameFramework/Math/MathHelpers.cs b/Blarg.GameFramework/Math/MathHelpers.cs
index 15fbf32..e40f4e8 100644
--- a/Blarg.GameFramework/Math/MathHelpers.cs
+++ b/Blarg.GameFramework/Math/MathHelpers.cs
@@ -86,6 +86,19 @@ namespace Blarg.GameFramework
 			return angle - MathConstants.Radians90;
 		}
 
+		/// <summary>
+		/// Returns the angle of rotation around the Y axis between the two
+		/// 3D points. This is calculated by only looking at the X and Z
+		/// components of each point.
+		/// </summary>
+		/// <returns>The angle of rotation (in radians) around the Y axis between the two points</returns>
+		/// <param name="a">The first point</param>
+		/// <param name="b">The second point</param>
+		public static float GetYAngleBetweenPoints(Vector3 a, Vector3 b)
+		{
+			return GetAngleBetweenPoints(a.X, a.Z, b.X, b.Z);
+		}
+
 		/// <summary>
 		/// Solves a quadratic equation and returns the lowest root.
 		/// </summary>