Supplement to 3vi1 FNA fixes

MonoGame.Framework/BoundingFrustum.cs

@@ -209,8 +209,13 @@ public void Contains(ref Vector3 point, out ContainmentType result)
 		{
 			for (int i = 0; i < PlaneCount; i += 1)
 			{
-				// TODO: we might want to inline this for performance reasons
-				if (PlaneHelper.ClassifyPoint(ref point, ref this.planes[i]) > 0)
+				float classifyPoint = (
+					(point.X * planes[i].Normal.X) +
+					(point.Y * planes[i].Normal.Y) +
+					(point.Z * planes[i].Normal.Z) +
+					planes[i].D
+				);
+				if (classifyPoint > 0)
 				{
 					result = ContainmentType.Disjoint;
 					return;

MonoGame.Framework/Color.cs

@@ -1879,7 +1879,7 @@ public override string ToString()
 		#endregion
 	}
 
-	#region XNAColorConverter Class
+	#region Color TypeConverter
 
 	public class XNAColorConverter : TypeConverter
 	{

MonoGame.Framework/MathHelper.cs

@@ -143,9 +143,11 @@ float amount
 			double amountCubed = amountSquared * amount;
 			return (float) (
 				0.5 *
-				(2.0 * value2 +	(value3 - value1) * amount +
-				(2.0 * value1 - 5.0 * value2 + 4.0 * value3 - value4) * amountSquared +
-				(3.0 * value2 - value1 - 3.0 * value3 + value4) * amountCubed)
+				(
+					((2.0 * value2 + (value3 - value1) * amount) +
+					((2.0 * value1 - 5.0 * value2 + 4.0 * value3 - value4) * amountSquared) +
+					(3.0 * value2 - value1 - 3.0 * value3 + value4) * amountCubed)
+				)
 			);
 		}
 
@@ -241,9 +243,9 @@ float amount
 			else
 			{
 				result = (
-				        (2 * v1 - 2 * v2 + t2 + t1) * sCubed +
-				        (3 * v2 - 3 * v1 - 2 * t1 - t2) * sSquared +
-				        t1 * s +
+				        ((2 * v1 - 2 * v2 + t2 + t1) * sCubed) +
+				        ((3 * v2 - 3 * v1 - 2 * t1 - t2) * sSquared) +
+				        (t1 * s) +
 				        v1
 				);
 			}