Some useful C# methods for various mathematical purposes (such as 2D/3D math and complex operations)

ACMath.cs

/// <summary>
/// Determines if a Vector2 point is within a triangle
/// </summary>
/// <param name="point">Point to check</param>
/// <param name="p0">Triangle vertex position</param>
/// <param name="p1">Triangle vertex position</param>
/// <param name="p2">Triangle vertex position</param>
/// <returns>True if point is inside triangle, otherwise false</returns>
/// <remarks>
/// Uses barycentric coordinate computation
/// </remarks>
public static bool PointInTriangle( Vector2 point, Vector2 p0, Vector2 p1, Vector2 p2 )
{
        var s = (p0.x - p2.x) * (point.y - p2.y) - (p0.y - p2.y) * (point.x - p2.x);
        var t = (p1.x - p0.x) * (point.y - p0.y) - (p1.y - p0.y) * (point.x - p0.x);

        if ( (s < 0) != (t < 0) && s != 0 && t != 0 ) return false;

        var d = (p2.x - p1.x) * (point.y - p1.y) -
                 (p2.y - p1.y) * (point.x - p1.x);

        return d == 0 || (d < 0) == (s + t <= 0);
}

Will share any clever math tricks for C#/game dev I think of here ...