BEPUutilities.Matrix3x3.Determinant C# (CSharp) Метод

        public float Determinant()
        {
            return M11 * M22 * M33 + M12 * M23 * M31 + M13 * M21 * M32 -
                   M31 * M22 * M13 - M32 * M23 * M11 - M33 * M21 * M12;
        }

        /// <summary>
        /// Inverts the given matix.
        /// </summary>
        /// <param name="matrix">Matrix to be inverted.</param>
        /// <param name="result">Inverted matrix.</param>
        public static void Invert(ref Matrix3x3 matrix, out Matrix3x3 result)
        {
            float determinantInverse = 1 / matrix.Determinant();
            float m11 = (matrix.M22 * matrix.M33 - matrix.M23 * matrix.M32) * determinantInverse;
            float m12 = (matrix.M13 * matrix.M32 - matrix.M33 * matrix.M12) * determinantInverse;
            float m13 = (matrix.M12 * matrix.M23 - matrix.M22 * matrix.M13) * determinantInverse;

            float m21 = (matrix.M23 * matrix.M31 - matrix.M21 * matrix.M33) * determinantInverse;
            float m22 = (matrix.M11 * matrix.M33 - matrix.M13 * matrix.M31) * determinantInverse;
            float m23 = (matrix.M13 * matrix.M21 - matrix.M11 * matrix.M23) * determinantInverse;

            float m31 = (matrix.M21 * matrix.M32 - matrix.M22 * matrix.M31) * determinantInverse;
            float m32 = (matrix.M12 * matrix.M31 - matrix.M11 * matrix.M32) * determinantInverse;
            float m33 = (matrix.M11 * matrix.M22 - matrix.M12 * matrix.M21) * determinantInverse;

            result.M11 = m11;
            result.M12 = m12;
            result.M13 = m13;

            result.M21 = m21;
            result.M22 = m22;
            result.M23 = m23;

            result.M31 = m31;
            result.M32 = m32;
            result.M33 = m33;
        }