UnityEngine.Matrix4x4.TransformDirection C# (CSharp) Method

        public Vector3 TransformDirection(Vector3 v)
        {
            return new Vector3(
                v.x * m00 + v.y * m01 + v.z * m02,
                v.x * m10 + v.y * m11 + v.z * m12,
                v.x * m20 + v.y * m21 + v.z * m22);
        }

        private static void AssertExpectedPlane(BoundedPlane plane, Vector3 bounds, Matrix4x4 vertDataTransform, Matrix4x4 meshTransform)
        {
            float expectedArea = 4.0f * bounds.x * bounds.y;
            Vector3 expectedPlaneNormal = meshTransform.TransformDirection(vertDataTransform.TransformDirection(new Vector3(0, 0, 1)));
            Vector3 expectedPlaneCenter = meshTransform.TransformPoint(vertDataTransform.TransformPoint(Vector3.zero));

            Assert.AreEqual(expectedArea, plane.Area, expectedArea * 0.01f);
            AssertAreEqual(expectedPlaneNormal, plane.Plane.normal, 0.01f, "Normal");
            AssertAreEqual(expectedPlaneCenter, plane.Bounds.Center, bounds.Length() * 0.01f, "Center");
        }