public void Triangle_GetNormalAtPoint_returns_normalised_vector() { var p1 = new Point(0.0f, 0.0f, 0.0f); var p2 = new Point(1.0f, 0.0f, 0.0f); var p3 = new Point(1.0f, 1.0f, 0.0f); var t = new Triangle(p1, p2, p3); var actual = t.GetNormalAtPoint(new Point(0.5f, 0.5f, 0.0f)); Assert.AreEqual(1.0f, actual.Norm(), EPSILON); }