public void RightVectorFromNegativeNormalTest() { // gleaned from https://github.com/ixmilia/dxf/issues/105 // A 90 degree arc from 270-360 degrees with a negative Z normal is displayed by both AutoCAD and Teigha in Q3. var right = DxfVector.RightVectorFromNormal(new DxfVector(0.0, 0.0, -1.0)); var expected = -DxfVector.XAxis; Assert.Equal(expected, right); }