public void WorldToShade_AndBack_ShouldBeOriginalNormalized()
{
var normal = Vector3.Normalize(new Vector3(1, 5, 0));
var worldDir = Vector3.Normalize(new Vector3(1, 6, 2));
var shadeDir = ShadingSpace.WorldToShading(normal, worldDir);
var worldDir2 = ShadingSpace.ShadingToWorld(normal, shadeDir);
Assert.Equal(worldDir.X / worldDir.Length(), worldDir2.X, 4);
Assert.Equal(worldDir.Y / worldDir.Length(), worldDir2.Y, 4);
Assert.Equal(worldDir.Z / worldDir.Length(), worldDir2.Z, 4);
}
