This layer allow to generate geometries that are not polygonal but ray-traced. Which mean there are things you can do only with them, some others not.
By default, after creating this one, you'll see nothing in your Viewport
Although this layer does not use a Surface
, it uses it's components (such as bump/normal map etc...)
Now first thing to do is to create geometries inside of this layer by right clicking on it :
The special thing about this layer is that here geometries can be blended. Here I made my sphere intersecting with the box
And here I subtracted the sphere from the box. As you can guess, many possibilities exists.
Now all you have to do is to add some Constructive Geometry Modifiers and there you go !