Hello all!
I need to make an object in my scene (a sphere) to “hole” all other objects, so to see the background through it (just what I can achieve with “matte material” in 3DSMax or in Blender). I try to explain better: imagine a few cubes around the scene, and a small sphere near the camera: well, this through this sphere I should see the backgound, also if the cubes are behind it.
Is it possible? I could not find anything about it on the web…
Many thanks!
From what you described, seems you’re looking for a material with envMap and refraction. 
I have 0-experience with 3DSMax and \varepsilon-experience with Blender. I have never seen the so called “matte material”, but is it something like this?
https://codepen.io/boytchev/full/wBWNXRL
5 Likes
Yes, it will show the background through it, but clip and be in 3d.
1 Like
The circular hole is a sphere. It does not cut closer objects. Here is with bars that distributed in front and behind the sphere:
2 Likes
colorWrite: false gives the same visual result 
2 Likes
Exactly 
you just need the depth basically.