# Question about example in geometry editor lecture

Here https://indico.cern.ch/event/1012211/contributions/4247790/attachments/2256346/3828710/05_Geometry_Editor_2021_online.pdf in example of zone editing there where are shown how to create sphere with a cylindrical hole cut with a tilted plane in part [1/9] for bodies sphere, infinite cylinder, tilted plane there are no selected materials. How it’s possible ? Also in part [2/9] said that “Select the material (or leave default VACUUM)”. If I select the material that would be material of what ? Cylinder, hole or what ? And what concrete characterize the created region in part [2/9] ?

I’ll try to address you question in order.

First of all, this is an example of geometry building using the geometry editor, therefore there is no need to specify which material precisely, any would do.
Second, to just separate the space in different regions, there is no real need to have regions of different material, could simply be logically different regions even if made of the same material.
Anyway, I stress this is an example.

It will be the material that you select, if you try to do the exercise, you’ll see in bottom left corner, in the “Properties and attributes listbox” that you can select the material. Don’t forget that Fluka already has some predefined materials, have a look at the Materials lecture, slide 4.

You need to go to the following slide [3/9], there it is written that you would have to select the sphere.

Here I’m at a loss. What do you mean?

I mean that if I set the value of material of this region to IRON, exactly what there will be from IRON ? Hole, sphere or what ?

It depends on which bodies you will select and which portion of space defined by those bodies you will select.
If you follow step by step, you will end selecting a zone that will belong to Region that you are editing, that Region will be made of IRON.