by Rodrigo Duarte:
We will use a Boolean Subtraction for the broken glass and a Boolean Intersection for the piece that broke off.
Let us start with a glass.
To create the “break” let us draw a profile with the 2D pen tool and extrude it. Let us position it so that it intersects one of the walls of the glass.
We need two copies of the glass and the break object. Let us group the glass and break object and then copy and paste the group.
Double click to edit the first group.
Select the Subtact tool and click on the extruded object. Drag over the glass until both the extruded object and the glass are highlighted in red.
For the broken piece do the same with the other group, only performing an Intersection this time.
Now place the broken piece lying on the floor, make sure both objects have a glass texture applied and render.
That’s a basic broken glass.
The next step would be detailing the broken edges.