Welcome to the Sweet Home forum.
Probably the easiest way would be to model it in a 3D application, such as Art of Illusion, then import the model and build the rest of the bathroom scene from there.
Just built this glass door for you (attached to the end of this message), to help get you started.
If you would like a curved part for the shower base, have a look on the Sweet Home 3D models page, round wall part, I was going to use and adapt this, for the glass door, but it was too thick, so built a door using Art of Illusion instead.
Look forward to seeing your completed bathroom. [:)]
db4tech