Glass material problem

Translucent object have to be fully rendered in front or behind other translucent objects, making this a very hard setup to render.

However, if you look at real wine bottles you’ll notice that due to the refraction of the glass you actually can’t see the thickness of the glass, instead the wine will appear to directly touch the outside of the bottle. You can use this to your advantage and just use a single object/material for both the glass and wine.