do glass windows affect performance yes it does well to a certain degree it depends if you're GPU bound or if you're CPU bound if you our game is tend to be very CPU bound so like if you have a big Factory you know it's usually the CPU that's slowing you down and if that's the case if the CPU is running faster than your GPU then it doesn't matter what happens on the GPU you might as well render like twice as much you know or make it as twice as detail or whatever so in that case it doesn't matter glass is transparent and transparency tend to be a lot more expensive to render than opaque items but seeing as how our game is mostly CPU bound it doesn't really affect it too much so yes