In the city I live, there is a small building with a relatively new parabolic glass front that focuses roughly onto the pavement in front - in the winter it's r

In the city I live, there is a small building with a relatively new parabolic glass front that focuses roughly onto the pavement in front - in the winter it's rather pleasant to walk through, the summer not so much. This is only a small effect though, I imagine with larger buildings it's never desirable.