When I Create Photo I see my ground texture extend all the way to the horizon...

How do I either adjust the Horizon or force the ground texture to match that of my floor plan?

I also would like to put a photo of my view from my apartment out the window but when I import it as a texture. The bottom of the image is displayed at the horizon... So knowing how to adjust the horizon would be helpful too...

I couldn't find anything in the help or the forums on this.

Thanks!