Application of Zoning Heights to Land Contour

Most diagrams that I've seen depicting zoning heights and setbacks are shown on flat land. The Marshall Tract is far from flat. It has a pretty interesting contour. I know that somehow the city accounts for this be applying some averaging technique, but I was curious to see what the heights and setback would look like for various types of zoning, and assuming that the heights are measured from the elevation of Quaker Ridge. What I got is shown below.

GO is General Office, the base zoning planned by Cousins for the PUD (with lots of variances). The East Riverside Corridor is an example of how Austin handled heights and setbacks for better compatibility. The distance scale goes from zero at Quaker Ridge to 2000 at Loop 360 (approximately).

I don't know how Austin will handle the heights and setbacks for the Marshall Tract. But, it should be a strong discussion point for us, after we see what staff recommends.