Generally, I use louvered shutters on my windows to keep out unwanted heat.
At my office, I made a roll down external shade from this
ClearDome Solar Thermal fabrics for cooling and heating over a big plate glass window which faces south. I Use it doubled, it hangs from an externally mounted bracket, where the open end of the folded material are fixed to a board, (attached to the bracket), mounted horizontally as a header over the window. I inserted a broom handle in the fold of the material to weight it & keep it from blowing up. It has been in operation for 12 years without problem. In the fall, when I want solar gain, I simply roll up & tie the material; no muss - no fuss. It seem impervious to the weather.
A pergola would work as well.