Install drapery rod at just below ceiling height and wide enough to allow drapes to beclear of the sliding glass doors when drapery is fully open; in other words, treat the arched window and the glass doors as if it’s one large window .

looking at photo again and realizing you may not have ceiling clearance to do what I suggested.

Thanks Weathy! I just added a second photo. What do you think?

Looking at your setup from that second angle suggests you’d have proper clearance on the left but now I wonder about the right side The space on the right is limited by the protruding fireplace “trim” (the mini “hood” above the fireplace opening and the detail below the opening).

To see what might work you could purchase a 96” or 104” drapery panel, (whatever appropriate length) hold it up at height rod would be, and see if it hangs ok. Does it look squished, left to right by the fireplace? Does it hang freely? A heavier fabric panel will take up more soace, especially if it’s lined. Maybe a cotton canvas but no lining, or a blackout panel would fit.

To help you decide about adequate space, consider the function of the slider. Do you open it a lot? Is that outdoor space a spot you use all the time, or does the door stay primarily closed and youre not going theough that door much. The right panel could hang partially over the door handle (door seldom opened) or it could hang so it fuly clears the door handle (use door all the time).

Alternatively, you could mount a shade over the arched window that is long enogh to cover the sliders when shade is let down. (Prob requires a custom made at this length). Whether a shade or drapery, the slider door handle and limited width and height of space will inform your decision as Im sure you already know. Either woud work, but neither are ”perfect”. But perfect is seldom needed.

The pros have great advice; maybe they‘ll weigh in

You either mount the rod above or below the arch.

love rod all the way above half moon window. brings eye up. you could put a window film on half window,