Too many objects need random emission values I'm new to blender, and am working on a large "cyberpunk" skyscraper that needs a ton of windows. I applied some basic materials nodes that randomized the emission values to each window as a separate object, which works great.  

However, the problem is that the picture shown is only a small fraction of the building, and when I'm putting the parts of the building together, the object count is reaching the thousands, and my computer slows to a crawl. Is there possibly an alternative to randomize whether each window is on or off that will remain once I combine them into a single object, or at least in bigger pieces? Maybe have each window be randomly assigned one of two materials? Any help would be greatly appreciated!
Thanks for your suggestion, but I figured out a different way to tackle the problem. I made all of the windows all as a separate object, and I discovered the random selection tool and randomly selected individual faces to be assigned to emission material