Monday night I had a migraine. I hadn't had one for awhile. That night I tried to rough out where my vision was. All of my vision was blurry, but much of it was also just flat out gone. The above isn't meant to be the start of a drawing or anything. The purple was roughly where my vision cut off and the white was roughly where I could see. This was roughed out at mostly full screen on a 21 in. monitor at approximately 3 feet from the monitor. At the time, I pretty much had no vision just a few inches to the right in my right eye, and it was difficult to see in the center of my focus.
I tried to keep a log during my migraine, as my brain is a little loopy whenever they occur, and I never really can fully describe them once they have left. I thought it was interesting trying to describe the effects.