I'm not even sure how to describe this. I was working on a multi-level image and tried to select part of it in order to copy and paste. The selection had a lot of missed areas, all geometric in form. Then I tried to change the fill color on the background layer, and the geometric areas appeared in bright colors. I can't fill or paint over them, and when I tried to paste in a new layer the geometric patterns erased the parts that they covered. The file size is well within the capabilities of my setup as I've successfully worked on much larger files recently. I'm not seeing any video problems in any other program, so I don't think it's a card problem. I'm completely baffled.
Did you close and restart PS yet?
Yes, with no effect. I went back to CC (the problem occurred in CC 2014) and redid my project with no problems. Maybe CC 2014 still has some bugs?