Distortions like these? https://en.wikipedia.org/wiki/Scintillating_scotoma
More like shifting bubbles Transparent version of https://static.brusheezy.com/system/resources/previews/000/0...
Or if I have an eye stroke going on, then a black shifting mass in center of vision.
Get lots of other interesting effects, but usually only if I take a break from blood thinners.