How would these stay up?

I’ve made an ‘armless’ sketch of big glasses. I was just trying out some textures in my sketchbook app.

Do you know you can tell if someone is short or long sighted depending on whether their eyes look bigger (long sighted) or smaller (short sighted). That is dependent on the convex or concave nature of the lenses in their glasses.

If you are very short sighted your eyes will look smaller than if you are only mildly affected. It also depends on whether your spectacle lenses are made of glass or plastic.

If you ever watch a TV programme or film with an actor wearing glasses then look at the lenses. If the light catches them you can see if the glass is flat, then you know they don’t really need glasses!