Rendering text, is resource intensive. If you don't rotate or zoom, then most of the work can be cached (at least when using latin fonts with few ligatures) wh

Rendering text, is resource intensive. If you don't rotate or zoom, then most of the work can be cached (at least when using latin fonts with few ligatures) which make things appear to be fast, but if you tried to render text in real time without caching (because you're allowing rotation and zoom, and you can't cache everything) then you'd see how expensive it is.