Emacs — calculating new window-start/end without redisplay

Question

Is it possible to calculate a new window-start/end without a redisplay occurring? If so, then an example would be greatly appreciated. If not, th

Answer 1

I think you want to use jit-lock-register instead of post-command-hook. This way, the redisplay code will call you back once it has decided of a window-start and you'll be able to add the overlays you want before the buffer's content is displayed.