I'm making a dictionary app, which allows user find a word definition by touch the word in screen, and there will be a magnifier on screen and follow user's finger. I have implement it by take a screenshot of view and assign the image to maginifer image view, which is a UIImageView, however, in order to take a screenshot, the method [self.layer renderInContext:c]; cost too much time, is there any other way to do it ?maybe openGL will help?
after profiling my app with instruments->core animation, it is only 9 fps showing magnifier, but it will 30 fps if showing the system default magnifier in a UITextView, I don't know why the system is so fast
You can use exact same view in magnifier view, and change position to visible words.