I want to draw text just like the following style -- the image is always on the top right corner, and the text is around the image.
Yes, CoreText is the best way to do this. The code to do it is a little long to post here. Some code that may point you in the right direction is in the article "Clipping a CGRect to a CGPath." If the process for doing it is still confusing, ping me and I finally write the blog post I've been meaning to write on the subject.