If a guy says that you are pretty it does not mean that he likes you. He could like you, or he could just be paying you a compliment.
That he's got good eyesight
I means that you are special to him and that you are very pretty
If a guy says that he thinks you will look pretty in a dress, he means that the dress will best bring out(magnify) your beauty.
It only means the guy is ugly for you or the guy does not have a big account in the bank.
He pretty much told you with what he said...
It means he thinks your pretty obviously but he might like you or hes just a nice guy who likes to compliment people.
Bill says, "Taimoor is a real tall guy."
Well to start it means he thinks your pretty, to answer the other half of the question it means you don't have to be friendly or have any real personality at all to get guys interested in you.
hes calling you pretty or he likes you
I'd say no
It can mean that the guy that told you is joking around about the crush thing or he can be serious but revealing his friend's secrets out just for fun and games. So it can pretty much mean anything on that part.