Is A Guy Interested In A Girl If He Checks Her Out Or Looks At Her From Head To Toe?

I went to a restaurant earlier today and I noticed this guy kept looking at my face as I was heading in his direction for a couple of seconds. Then later, I saw him look at some other people and then he looks back at me from head to toe-he was literally scanning my body. After he was done, he kept looking at the floor/ground like he was thinking about something. Was he interested? I mean, I was not wearing anything revealing.