How can I create Indicators for the objects?

Hello friends, I am creating a game in that game, there are so many objects and for that I want to use indicator for different object like used in big game like GTA. for now I am using GUI.drawtexture to indicate the door and lift in my game but problem with this is when I move camera that texture X,y offset values should be change such that the indicating texture should be closer to that door or lift only. So how to do that? with GUI texture only or some other way?? Please help