Displaying an Image

Hello all,

I'm trying to work on a little project, but need to do a couple of things that I don't know how to do. If anybody could set me on the right path I would appreciate it. I need to display an image on the screen first off. Then I need to have the user click on a couple of points and have some sort of symbol that makes it clear where they clicked. Lastly the user needs to be able to click and drag a visible rectangle over an area of the image.

Sorry if this is a stupid question, but it would be great if you could give me a hand. I've just never done anything with a gui before. Oh and by the way, I'll be using codex to compile.

Thanks
Evan

More details.

What is your OS
What in the world is codex
What is this 'image'

Anything else that would help us help you is good.

The operating system is OS X. CodeX is a sort of development suite for it. I'm more used to Linux, but I'm working in a lab and it is the only option I have. By image I mean a picture. Most of the work in this program is actually going to be done in MatLab I just need the user to point out a few things about the image first. Thanks.

Isn't it X Code?

Try searching google.