Source code visualization tools?

[Joel Konkle-Parker]

Is there such a thing as a source code visualization tool that makes a
"map" of a program's source? Kind of like:

main()
                |
                |
             function1()
                /\
               /  \
         func2()   func3()
            |
            |
          func4()

I'm basically looking for something that will help me "see" how a
program is laid out so that I can start working on it.

Thanks in advance.