Graphics for c++

Question

I have this truss-solver implementation in c++ which, for a given truss and boundary conditions, it calculates the displacements at the joints, and the stress at the elements. So at the end of the run, the console will display something like this:

 -Node-    -Disp.-
    1        0.50
    2        0.04
    3        1.21

-Element-  -Stress-
    1       121.50
    2        99.14
    3       144.09

I would like to plot that results to see the deformed structure on the screen, for example: http://www.aem.umn.edu/people/faculty/shield/software/truss/main12.gif

or

http://upload.wikimedia.org/wikipedia/commons/thumb/3/3a/Deformframe.JPG/750px-Deformframe.JPG

My knowledge of how to implement that kind of graphics is zero. So a solution that is easy to implement, or fast/easy to learn will be appreciated. By the way, I'm using CodeBlocks for Windows, and i would like the final application to be cross platform.

If there's something i'm not taking into account or you have other suggestions, i would like to know them.

Thanks.