Here is the problem, I need to put an image "atop" of a co-ordinates area, and draw horizontal or vertical lines on the image's surface. Those lines must respond to mouse actions, like one could move them. And I always need to know on what co-ordinates my lines are, X for vertical lines and Y for horizontal. I'm a complete rookie in that area, might you suggest where to start to look on this topic? It appears to be easy to show a picture, or draw a line, but how to make them "alive" as described above? Thanks!
subject: creating lines a la Guide Lines in Photoshop