I'm looking for a diagramming program that can help in designing software, right from the high-level requirements down to the low-level classes and functions.
I've seen a lot of UML programs, but they don't let you design at multiple levels of detail in the same map, like if you could "zoom in" and design the details of a part.
Do programs exist that help in such designing? Programs that let you design at the high-level and low-level on the same map?