Boxes linked by 'smart lines' - what's this called ? How's it done ?

Question

Terminology question !

In many graphics packages the user can draw a line between two objects (two boxes say) and then when the user moves one of the one boxes subseqently the line moves to keep the (visual) connection in place.

I want to learn more about this functionality might be implemented (really good to find some open source code to read).

So I want to find some terminology for what this type of stuff is called. I saw a reference on stackoverflow to 'wire-based drawing' but that seems to have been an invention of the author rather than a generally used term.

Is there a proper term for this area of graphics software technology ? Any open source libraries that implement it ?

thanks

Answer 1

I believe that most common name is "connectors". You can draw them using pathfinding algorithm (depends on how your objects are represented)

Here is an example of designer that implements what you described.

Answer 2

Diagrams - bloc, flowchart and so on. This type of drawings is usually created by software like Visio and Dia.

Btw, Dia is open source, so you can look at it to see how this is implemented.

Answer 3

These are connectors.

OpenOffice.org implements them. The feature is available in the Writer, Draw and Impress components (the Connectors menu on the Drawing toolbar). However, I have no idea how easy it would be to dig that feature out of their source code. Nevertheless, OpenOffice.org is open source.