[Uml-devel] Improved line-object handling in Umbrello

[mike wakerly]

Hello Umbrello folk,

I've just started using Umbrello, and overall it is a very nice package for 
KDE. It does just what I'm looking for (UML and State Machine diagrams), and 
the interface is pretty elegant.

However, I have just one complaint, and after only a few hours of use, it is 
turning in to a big one: line segments. The way in which line segments are 
handled is often extremely frustrating.

A cursory look doesn't show much discussion of the way line objects are 
handled whilst diagramming, and I notice that the changelog only lists 
multi-segment lines as a relatively new feature.

My first problem is that the current auto-positioning algorithm for lines 
(associations, dependencies, etc, state transitions, and all other line 
types) is inadequate for typical diagrams. When non-line diagram objects 
(such as a state box) have more than one or two anchored lines, the 
autopositioning is often not what you'd like; I get criss-crossed lines all 
the time that can only be corrected by jiggling one state around another, 
hoping that Umbrello will recalculate the line anchors in the fashion I want. 
At present I do not see how to move the line anchors, but if someone can tell 
me I'd much appreciate it.

(One state I drew up had five possible outgoing states; the desired result was 
a star-like layout that was very precarious to maintain in Umbrello.)

I would also like to see support for 'square-line' types. I am not sure of the 
precise name, but such a line would behave differently that the current line 
does. Such a line would only allow strictly horizontal and strictly vertical 
segments. When you move an object horizontally that is anchored with a 
square-line, the horizontal segment resizes.

In Umbrello, you can painstakingly create square connecting lines by breaking 
a vanilla line into multiple segments. But as soon as an anchored object is 
moved, the breakpoint in the line remains fixed whilst the closest segment is 
resized to take the shortest path between the breakpoint and the object. (In 
a square-line, the movement would cause the nearest horizontal and vertical 
segments to be resized appropriately.

I am by no means an old hat with diagramming, but I would hope this 
improvement is seen as a necessary improvement in diagramming mode. I'd like 
to know if there is any work going on presently on improving the line 
object..

Otherwise, thanks very much for a very promising package.

Take care,
Mike Wakerly


--
mike wakerly, usc computer engineering class of 2003
http://hoho.com/mike