The Grumpy Editor's diagram editor followup

Kivio had actually been considered for the previous article. Your editor, however, had seen a tool which, apparently, could only draw lines and text. Thinking that kivio must be a little too young for a real review, your editor set it aside and moved on. Kivio users will understand the problem at this point: your editor missed the little icon (shown at left) in the toolbar which loads stencils into the system. Kivio, the main purpose of which is the creation of flowcharts, is all about stencils. A large set of stencils is provided with the program; they include the full library of shapes from Dia, national flags, a map of Belgium, UML symbols, and "people shapes" including a woman in a bikini. Working with kivio is really a matter of finding the stencils you like, dragging them onto the screen, and drawing lines between them.

Strangely, there seems to be no mechanism built into kivio for the creation and editing of stencils; they all would appear to come from the outside. Nothing in the menus or online documentation says anything about how to get stencils into the system. Unless, of course, you want to buy the proprietary stencil builder or get some stencils on a per-seat license from theKompany.com.

Kivio has a number of the features your editor was looking for, including layers, attachment points, etc. But the simple fact is that kivio is an awkward and difficult tool to work with. Attributes (colors, line widths, arrowheads, etc.) must be set individually for every object; there appears to be no way to get kivio to apply user-specified attributes to new objects. There is no way to adjust the dimensions of arrowheads (and, interestingly, the "start arrowhead" appears at the second point of the connector). Connectors can only be straight lines. Alignment operations are done via a separate, popup dialog. The "docker" feature, which puts tools like the layer manager on the edge of the diagram, looks cute, but the tools are forever popping in and out when the diagram is being edited. Kivio cannot export to an image file; it is limited to KOffice format or (via the print operation) PostScript or PDF.

Kivio is a reasonable tool for some simple tasks now, and may well develop into a capable, general-purpose diagram editor eventually. But it is not up to your editor's needs at this time.

Skencil (formerly "sketch") was highly recommended by some LWN commenters. Skencil, in its stable version, is a Tk-based vector drawing package. This tool is currently being reworked to use GTK instead, but that version is not yet ready for release. Skencil has many of the typical drawing functions, and it supports layers. It does not support attachment points, and it cannot export to image formats.

Once again, your editor found this tool to be awkward and frustrating to work with. The interface is highly modal and confusing at times. Changing the default attributes of objects is hard. The arc-drawing tool is very confusing to use at the outset (though, once you get the hang of it, it turns out to be a powerful tool). The alignment operations require dealing with a separate dialog.

On the other hand, skencil has some slick features, such as the ability to draw text along an arbitrary path. There is a plugin mechanism allowing the addition of new features programmed in Python. Skencil also can import images in a number of formats. It may well be a useful tool for those engaged in more artistic pursuits; it is not, however, the best diagramming tool out there.

Finally, your editor took a look at inkscape. As a drawing tool, inkscape has a nice feature set; it has a reasonable set of drawing options, a full set of path operations, etc. Perhaps the biggest omission is the lack of support for layers. For the creation of diagrams, however, inkscape is not the right tool. There are no attachment points, no arrowheads, and no image export. Inkscape's priorities are simply elsewhere.

Worth a quick mention: if your main interest is the creation of UML diagrams, Umbrello may be worth checking out. It is, however, very much a special-purpose tool, with UML assumptions wired deeply into it; as such, it's not suitable for more general purpose diagramming.

To conclude: your editor will stick with dia for now for his cheesy diagram creation needs. Of all the tools reviewed, dia stands out for its focus on this particular task, the quality of its output, and its ease of use. There is a lot of development happening in this area, however; the situation could well be different next year.