KOffice: Summer of Code Students Deliver the Goods

Under the KDE umbrella, the KOffice project took part in the <a href=""http://code.google.com/summerofcode.html>2006 Summer of Code with four participants. And not only that, but the Dutch Programmeerzomer, sponsored by Finalist, also selected a KOffice project. The summer is over, the season of mists and long hacking nights has arrived and the question that's obviously in everyone's mind is, have these five delivered? -- and, more importantly, will Gabor, Alfredo, Emanuele, Thomas and Fredrik continue hacking on KOffice?

Emanuele Tamponi: Krita

Emanuele Tamponi

Emanuele Tamponi, an 18 year old student from Calangianus, Sardinia had the ambitious plan to add three important features to Krita:

• a bezier curve tool with stroking using Krita brushes
• a selection tool based on the bezier curve painting tool
• a magnetic outline selection tool

Emanuele himself says:

My SoC application was split in 3 parts: firstly I had to code a framework to handle curves (that are lists of points, managed by "special points" or "pivots"); then I had to deploy a tool for Bezier Curves and for Magnetic Outline Selection based on the Framework.

Bezier Curves are curves created by applying a recursive function on a set of up to four points: the result is a smooth curve, ideal for all types of design (from cars to fonts...).

Magnetic Outline Selection (MOS for short) is like the "Magnetic Lasso" tool from Photoshop or the "Select part of the image" (Scissors tool) from the GIMP. My MOS just behaves better than both:

First I compared two tools for the "intelligent scissors": Photoshop one and gimp's one.

1) Photoshop follows your mouse while *moving* (not just dragging) it, adding other control points when the mouse is getting too far from the last control point. This way, it can be fast (just small area of the image are computed) and precise (because it *follows* the mouse, so it follows the edge that *you* want to select).

2) Gimp does it in a more "standard" way: it calculates the edge between two clicks of the mouse. It's fast because it calculate the edge only once per click, but it's not precise because you can't see the curve generated *while* you follow the edge.

But gimp gives you the possibility to *edit* (moving or deleting) already inserted control points, whereas Photoshop can only delete the last inserted control point, without other types of editing *during* the line makeup (with Photoshop you can edit the control points *after* you close the curve, and this is not always the right solution).

My MOS mixes both: it follows the mouse as Photoshop does, but if you want to edit a control point, you just hit "Ctrl" and you switch to Editing Mode, then edit, add or delete the control point you want, and when you're done, you can either it "Ctrl" again to return to "Automatic (Photoshop-like) Mode", or hit "Enter" or the button on the Options Widget to end the selection.

Emanuele was mentored by Bart Coppens and did indeed finish his project on time and on spec, and is now getting ready to port his work to KOffice 2.0. His tools will first be release in KOffice 1.6 -- real soon now!

Alfredo Beaumont: KFormula

Alfredo Beaumont

Alfredo Beaumont Sainz, from Gasteiz, Basque Country, worked on adding MathML to Kformula. He studies telematics and philosophy:

My SoC project consisted in adding full native support of MathML / OpenDocument format to KFormula. There were also some related tasks that needed to be accomplished, such as improving mathematical font support, rewriting user interface to take advantage of new functionalities allowed by MathML and extending / rewriting old native format code for backwards compatibility.

I think that project was quite successful, even if I haven't reach 100% of the objectives. We have now native support of both MathML and OpenDocument, with an internal layout that resembles very well these formats' layout. We have achieved nearly full support (more than 70% of tests passed, comparing to 20% of old KFormula and 22% of OOMath2). New font engine has been developed, replacing old TeX font support with new Unicode font support. KFormula now includes Arev fonts with great mathematical support by Tavmjong Bah, and allows the user to choose whichever Unicode font they have installed. That's all I did during SoC period, but till then I have been working in the fourth task, and some UI changes have already been added. All these features can be seen in action in KOffice 1.6 beta that will be released in a week. Still improved MathML / ODF support, refined UI and extended old format are expected for final 1.6 release.

A preview of the work done can be seen in the screenshot: Navier's equation with each part of the equation highlighted with a different background.

Alfredo is now the official maintainer of KFormula. His mentor was David Faure.

Fredrik Edemar: KWord

Fredrik Edemar, a computer science student from Uppsala, Sweden. has have worked on two smaller projects: automatic heading recognition in KWord and version support for all KOffice applications. Both these new features will be included in KOffice 2.0.

KWord now recognizes headings and puts them in a tree view. This makes it easier for a user to get an overview of large documents. From the list, it is possible to move and delete headings.

Version support can be very handy if several people are writing in one document. Let us assume that the first user saves the file, and the next wants to make changes. Then she can create a new version with the old content, do her changes and finally save her work. In that way it is possible to later go back and see what the first writer saved. The versions are off course stored in the OpenDocument file format.

Fredrik was mentored by Boudewijn Rempt. As soon as the current sweeping redesign of KWord's frame system is done, Fredrik will port the header feature to KWord 2.0; the versions feature was developed in 2.0 already.

Gábor Lehel, KOffice core

Mentored by Cyrille Berger, Gabor Lehel coded a second-generation widget for all of KOffice, based on his work for Krita's layers widget.

Many of KOffice's applications use a similar concept for dividing documents up into parts. Krita and Karbon have layers, KPresenter has slides, KWord has pages. I wrote a widget to display a list of these in a uniform way across KOffice 2.0 applications.

It is implemented as a QAbstractItemDelegate and likely a QAbstractItemView subclass, and each application can provide their own QAbstractItemModel subclass, tailored to the application's data format. Two main view modes have been created: a thumbnail view with only large thumbnails and possibly a name / label below them (as in KPDF), which would be most suitable for KWord and KPresenter, and a detailed view, with smaller thumbnails and information next to them, including editable properties (as in Krita 1.5), which would be most suitable for Krita, Karbon and Kivio. But all applications can show both modes, so it's possible to get really large layer previews in Krita or detailed meta information about pages in KWord.

Thomas Schaap: KOffice Core

Thomas Schaap studies in Delft, the Netherlands and was selected by Finalist to participate in the Dutch Programmeerzomer. Having wanted to work on KOffice for quite some time, he grabbed this opportunity to really get into KOffice. Brad Hards was the real, practical mentor, while Boudewijn Rempt was his pro-forma mentor.

The project was to provide support for encrypted documents in KOffice. The big difficulty, which is still not completely solved, is compatibility with OpenOffice encrypted documents. Thomas not only had to learn KOffice and its development culture, but also needed to learn about OpenOffice and find his way on their mailing lists. And then, of course, Thomas needed to work in KOffice trunk. The day his project began was also, coincidentally, the first day that KOffice 2.0 actually compiled against KDE 4!

But despite these difficulties and a very tight schedule, he managed to finish all core functionality and get it checked in -- as Thomas says himself: "I did a good job of, the KOffice guys are really happy with what I did." Next stage: signed documents!

Conclusion

Five projects, five successes! Thanks Thomas, Gábor, Fredrik, Alfredo and Emanuele for your work, and thanks Google and Finalist for organizing these projects!