Last year I published some Writer training slides, which are hopefully a useful extension to in-tree documentation like sw/README and sw/qa/extras/README.

Last week I reviewed those slides and realized that some of them are outdated. So here comes an updated version:

• first part, up to, but not including layout
• second part, starting from the layout

The intention is that these build nicely on top of Michael's generic intro slides, and with that, the reader can have a good "big picture" understanding of the code base. For the gory details, you always need to read the code anyway. ;-)

I've arrived home yesterday from Zagreb where I gave a keynote at CLUC 2014 on Tuesday.

Here are a few talks I enjoyed:

• Dave Whiteland's mysociety.org talk
• Harald Welte's osmocom.org talk
• Elizabeth Krumbach Joseph's OpenStack talk (explaining how do they use gerrit, git-review and related tools)

I also took a panorama and some pictures, available here, including photos of some speakers.

Thanks Elizabeth for the above photo, and also to the organizers of the conference, it was a great one! ;-)

Shapes in Writer are provided by LibreOffice's drawing layer -- they are independent from the normal Writer paragraphs. Given that the drawing layer does not support tracking changes, just Writer's "native" paragraphs, fully featured tracked changes in real shape text would be quite some work. In case of ODF, the markup describes tracked changes in a way, so that in case the reader does not support tracking changes, it can at least read the normal and inserted text, i.e. the current version.

This is exactly what I implemented in the DOCX import filter now:

Previously we just ignored both inserted and deleted text, so if you had content which was all either deleted or inserted, you ended up having no shape text at all (can be tested using e.g. this test document):

To be fair, the reference layout looks like this:

I still hope to fix that as well one day, but the above fix is something we'll already provide in 4.3. :-)

OTRS is quite different to Bugzilla (what we use for upstream LibreOffice development for quite some time). On the plus side, e.g. it has strong support for multiple customers. OTOH, it deals with tickets instead of bugs, and sadly it doesn't have a single identifier for tickets. It has a ticket number (which by default even includes the date), which is searchable, and it has a ticket ID, which is used for URL's.

In case of Bugzilla, you can easily lookup "bug#12345" in Firefox. Create a bookmark with the following properties:

• Location: https://localhost/bugzilla/show_bug.cgi?id=%s
• Keyword: bug

and then you can just copy&paste bug#12345 to Firefox, replace the # with a space, and Firefox will do the right thing.

Unfortunately (due to the above detailed reasons), this is not possible with OTRS. So I decided to write a Supybot plugin that can notice "bug#12345" on an IRC channel, and give you the clickable URL (after finding out the ticket ID from the ticket number).

The result is available on GitHub, it looks like this:

09:58 < vmiklos> bug#1000068
09:58 < supybot> https://localhost/otrs/index.pl?Action=AgentTicketZoom;TicketID=73

Given that I found no relevant hits when searching for 'supybot otrs', I hope this code may be useful for others as well.

Thanks to James Scott for his YouTube plugin that helped to quickly figure out the relevant Supybot API's.

When using text frames in Writer, you can always choose if you set an absolute size for it or you set a relative one. Oddly enough, in case of relative sizes, it wasn't entirely clear what 100% percent means. With a bit of searching, the help says "it's the page text area", which in practice means the page size, excluding the margins.

And that's where the problem lies: in many cases (importing foreign formats, cover page of a document, etc.) you want to have a textframe which is 100% wide, compared to the full page size, including margins. It was already possible previously to work this around by manually specifying the same size what was used for page size, but that's ugly, you duplicate the setting at two places.

As you can see on the above screenshot, in LibreOffice 4.3, I now implemented this as a new option, you can choose what 100% means for both width and height. File filters are also updated accordingly: in case of ODF an extension is proposed, and also DOCX and RTF filters are updated, where the file format already supported this feature.

For the curious ones, the feature is in master for almost two months now, but I only implemented my favorite part -- RTF filter -- only last week, that's the "news" here. ;-)

If you want to try these out yourself, get a daily build and play with it! If something goes wrong, report it to us in the Bugzilla, so we can try fix it before 4.3 gets branched off. Last, but not at least, thanks for CloudOn for funding this improvement! :-)

I'm sure in this case a few words are worth more than the above picture, so let me describe what you see above. :-)

In case of opening an ODT, DOC or RTF document in LibreOffice Writer, you already got some feedback on where the importer is, in case the process needed more time than what you feel "instant". However, this wasn't supported for DOCX. According to git blame, I added this to my todo on 2012-10-29, and a few months later also a bugreport was opened, requesting the same, but up to yesterday, nothing changed. However, now I've implemented this on master, it'll be part of the 4.3 release.

Back to where I started, what you actually see there is when LibreOffice is in the middle of the import process of the Holy Bible in DOCX format, which takes around 12 seconds on my machine. One could say that speed up quite acceptable for that amount of data, but with a progressbar, it's definitely better. ;-)

Last year in September we decided to get rid of the writerfilter-based DOC tokenizer, and I volunteered to actually do this. As cleanups in general have a low priority, I only progressed with this slowly, though yesterday I completed it, that's why I'm writing this post. :-)

Some background: the writerfilter module is responsible for RTF and DOCX import in Writer. As the above picture shows, the currently used DOC import is independent from it, and there was also an other DOC import filter, that was in writerfilter which was disabled at runtime. As I don't like duplication, I examined the state of the two filters, and the linked minutes mail details how we decided that the old filter will stay, and we'll get rid of the writerfilter one. It's just a matter of deleting that code, right? :-) That's what I thought first. But then I had to realize that the architecture of writerfilter is a bit more complex:

It has the following components:

• the dmapper (domain mapper), that handles all the nasty complexities of mapping Word concepts to Writer concepts (think of e.g. sections ↔ page styles)
• one tokenizer for each (RTF, DOCX, DOC) format

The traffic between the tokenizers and dmapper is called tokens. Naturally it's not enough that tokenizers send and dmapper receives these tokens, they should be defined somewhere as well. And that's where I realized this work will take a bit more time: instead of having a single token definition, actually the ooxml tokenizer defined its own grammar, and doctok also defined two additional grammars. And of course dmapper had to handle all of that. ;-) Given that OOXML is a superset of the DOC/RTF format, it makes sense to just use the ooxml grammar, and get rid of the other two.

Especially that -- by now you probably found this out -- if I wanted to kill doctok, I had to kill the sprm and rtf grammars as well. Otherwise just removing doctok would break the RTF and DOCX import as well, as those also used the rtf/sprm grammars.

So at the end, the cleaned up architecture now looks like this:

And that has multiple advantages:

• It removes quite some code: In libreoffice-4-1, the doctok was 78849 (!) lines of code (well, part of that was XML data, and some scripts generated C++ code from that).
• dmapper now doesn't have to handle the rtf and sprm grammars anymore, so now there is a single place in dmapper that handles e.g. the italic character property.
• Smaller writerfilter binary for the end user: even if doctok wasn't enabled at runtime, it was shipped in the installation set.
• Hopefully it's now a bit more easy to understand writerfilter: at least e.g. if you want to look up the place where dmapper handles the character bold ("b") XML tag of OOXML, you don't have to know that the binary DOC equivalent of that is sprmCFBold, just because we have an unused DOC tokenizer there as well. :-)
• Given that DOC and RTF formats are a dead end, I think it's a good thing that in writerfilter now the grammar is OOXML (that keeps introducing new features), rather than some dead format. ;-)

If you ever tried to use nested comments in Writer (make a selection, Insert -> Comment, then make an overlapping selection, and do it again), you may have noticed that only the ODF filter can load and save such a document properly. Recently I have improved this situation a lot. Motivated by seeing this is now supported in the DOCX import filter, I now added support for this also to the DOCX export, RTF import/export and binary DOC import/export filters.

If you want to try this out, core.git has a ODT and DOC samples to play with.

I've arrived home yesterday from Brussels where I presented at FOSDEM 2014, in the Open document editors devroom.

We also had a Hackfest, kindly hosted by Betacowork on Monday and Tuesday.

Here are a few talks I enjoyed, not counting the LibreOffice ones:

• Simplifying reuse with metadata support in ODF and plugin APIs -- finally a simple way to copy&paste images from Firefox to LibreOffice with source attribution.
• Combining the power of Valgrind and GDB -- useful to know about this possibility
• Two uses cases for the clang C++ parser: Online Code Browser and Qt moc Replacement. -- maybe the first could replace our crappy Java-based opengrok? We'll see.

I was also happy to meet Jacobo, Matus, Tim and Tomaž finally personally. :-)

Quite some other slides are now available on Planet, don't miss them. I also took some pictures, available here, including photos of all speakers in our devroom.

Although LibreOffice 4.2.0 is not yet released, it was already branched off from master in November last year, and improvements for the next release are already cooking in master. One of these will be a major improvement of shape handling in the DOCX import/export filter.

Some background: when DOCX was initially introduced, it still used VML (which is in short an XML equivalent of the binary shape format), and only Word 2010 started to write shapes using drawingML. Given that Word still understands VML, it wasn't urgent for us to write shapes using the drawingML markup. As for import, Word still writes an approximate version of the shape in VML as a fallback -- that's what we read till now. Needless to say, newer drawingML features have no VML equivalent so with time it became more and more important for us to finally read and write shapes in DOCX using drawingML, which just happened in Writer.

I'm posting here a few screenshots showing the improvements I've implemented. Note that final 4.3 is still far from being released, so this is not a complete list. :-) In each case I'm providing a screenshot showing how it looked (at the end of an import/export/import again roundtrip) before, how it looks now in 4.3 and the reference layout. Click on the images to get a larger image:

• document with different colors (test doc):

OK, this has four pictures: before, now, Word 2007 and Word2010. As you can see now we're now on par with Word 2010. ;-)

• document with textboxes inside a group shape (test doc):

• document with textbox, having a special RelOrientation (test doc):

• document with a shape having a custom adjustment (test doc):

• document with different colors (test doc):

If you want to try these out yourself, get a daily build and play with it! If something goes wrong, report it to us in the Bugzilla, so we can try fix it before 4.3 gets branched off. Last, but not at least, thanks for CloudOn for funding these improvements! :-)