Open Malaysia

To answer your question about SpreadsheetML VML, it's referenced in section 6.4 (page 4920), and is pretty much a copy/paste of section 8.6.2 that you have reprinted above.

But in fact, there is no specs-wide list of where VML appears, especially in NEW files. For instance, VML is also used if you insert a new OLE object.

There is a reason why Microsoft does not document this stuff. They would have to give the documentation of OLE, which in turn would show clearly as in water that this stuff is platform-dependent : Windows.

That Microsoft goes as far as not even listing where VML is used, is also probably because it brings back a taboo subject. Which I'll address right now.

Back in 1998, Mr Gates and his crownies had bet on WYSIWYG HTML. That's how they convinced themselves that they had finally taken the internet train. Of course, when Windows 98 shipped, it was with Internet Explorer bundled with the operating system. So with that in hands, Microsoft planned to make sure that this OS browser coupling would never end. To that end, they made sure the Office team would create a dependency on it. Office already had created a dependency on Windows (binary formats, OLE, ...) but apparently making a productivity app depend on an OS was not enough for them, they chose to also make sure that Office would become a recruitment tool for Internet Explorer, and vice versa.

Hence, one of the BillG's memo whose copy you'll find here : http://antitrust.slated.org/www.iowaconsumercase.org/011607/2000/PX02991.pdf

As amazing as it reads by itself, with BillG making it very clear that Office implementing open standards was a mistake and that it would cause the death of Windows (i.e. the dependency as mentioned above), he mentions what we might want to call a new trojan horse, using Internet Explorer to view Office documents (Word, Excel, Powerpoint) with only a web browser. In other words the WYSIWYG HTML thing.

How does this memo relate to the discussion about VML?
Well, it's very simple, in the entire history of the Office product group, only once did they work with the Internet Explorer team. And that was to implant what is now known as the VML library. The VML library is surfaced as a proprietary markup whose semantics is not documented and is a direct XML serialization of the shared drawing library in Office, internally known as MSO (codename Escher).

So the use of VML inside Internet Explorer was the trojan horse which would ensure that Office documents shared on the web would only render on Windows. There is no VML implementation out there other than Internet Explorer's. And again, there is Microsoft IP in it, so that's probably a reason why.

That was the days of Office 2000, XP, 2003 and 2007. In Office 2007, the Office team wanted to move to another markup language for their graphics layer. Not because of all a sudden, they wanted to remove a dependency on the OS and Internet Explorer, it's because they wanted to add new features and create yet another dependency. In Office 2007, DrawingML is used to describe a couple of 3D effects such as bevel and so on. The semantics and actual layout algorithms are not documented at all. They are extensively used in the new chart drawing engine for instance. And, as a result, since the old chart drawing engine, and the old shared MSO are gone with it, it means that opening an existing file that contains a chart will be rendered differently in Office 2007 than in older Office versions. For instance, if you create an Excel 2000 file with a chart, and open that file in Excel 2007, you'll see something different. So much for "100% backwards compatibility"...

Last but not least, since the Office team could not, or did not want to, make a full move to DrawingML in Office 2007, there are bits of VML all over the place, be it in NEW Word 2007 files, NEW Excel 2007 files and NEW Powerpoint 2007 files. This comes in contradiction with the specs proposed for ISO standard, and in practice this also puts a great barrier to entry : it requires a consuming application to support VML if said application wants to render it.
Of course, said application in some cases may simply ignore the VML parts, but then if your application is supposed to render for example an Excel spreadsheet containing a comment on it, and ignores VML, then customers will see it as a bug! and it turns a black eye to a non-Microsoft application in favor of Microsoft Office applications. This technique is nothing other than lock-in. They are making sure the barrier to entry is very high for applications willing to be rich consumers of those files, and in practice it means Office itself is always better than anybody else. Again, this contradicts the specs. An international standard is supposed to provide fair and equal footing to everyone implementing it.

So the Office team at Microsoft could not manage to get rid of VML. It is possible, unless they intentionally use it as a lock-in tool, that next version of Office, codenamed Office 14, will be the first one to have an Office-wide DrawingML implementation. Until then, Office 2007 is at odds with the specs that Microsoft is pushing and as a result, it is not a reference implementation of the specs!
In other words, since there cannot be a non-Microsoft implementation of the specs (it will take at least ten years for a company starting now, and it will never achieve 100% fidelity since many things are missing in the specs), it follows that there is simply NO reference implementation out there! Quite amazing...

One only hopes that, in the meantime Microsoft won't change their mind again, and that they not only will keep VML for the foreseeable future, but also will create a new dependency to a Windows-only API. The new graphics .NET 3.0 based API called Windows Presentation Foundation comes to mind, obviously...

We'll see.

In MS-ECMA-OOXML Part 4 "Mark-up language reference" there are a lot of references to "DiagramML". Example:

5.9.3.5 pt (Point)
This element defines a point in DiagramML. A point in DiagramML is defined to hold data associated with a particular point or node in a diagram."

I didn't hear about it. It is just another internal format of Microsoft to be super-fast-tracked by ISO together with DrawingML, MathML, VML, OPC, etc, etc?

"Word was only able to do the work to upgrade to the new DrawingML framework for Charts; Smart Art; and Pictures. All other drawings still use the legacy VML architecture. That's why we needed to include both VML and DrawingML in the standard; otherwise folks wouldn't have been able to fully interop. The hope of course is to move to use DrawingML for everything in future versions, as Excel and PowerPoint did."

http://blogs.msdn.com/brian_jones/archive/2006/10/09/Office-Open-XML-final-draft_210021002100_.php