Create a diff document.

Hi,

I'm working on a backup and version service, using btrfs, sqlite and
fuse to provide easy access to backup and previous versions.

Now I'm building a qt viewer to show the differences between a
previous version of a document and the current one (or another
version). For office documents there is no such call (yet?) in the
lokit api.

I can get a long way by:

- save the documents as fodt on a temp location.
- compare them using diff

too bad the result does not have the format of a normal fodt document.

Is there another way to create the diff of two office documents which
is viewable using lokit?

Stef Bon