[Qgis-developer] Legend refactoring branch merged

[Martin Dobias]

Hi everyone

I have just merged the first part of the legend refactoring work to
master [1]. It does not really bring any new features for the end
user, the changes are mainly under the hood. Things should ideally
work as before, if not then probably it is a bug.

There will be second part of the work related mainly around improved
layer symbology display in legend, more interactive legend and more
options for customization. At Lutra Consulting we are still looking
for funders willing to co-fund the work. At this point let me thank
SIGE and Swiss QGIS User Group for supporting the project.

Please test thoroughly - the legend has received quite a lot of
features over time, so there could be still some minor features I have
missed to port to new implementation.

The format of the project file has changed, but there is backward
compatibility with older projects which should allow seamless
transition. Once saved with 2.4, the older versions of QGIS will loose
the information about grouping.

If you are interested in studying the new code, there are two new
folders of interest:
- src/core/layertree
- src/gui/layertree
There is basic doxygen documentation for the new core classes, I plan
to add more, add python bindings and unit tests.

Regards
Martin

[1] https://github.com/qgis/QGIS/commit/b2a4c765b4e8a3fa00385a56a358952f46a1957a