[Qgis-developer] multi-view

Martin Dobias wonder.sk at gmail.com
Wed Jan 19 13:56:38 EST 2011

On Thu, Jan 13, 2011 at 2:16 PM, Massimo Di Stefano
<massimodisasha at yahoo.it> wrote:
> Hi All,
> multiview is nice and remember me the addtab capabilities
> (that's an other way to have multiview,
> the tab are detachable and mouse over on the relative tab show a canvas
> preview)
> so, i hope the multiview work will not forget as :
> http://trac.osgeo.org/qgis/ticket/1622
> lynxID and me worked hard to develop and test it,
> AddTabb patch was needed to start to develop the planet plug-in.
> The patch was never applied due to main api change ?

Hi Massimo

the patch for tabbed interface has a lot of consequences. First of all
it is important to answer what are the use cases for multiple canvases
- what are pros and cons of such interface for both users and
developers. For example, to what degree the individual map canvases
should interact between each other - allow different sets of layers,
allow different symbolization of layers, different projections,
simultaneous editing of one layer in various canvases? From
developer's point of view there are also many questions - should map
canvases share the instances of layers or create duplicates, should a
map tool be bound to one map canvas or handle all existing canvases?

As you probably see, for a different set of use cases the answers
would be different. The patch itself is long and doesn't come with any
overview of the architecture. I would recommend you to start a RFC
which can be discussed and modified to reach the consensus. Anyway a
change like this looks to be more suitable for qgis 2.0 where we will
be able to break API and thus implement things well.

I have the same feelings for the split view modifications. First it's
better to share and talk about the concept of bigger features in order
to have clear way into trunk later.


More information about the Qgis-developer mailing list