[Marble-devel] Questions About Marble Installation

Fri Apr 23 10:23:05 CEST 2010

Hi Paul.

On Thursday 22 April 2010 21:27:54 Paul Carlisle wrote:
> We've hit one small snag. We are building on Solaris 10 using the native
> compiler, and there are known issues building Qt's WebKit module. 

Ah. We didn't know this. 
The only place that QWebKit gets used with is our "TinyWebBrowser" class.
We had an alternative implementation that was based on QTextBrowser instead of 
QWebkit.

I think the commit which threw out the old QTextBrowser implementation was this 
one (or one of the earlier commits that you can see when doing "svn log 
marble/src/lib/TinyWebBrowser.h": 

r968507 | ewoerner | 2009-05-15 23:38:58 +0200 (Fr, 15. Mai 2009) | 2 lines

"Throw pre-Qt-4.5 code out"

If you check the diff then you might be able to replace the current QWebKit 
implementation with the old QTextBrowser one.

> It doesn't look like it will be too hard for us to eliminate the affected
> code from the Marble build, although we will try getting WebKit to build a
> couple more times before taking that route.

It shouldn't be too hard. Indeed we really should have a

#ifndef QT_NO_WEBKIT
//QtWebKit specific code here.
#endif

in our code. We do the same with QT_NO_PRINTER already (see the code inside 
marble/src/QtMainWindow.cpp). Whatever solution you come up with, could you send 
us a patch? :-)

> I don't suppose there's a handy compiler switch we could define that would
> produce a build with these features turned off?

Not yet (that "switch" would naturally be Qt's own define QT_NO_WEBKIT).
But we'd be grateful for a patch. :-)

Torsten

> On Thursday 22 April 2010 03:42:03 Torsten Rahn wrote:
> > Hi Paul,
> > 
> > On Wednesday 21 April 2010 23:34:41 Paul Carlisle wrote:
> > > We will very likely be using Marble for an upcoming project that
> > > requires the display of a user's position on a map. Resolution will
> > > never have to be very high - at the finest, we probably won't have to
> > > show an area any smaller than roughly 50 miles on a side. The
> > > application will be written in C++ using Qt and the MarbleWidget
> > > class, running under Unix.
> > 
> > Great :-)
> > 
> > > Unfortunately, this application will almost never have Internet access,
> > > so we will be forced to provide a large image, or our own set of image
> > > tiles.
> > 
> > Yes, that would both be possible.
> > 
> > > After playing with a simple demo program, I note that the Blue Marble
> > > dataset only seems to contain a single JPEG image that is 2700x1350
> > > pixels. This seems awfully small for the level of detail seen in the
> > > zooms. Is it drawing the data from somewhere other than the <install
> > > location>/data directory? Or is Marble just using a really good scaling
> > > algorithm?
> > 
> > Marble is fetching more tiles from the internet while you are browsing
> > the
> > 
> >  map. The data is downloaded to ~/.marble/data by default in all versions
> >  up to 0.9.x.
> > 
> > So I guess you have an internet connection running in the background
> > which downloads the data behind your back (it's possible to disable this
> > 
> >  behaviour btw., so that Marble remains in offline mode). :-)
> >  
> > > I note in your documentation that the largest image that the widget
> > > will automatically tile is 10800x5400. If we choose to download, say,
> > > the full- resolution NASA Blue Marble images and provide our own
> > > tiles, is it sufficient to simply place the tile directly tree in the
> > > data area, or are there additional steps needed to make the
> > > application locate the tiles?
> > 
> > There are no further steps necessary. :-) You can just place the
> > downloaded tiles either in the local ( ~/.marble/data ) or
> > system/install directory.
> > 
> > > Also, what is the recommended way of telling Marble where the data is
> > > stored?
> > 
> > Yes, see the third chapter at:
> > http://edu.kde.org/marble/obtain.php
> > 
> > > Is there an environment variable, or can the path be set at
> > > runtime? I'm referring to the widget, not the Marble executable.
> > 
> > Yes, see the third chapter at:
> > http://edu.kde.org/marble/obtain.php
> > 
> > You might also have a look at the documentation of the MarbleDirs class
> > for
> > 
> >  a better understanding :-)
> > 
> > Note also that this stuff has changed in trunk. For development we
> > usually recommend to use the stable Marble version (i.e. right now this
> > is 0.9.x). But if you should decide to use trunk then you need to be
> > aware of the
> > 
> >  recent changes (which Bastian could tell more about).
> >  
> > > We will
> > > likely not be given root access when we install our application and
> > > data, so we need to be able to configure Marble to look where we will
> > > be forced to install.
> > > 
> > > If this project succeeds, we may explore the possibility of building
> > > our own Open Street Map server in order to provide the follow-on level
> > > of detail some users will want.
> > 
> > That should work fine with Marble as well.
> > 
> > > For now, however, high-resolution imagery
> > > will probably be sufficient.
> > 
> > Cool,
> > 
> > Best Regards,
> > 
> > Torsten
> > 
> > > Thank you in advance for your help.
> > > _______________________________________________
> > > Marble-devel mailing list
> > > Marble-devel at kde.org
> > > https://mail.kde.org/mailman/listinfo/marble-devel
> > 
> > _______________________________________________
> > Marble-devel mailing list
> > Marble-devel at kde.org
> > https://mail.kde.org/mailman/listinfo/marble-devel
> 
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