Digikam/CodingSprint2014

KDE Graphics Coding Sprint 2014

The KDE Graphics coding sprint 2014 will take place at Berlin, Germany, from november 14h to 16th 2014.

KDE Framework Port

Branches Creation

All port code must be stored in dedicated "frameworks" git branch for each project. Branch must be created from master.

$>git checkout master
$>git pull -rebase
$>git checkout -b frameworks
$>git push origin frameworks:frameworks
$>git branch -a
* frameworks
  master
  remotes/origin/HEAD -> origin/master
  remotes/origin/frameworks
  remotes/origin/master

KF5 Repositories list is given below :

• Libkexiv2
• Libkdcraw
• Libkipi
• Libkface
• Libkgeomap
• digiKam Software Compilation
• Kipi-plugins
• digiKam

KF5/Qt5 Status

Component	Cmake port	pure Qt5 port	pure KF5 port	compile	warnings	Who	Remarks
libkexiv2/src	done	uncomplete	done	yes	yes	Gilles, Laurent	C++ auto_ptr warnings from Exiv2 API. QT_NO_CAST_ASCII removed from build.
libkexiv2/tests	done	uncomplete	done	yes	no	Gilles, Laurent
libkdcraw/src	done	uncomplete	uncomplete	yes	yes	Gilles, Laurent, Veaceslav	C++ auto_ptr warnings from Libraw API. ThreadWeaver and Solid dependencies removed. RActionThreadBase is ported to QThreadPool + QRunnable API instead ThreadWeaver. In second time, KIntNumInput and KDoubleNumInput are deprecated, and we can plan to use Krita Int and Double input widgets to replace RNumInput and add reset button. See bug #284216 for details.
libkdcraw/tests	done	uncomplete	uncomplete	yes	no	Gilles, Laurent, Veaceslav
libkipi/src	done	uncomplete	uncomplete	yes	yes	Gilles, Laurent, Mohamed	libkipi/version.h file renamed as libkipi_config.h to host only SO version ID shared with kipi plugins. core compile with warnings.
libkipi/test	done	uncomplete	uncomplete	yes	yes	Gilles, Laurent, Mohamed	moc header must be placed at end of plugin implementation. see plugin_helloworld.cpp for details.
libkface/src	done	uncomplete	uncomplete	yes	yes	Gilles, Laurent, Teemu	It still warnings about KGlobal::dirs() which must be ported to QStandardPaths.
libkface/tests	done	under process	under process	yes	no	Gilles, Laurent, Teemu
libkgeomap/src	done	uncomplete	done	yes	no	Gilles, Laurent, Teemu	Needs Marble code from kde-frameworks-5 git branch to compile. We need to detect the Marble version somehow, to avoid linking KF5 build against Qt4 version of Marble. Ideas? QT_NO_CAST_ASCII removed from build.
libkgeomap/tests	done	uncomplete	done	yes	no	Gilles, Laurent, Teemu
libkgeomap/calibrator	done	uncomplete	done	yes	no	Gilles, Laurent, Teemu
libkgeomap/demo	done	uncomplete	done	yes	no	Gilles, Laurent, Teemu	Needs libkexiv2 from KF5 to compile.
digiKam Software Compilation	done	not applicable	not applicable	not applicable	not applicable	Gilles	2 new Cmake options have been add to enable/disable digiKam core and Kipi-plugins compilation (disabled by default for the moment). List of checkout repositories managed by "download-repos" scripts is reduced to current sub projects already ready to support KF5. "frameworks" branches are automatically switched. See ".gitslaves" for details. Needs to implement a new way to pass to local shared libs (libkipi, likdcraw, libkface, libkgeomap, etc) the fact that compilation is done under SC, to reduce files to install on the system (as headers files) Needs to find a way to pass to Kipi-plugins and digiKam an information about to find shared libs compiled locally under SC (libkipi, likdcraw, libkface, libkgeomap, etc) and to ignore system based libs.
Kipi-plugins	todo	todo	todo
digiKam	todo	todo	todo

Recommendations

Porting to KF5 is divided in 3 stages:

1/ Change Cmake files. some Laurent scripts do this stuff. We use now ECM scripts collection from KDE core to manage dependencies and report on the console. Some macros disappear, and are replaced by new ones. For this job, it's recommended to look well all done in Cmake files from libkexiv2 and libkdcraw already ported and polished.

2/ Port c++ code using KDE4Support. This include older classes from Qt4 and KDE4 to make transition faster. This will help to have quickly a code compilable, but this will generate a lots of deprecated warnings. First regression tests must be done at this stage to see if nothing is broken.

3/ Port c++ code to pure Qt5. The goal of KF5 is to reduce KDELibs fingerprint everywhere, when it's possible. Qt API will be used in priority against KF5 API. But sometime, this will be not possible as well, without big changes. A lot of KDE API have migrated to Qt5 (as for ex : KUrl -> QUrl and kDebug ->qDebug). It's sound like KDELibs will become an incubator for new implementations which will move later to Qt. Also, to have the most of code using pure Qt5 will simplify future transitions more easy to do.

Common changes to port code

• Not yet ported code sections must be commented or wrapped to #ifdef 0 ... #endif, with compiler warnings printed on the console using #pragma message "Port to ...".
• Change all #include "foo.moc" as #include "foo.h" to prevent compilation errors with Qt5. Qt will generate moc_foo.h files instead. Header file of a class declaration must be placed on top of included header files list from implementation file.
• KF5 plugin factory needs moc header file included at end of plugin implementation to prevent broken linking.
• Debug spaces are now wrapped by qCDebug()/qCWarning()/qCCritical(). New foo_debug.h/.cpp files must be created to declare debug space. See libkface port branch as example. foo_debug.h is not shared, so for shared a library, this header must be only placed as private in implemeentation files, not header files.
• "KDE4_BUILD_TESTS=ON" cmake flag is replaced by "BUILD_TESTING=ON" to build tests sub-dir.
• "CMAKE_BUILD_TYPE=debugfull" cmake flag is replaced by "CMAKE_BUILD_TYPE=debug" to build code with debug symbols.

Link to documentation to port code

• KF5 port

• Qt5 port

• ECM - Extra CMake Module

• ECM - Documentation

Scripts to port code

Laurent Montel has written scripts to port CMake and C++ code to KF5/Qt5 and remove kdelibs4support dependency. There are available in this repository.

Scripts must be applied in this order, with a test compilation between each one :

• Full safe scripts :
  • convert-to-k4aboutdata.pl (first one to apply, this help to compile)
  • adapt_cmakelists_file.pl (to convert CMake scripts, but code must don't be capititalized)
  • remove-kde4support.pl
  • convert-kicon.pl
  • convert-kmenu.pl
  • convert-kshortcut.pl
  • convert-kcolordialog.pl
  • convert-klistwidget.pl
  • convert-kmd5.pl
  • convert-kmenubar.pl
  • convert-ksplashscreen.pl
  • convert-kdebug.pl

• Less safe scripts :
  • convert-kintnuminput.pl
  • convert-kintspinbox.pl
  • convert-ktextbrowser.pl
  • convert-kfontcombobox.pl

• Scripts which need to check in-deep all changes :
  • convert-kvbox.pl
  • convert-kdialog.pl
  • convert-kcmdlineargs.pl
  • convert-kdebug-with-argument.sh (this one change kDebug(1556) en qCDebug with some info after to convert)
  • convert-kmimetype.pl

• Last scripts to apply :
  • clean-forward-declaration.sh (remove forward declaration, to do when all compile fine)
  • clean-includes.sh (try to remove not used includes, not safe to 100%)
  • port_to_autogenerate_export_header.sh (convert to new signal/slot API, not safe to 100%)

Image Editor Model/View Fixes and Finalization

CANVAS : full image dimensions not shown when not viewing at 100% zoom level

CANVAS : image shifts position in mouse-over mode when changing between Before and After

CANVAS : mouse-over preview mode does not work

CANVAS : unable to zoom out to less than fit to window

Unable to crop due to image corruption into canvas with not X11 based computers

Coding Sprint Notes

Next major task is to port digiKam to Qt5. Approx. 10% is already ported by Gilles. Objectives for this coding sprint:

• Specify timeline for porting digiKam
• Identify priorities (what should be ported first)
• Delegate porting tasks to developers (who does what)

Shourya Singh Gupta works on implementing the Kipi tools functionality in the Batch Queue Manager (Tools Settings).

Marcel Wiesweg works on memory consumption in database and the bug with JPEG (and RAW) image preview on high-resolution screens. Also see https://bugs.kde.org/show_bug.cgi?id=205776

He work also to complete the Removable collection support. The goal is to show thumbnails from disconnected media, but not editable as well. A feedback to the user is provided to indicate that items and collection are not available, but users can continue to search and preview collection through database. See bugs https://bugs.kde.org/show_bug.cgi?id=191494 and https://bugs.kde.org/show_bug.cgi?id=114539.

MySQL support is now disabled by default because it's not fully functional and still experimental. MySQL support still fully available of course, but as an optional feature.

Gilles has polished whole libkgeomap public API to be ready for KF5 port. A lots of changes have been applied to reduce binary compatibility issues, especially, if library will be moved somewhere in KDE core to be more easily used by another project as KPhotoAlbum, like it have been done recently about libkface.