ModRana Roadmap
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Qt GUI
A Qt base is currently the main item on the modRana roadmap, due to multiple reasons:
- it enables modRana to run properly on Harmattan
- it enables the use of kinetic scrolling, smooth animations and generally improves performance
- generally better suitable for touchscreen interfaces with Qt Quick (QML)
- unlike Clutter, that needs OpenGL, QML also supports software rendering
- development experience with Mieru generally shows it's much faster to work with than doing custom UI with Cairo
- removes the dependency on GTK
- it is currently not possible to submit applications with outside dependencies both to the Ovi store and to Apps for MeeGo (AFM seems to be working on dependency support though)
What about the current Cairo + GTK based GUI ?
the new Qt based GUI should be just another alternative together with the GTK one. Also in the process more a clear core-GUI separation should be developed to enable other alternative GUIs (EFL,SDL/PyGame,Clutter/MX,etc.).
Uses for the current GTK GUI
- devices and environment with old versions of Qt
- Neo FreeRunner
- Open Pandora (not sure ?)
- Android chroot (not sure ?)
NOTE: Qt/QML unlike Clutter has a software renderer so OpenGL is not needed to use it. Might be interesting to see the QML vs GTK software rendering performance.
Main drawbacks
- only basic acceleration provided by X
- no 3D acceleration, smooth scrolling, rotation animation acceleration
- as the classic GTK widgets are basically unusable on mobile devices, modRana has to basically build its own GUI toolkit with Cairo
- while flexible, this is very labor intensive
- most of new features and improvements are not blocked by extensive GUI improvements needed to make them usable, the backend work is quite easy in comparison
- examples:
- on-map context menu - needs a new context menu widget
- long list handling with search - kinetic scrolling (is it doable with Cairo) + interactive search box [built in in Qt Components]
- clickable in text links [easy with QML]
- multiline text editing for POI descriptions, etc. [very easy with QML]
What needs to be done to get the Qt GUI in a usable state
Separating the GUI logic to a GUI module
Most of the core GUI logic currently resides in the modRana "kernel" the modrana.py file. This logic needs to be transfered to a separate GUI module tat can be loaded by modRana at startup, either by providing a CLI parameter or automatically (once implemented).
This work will be partially based on Mieru, which already uses the concept of separate GUI modules & has advanced CLI argument support.
What needs to be done ?
- add pluggable GUI module support
- move the current GTK logic to a GTK GUI module
- add proper CLI argument handling
- -d, --device - set device module
- -u, --ui - set which GUI to use
- --lat, --lon, --zoom, --layer - set a given map screen parameters at startup
- --no_gps - don't start GPS on startup
- something else ?
Writing a Qt GUI module
The Qt GUI module
- write a proper