Overview of open issues and things to be done for the ["DebianInstallerGUI"].
See also open [http://bugs.debian.org/cdebconf-gtk-udeb bug reports against cdebconf-gtk-udeb].
There is currently one remaining issue that blocks including the graphical installer from being included in the main installer build infrastructure: udeb dependency resolution.
udeb dependency resolution
During a build, not all dependencies between udebs can be resolved if all udebs are taken from the official mirrors. The current workaround is to copy some udebs to "localudebs", but this is not acceptable for the main build infrastructure (see also [http://lists.debian.org/debian-boot/2005/10/msg00955.html this thread]).
The problem occurs if some udebs depend on a normal library package (libfoo.deb) while other udebs depend on the corresponding udeb (libfoo.udeb).
There are two known solutions for this issue.
- Change dependencies in udebs in such a way that they all depend in the same manner. This is what currently happens for the main installer. Problem with this solution is that the udebs involved are not maintained by the d-i team. Also, this would be ignoring the structural problem.
Fix the toolchain (mainly dpkg-dev) to improve automatic dependency determination when udebs are build. A [http://lists.debian.org/debian-dpkg/2005/06/msg00198.html patch] for this has been proposed but has not yet been implemented.
Frontend crashes when user switches to a different virtual console while the frontend is busy ([http://bugs.debian.org/cgi-bin/bugreport.cgi?bug=339379 #339379]). If the frontend is waiting for input, console switching works.
Option in the main menu to exit to a shell does not work ([http://bugs.debian.org/cgi-bin/bugreport.cgi?bug=339855 #339855]).
The graphical version of the installer is currently available for Intel x86, AMD64 and PowerPC. The PowerPC port probably needs work to get different types of system correctly supported. Other architectures the graphical installer could be ported to include Sparc, Alpha and HPPA.
One of the main advantages of the graphical version of the installer is that it can support languages that use combining characters. We are currently using mainly TTF fonts, with the exception of Japanese and Chinese.
Fontconfig is used for font management. fc-cache files are automatically generated at startup.
The following issues are open with respect to fonts:
- Not all fonts needed for the graphical installer have yet been packaged into udebs (needed for inclusion in the official Etch release).
- Translators should check if their languages are displayed correctly and check for missing characters. Special attention should be given to Indic languages, Arabic and Hebrew. Help from translators may be needed to decide the optimal font for the installer (taking into consideration both quality and space required).
- There are known problems for Indic languages and Arabic. These need to be specified and traced. Possibly extra software is needed for correct display.
- Ideal would be to have each character we need present in only one font. The current fonts have a lot of overlap which wastes space.
- Display has to be good both when no language has yet been selected (language selection screen) and when it has.
- Possibly font configuration can be improved. It would be very nice if we could influence which font is used for a specific language.
Requirements for packaging fonts
- Total amount of space used for fonts should be minimized.
- Only font files that are actually used in the installer should be included.
- Minimize overlap between fonts. Is it possible to "strip" characters from a font?
Overview of fonts currently used
Base characters (Latin) are taken from ttf-freefont (existing udeb).?BRThis font was selected because it looks quite good, has a character set that gives good support for a lot of languages and was already packaged as an udeb. A negative aspect is that it also has partial/limited/ugly support for other scripts/languages and it would be better to only have specialized fonts for those.
For Indic languages we currently include fonts from ttf-devanagari-fonts and ttf-punjabi-fonts (both maintained by Jaldhar H. Vyas <firstname.lastname@example.org>)
- Gargi_1.7.ttf (ttf-devanagari-fonts)
- chandas1-1.ttf (ttf-devanagari-fonts)
- lohit_hi.ttf (ttf-devanagari-fonts)
- Saab.ttf (ttf-punjabi-fonts)
- lohit_pa.ttf (ttf-punjabi-fonts)
For Arabic we currently include fonts from ttf-arabeyes (maintained by Mohammed Elzubeir <email@example.com>)
For Chinese and Japanese we currently use bitmap fonts from xfonts-wqy (maintained by Carlos Z.F. Liu <firstname.lastname@example.org>). Initially we used ttf fonts, but it turns out that bitmap fonts are a lot more readable (and smaller in size).
For Korean we currently include fonts from ttf-unfonts (maintained by Changwoo Ryu <email@example.com>)
Note This is just an initial collection we've put together. There are known issues for some languages and possibly additional fonts are needed. It also is very much possible this is not the optimal mix of fonts for the graphical installer.
Information on how to play around with fonts is included in ["DebianInstallerGUIBuild"].
- Screen resolution.
- Currently fixed at 800x600. Should be made flexible (adapt to resolution set by system or user).
- Interface should adapt itself so that text blocks are never too wide for optimal readability.
- Improve accessability (for the visually handicapped). One way to do this is to support different themes (color schemes). (Note: should not lead to a major increase in initrd size.)
- Progress bar in separate window.
- Alternative (graphical) ways to start a shell or browse log files.
- Interface design.
- Create custom plug-ins for cdebconf to improve handling of some dialogs and make optimal use of possibilities offered by the graphical environment.
Reduce size of initrds
The initrds are currently very large which also results in fairly high memory requirements to run the graphical installer. Size has thus far not been a major concern, our focus has been on getting things working.
Options to reduce initrd size.
- Library reduction for graphical libraries.
- Remove unused files from udebs.
- Reduction of space used by fonts (see above).
Migrate from gtk+-directfb-2.0.9 to gtk+-directfb-2.8.3
The udebs for gtk+-directfb are based on a [http://www.directfb.org/downloads/Libs/gtk+-directfb-2.0.9-2.tar.gz set of sources] released in Apr 2003; it's now possible to build a set of libraries based on gtk+2.8.3 which was released around Oct 2005. The main problem is that [http://wiki.debian.org/DebianInstallerGUIBuild building] is rather tricky, and there are no pre-patched sources available from upstream. Upstream author is now working on [http://lists.freedesktop.org/archives/cairo/2005-November/005625.html including directfb backend into Cairo main line] as a first step; [http://mail.gnome.org/archives/gtk-devel-list/2005-November/msg00057.html inclusion of gdk-directfb code into gtk+ tree] should follow then. Once upstream libraries will be ready to be used, they'll have to be packaged into udebs before we can use them in the installer.