Skiing with Maemo Mapper and Google Earth

Last weekend, we were skiing for three days, and I took the N810 with me to do some GPS tracking. Back home, I wanted to visualize the route that we took, so I saved the track as .gpx file in Maemo Mapper, copied it over to my laptop and loaded it into Google Earth:

The result is quite impressive. Although there are some tracks missing, one can get the idea which slope we were going down most often. Sadly, Google Earth's satellite maps for this specific area do not show any snow, so the pictures look a bit weird. A nice use case for the tablets - thanks to Maemo Mapper!

gPodder 0.15.0 now in Maemo Extras

The latest release of gPodder, a podcast downloader for Maemo has been released today, and packages for it are already available in Maemo Extras for Chinook, Diablo and Fremantle Alpha (..but there is no Extras-Promoter for Fremantle yet?).

Highlights of this release:

• Download resuming between sessions
• Finger-friendly lists using libmokoui2
• Friendly folder and file names for downloaded files
• Finger gestures for the episode list

The finger gestures are very nice and can be used to show episode details or play back episodes. Enable the configuration option maemo_enable_gestures and then swipe left to display shownotes or swipe right over an episode to listen to it.

Get it from Maemo Extras.

Screenshots of gPodder in Fremantle Alpha SDK

As we all know, the Fremantle Alpha SDK has been released, and it features (at least parts of) the new UI. I downloaded the SDK and tried running gPodder inside it, and wanted to show you some pictures so you get an idea how an unmodified Maemo 4 UI looks on Fremantle:

Some other remarks: It seems that images have inverted color. I don't know if this is just a bug or if it's intended to be. Also, Xephyr sometimes crashes, which seems to be related to Clutter, although I do not really know ;) I expecially like how they managed to move the buttons of GTK Dialogs to the right side and stack them. This is a very good decision for the widescreen display, and it also means that one dialog in gPodder fits the screen nicely in Fremantle now that did not (and still does not - my fault ;) on Maemo 4.

See all screenshots at gPodder on Fremantle Alpha SDK on Flickr

Optimizing Tennix for Maemo

As I promised some weeks ago, here are the results of our take on optimizing a SDL game (Tennix) for the Maemo devices. All other platforms on which Tennix runs obviously also profit from these optimizations. The presentation with all the details is available here: Optimizing an open source game for mobile devices (PDF). I also have two videos for you: Tennix running on a tablet before and after the optimizations.

Conclusions: Do profile (using oprofile or gprof) your applications to find bottlenecks. Look at callgraphs (using graphviz) to determine function usage. Most of the time, small code changes result in big performance boosts. Some Maemo-specific hints for SDL development are available in Game development in the Maemo Wiki.

The optimized release of Tennix (0.7.0) is available in Maemo Extras already. Go get it! :)

gPodder 0.14.1 in Maemo Extras

Packages for gPodder 0.14.1 (a podcast downloader for Maemo and Linux Desktops) are now available in Maemo Extras (Chinook at least.. the Diablo autobuilder is busy (broken?) at the moment). The UI experiments (mokoui2 finger scrolling) are not included in this release yet, but will be in a future release. 0.14.1 is a bugfix release, so it's recommended that you upgrade.

Quim Gil interviewed on FLOSS Weekly

For all of you who are subscribed to FLOSS Weekly with gPodder, you might have already noticed it: On Saturday, the long-awaited interview with Quim Gil from Nokia has been published. You can grab it from here as MP3 file directly or (even better ;) download gPodder from Maemo Extras and subscribe to FLOSS Weekly.

Optimizing the code of a SDL game

Maybe you have tried it already: Tennix has been available for Maemo for quite some time now. The current version still has room for improvement (performance-wise), and the gameplay part runs a bit slow. That's why our team uses it as an optimization target for a course at the uni until the end of January.

Two benefits: You get a playable, fast tennis game for your tablets, and we get a bit more proficient in writing more efficient code and making better use of the current hardware. This will obviously also benefit the Desktop version of Tennix, as both use the same codebase.

I hope to be able to draw some conclusions and give you an overview of what we were able to do in a few weeks. Until now, try out Tennix and get used to its (relatively slow) speed, so that you feel the improvements when the optimized release is out :)