Language Selection

English French German Italian Portuguese Spanish

Marble's Secrets Part I: Behind the Scenes of Marble...

Filed under
Software

If you've ever followed KDE 4 development then you've probably heard about Marble. Marble is a virtual globe which displays the earth. So Marble can be used as a nice digital replacement for your desktop globe at home where you can look up places.

But wait! There's more to it: Actually these days Marble can also display flat maps (thanks to Carlos Licea), can show different "map themes" and can serve as a Qt4-widget as well as an application! This means that as a programmer you can use Marble in your very own project as a map widget (License: LGPL). Marble was designed to run on any device and on any operating system supported by Qt4 without any further requirements. You can download the latest version of Marble together with KDE 4.0.1 here (It's part of the KDE-EDU module).

How Marble stores texture data

If you start Marble you might realize that the startup time is pretty good: It usually takes maybe 2-5 secs to start Marble (and we are working on improving that dramatically). If you zoom into the earth you might notice that Marble doesn't get slower while zooming in. Looking at the amount of memory being used up you will also see that memory numbers don't change either. No matter how much you zoom in it's as little as 65-100MB which is pretty lean compared to other virtual globes.

Among other concepts this is being accomplished by loading the map piece by piece. Marble uses a concept that is very popular among virtual globes: Quadtiles. In fact we are using the most simple form of Quadtiles compared to other more sophisticated solutions. We decided to do so for reasons of pragmatism and in order to keep things easy to understand for people who want to contribute to Marble.

More Here




More in Tux Machines

Open source is in our DNA

The same thing that compels us to make Linux (and many other projects) free and open source is present in many of humanity's greatest achievements Read more

Debian Is Dropping Support for VLC Media Player, Mediawiki for Wheezy LTS

The Debian Long Term Support (LTS) developers have announced that they are dropping support for certain packages as part of the extended life cycle for the Debian GNU/Linux 7 "Wheezy" operating system. Read more

Hands on: What's new and noteworthy with Android N

With Google's I/O developers' conference behind us, it's time to start looking forward to what's next in the world of Android. The most prominent thing is Google's rapidly approaching Android release, currently known only as Android "N." (The company has yet to reveal the full name or version number.) While the software itself isn't expected to arrive until sometime this summer, we're getting an increasingly clear picture of the fresh features and improvements it'll provide. Read more

today's leftovers

  • FLOSS Weekly 389: Best Practices Badge
  • OpenGL 4.5 For The Intel Mesa Driver May Be Imminent
    Intel has been rapidly advancing their OpenGL 4.x support and OpenGL 4.5 is even in sight now. Kristian Høgsberg today landed GL_KHR_robustness support in the i965 DRI driver, a requirement for OpenGL 4.5.
  • Shotwell vs. digiKam
    How to manage your photos? – That is probably the biggest question for anyone doing anything with a photo camera. As resolutions of cameras grow, the data we have to manage is growing ever. In my case I am talking about more than 50000 photos and videos measuring up to about 200Gb of disk space, constantly growing. There are several photo management softwares out there, I guess the most commonly used ones are Shotwell for the Gnome desktop, digiKam for the KDE world, and FotoXX. I have not used Shotwell and digiKam for quite some time, and collect here my experiences of strength and weaknesses of the two programs. FotoXX seems to be very powerful, too, but I haven’t tested it till now.
  • Tweet your database with db2twitter
    db2twitter is developed by and run for LinuxJobs.fr, the job board of th french-speaking Free Software and Opensource community.
  • Tiny Core Linux 7.1 Screenshot Tour
  • Annoying myths about Linux that won't go away
    Linux has been around for many years, and has gotten better and better as time has gone by. Yet there are some enduring, inaccurate, and annoying myths about Linux that persist to this day. A Linux redditor started a thread about Linux myths and got some interesting responses from his fellow Linux users:
  • GStreamer Spring Hackfest 2016
    After missing the last few GStreamer hackfests I finally managed to attend this time. It was held in Thessaloniki, Greece’s second largest city. The city is located by the sea side and the entire hackfest and related activities were either directly by the sea or just a couple blocks away.
  • My talk at OSDC 2016: Continuous Integration in Data Centers – Further 3 Years Later
  • Isenkram with PackageKit support - new version 0.23 available in Debian unstable
    The isenkram system is a user-focused solution in Debian for handling hardware related packages. The idea is to have a database of mappings between hardware and packages, and pop up a dialog suggesting for the user to install the packages to use a given hardware dongle. Some use cases are when you insert a Yubikey, it proposes to install the software needed to control it; when you insert a braille reader list it proposes to install the packages needed to send text to the reader; and when you insert a ColorHug screen calibrator it suggests to install the driver for it. The system work well, and even have a few command line tools to install firmware packages and packages for the hardware already in the machine (as opposed to hotpluggable hardware).