This tutorial is a quick introduction to the setup and work with git and gitorious.org in Marble's Google Summer of Code (GSOC) projects. Further details can be found in the links listed in the last section of the page.
The Marble source code is stored in the official KDE Subversion repository. The directory trunk/KDE/kdeedu/marble/ keeps the latest development changes. This is the reference code you should work with during GSOC. For your convenience this repository part is mirrored at gitorious.org in the svn.kde.org branch of the marble repository in the marble project. This branch is updated from time to time to keep in sync with the development in Subversion.
For your GSOC project, you setup another git repository on gitorious.org: Your personal clone of the marble gitorious repository. You will be the only person writing to the repository. Additionally you can synchronize it with (import) the latest Subversion changes at your convenience. There's a fourth repository, your local clone of your personal gitorious clone. Local means that unlike the other repositories, this one is only stored on your system. This is the repository you work with most of the time. The others are only for synchronization.
Summing it up, there are four physical repositories:
Logically, there are only two repositories:
To understand how these repositories are updated / synchronized, let's have a look at who does which changes. First, changes from the top:
Changes from bottom to top happen like this:
Now how does your GSOC project end in the official Subversion repository? This will be handled at the end of GSOC via reviewboard. Git can create the necessary patch easily.
While the number of repositories involved may seem huge and the process very complex, it is easy and fast to work with in practice. The main advantage of git in the GSOC context is its ability to handle merges easily. Merges occur when you synchronize your personal clone with the Marble development sources and when your GSOC project is merged ino the Marble development sources at the end of GSOC.
Setting up your personal clone of the marble/marble repository in gitorious is quite easy.