Google Summer of Code 2013

Thanks to everyone who participated in the Google Summer of Code this year!

Andreas posted a summary of the projects and results on the SDL website:

SDL Google Summer of Code 2013SDL gains meta-build and visual-test
capabilities from Google Summer of Code 2013

After a break in 2012, SDL was a member organization in Google Summer of
Code again in 2013. The proposed GSoC projects were guided by the
statement: ‘‘With the SDL 2.0 ABI freeze in place, the general theme this
year is creating a top quality SDL 2.0 release!’’ Early in the year, the
call attracted several students who wanted to hone their coding skills on
several proposed ideas related to our favorite open source multimedia

The SDL maintainers, GSoC org admin and potential GSoC mentors selected
Apoorv Upreti and Ben Henning to work on two projects.

Project Idea #1 Interactive and Visual Test Automation for SDL 2.0 was
geared to further improve the test coverage of SDL by adding a new harness
that could perform graphics-level testing against SDL-based applications
such as testsprite2. This project was mentored by Andreas Schiffler.

Project Idea #2 Multi-platform meta-build system for SDL 2.0 was designed
to alleviate the chore of having to create and maintain the many
cross-platform build artifacts present in SDL by creating a simple,
programmatic meta-build system. This project was mentored by Gabriel Jacobo.

The first of SDL’s 2013 GSOC projects was a visual test harness that
enables validation of a final SDL application at the graphical level build
by Apoorv Upreti. Sam asked for this after running into some interesting
event-behavior bugs in the lead up to the SDL 2.0 release. We had the plan
to create a new test harness that can launch an SDL application process
using any number of parameters, control it via actions such mouse events,
and verify the state and output visually through screenshots. The work was
broken down into 5 themes that build on each other: Design and Core
Infrastructure, Variation of SUT Command-line Options, Action Based Testing
and Core Test, User Interaction Actions, Screenshot Analysis and Visual
Oracle. Using a mini-Scrum process, we broke these themes further down into
over 20 user stories such as “As a SDL tester, I want to be able to run the
harness so that it tries all possible SUT options.” which themselves were
split into individual coding tasks. Needless to say, to build such a system
is a tall order - regardless of process. Apoorv got through most of it and
produced a well documented and usable new harness that can - for example -
launch “testsprite2” with all possible command-line variations to check for
crashes, or validate the rendering system for a set of blend modes against
manually verified “gold standard” images. Unfortunately, the project did
run out of time at the Google mandated “pencil’s down” date and some
features, including the interactive mouse and keyboard actions, were not
fully completed yet. However, since a solid foundation was build by Apoorv,
these additions should be easy to make by him or the community over time.

Apoorv’s code (soon to be merged into mainline SDL) can be found here:

Apoorv’s final blog post has some details on usage:

The second of SDL’s 2013 GSOC projects was a build system developed by Ben
Henning using premake.

The necessity for this comes from the fact that SDL provides a hand crafted
selection of Visual Studio Solutions and XCode project files, which are
used both by SDL devs to build binary releases and by users wishing to
compile the library on their own. On top of this, SDL supports the
traditional *nix method of configure && make, and even a CMake based
solution. In the interest of reducing maintenance tasks related to this
wide variety of build systems (a typical single file addition to SDL’s code
base would imply editing perhaps a dozen or more files), we wanted to
develop a build system that could take a minimal number of configuration
files, and based on them build as many of the aforementioned solutions and
projects automatically. Thanks to Ben, we now have such a system, based on
a slightly tweaked premake 5 system. While we set out to replace just our
Visual Studio and XCode projects, we ended up with a few extra bonuses,
such as iOS projects generation, some preliminary Linux support, etc.

Ben’s code (also soon to be merged into mainline SDL) can be found here:

Ben’s blog, where he gives insight on the GSOC experience as well as
technical details on the project, is at:

Thanks goes out to all the students who applied for SDL’s GSoC projects,
Ben and Apoorv for participating in GSoC 2013 this year, Andreas and
Gabriel for mentoring, Sam and Ryan for the support, and Google for their
support of open source software in this way.

Now its time for the SDL community to take over. Happy testing and building!