x11_gl_alsa_freetype_challenge

Making a game for Linux with the system-provided APIs, in two days.

The challenge

Make a game for Linux with no "external" run-time dependencies such as SDL2, within a normal week-end.

At least C11 with the -Wall option or similar (and compilation should not generate warnings);

Portability should be considered, but is not mandatory;

Write everything, including the Makefile, by hand;

When looking for docs/references, try each of these in order :

1. man pages;
2. The sources for official examples (e.g xev, aplay);
3. Official docs on the Web;
4. The source of external libraries (e.g SDL2, SFML);
5. Other online resources such as StackOverflow and forums.

Avoid copy-and-pasting.

More or less follow Rust's style with regards to case for type vs. variable names, etc.

Day 1

The game's codename is "dsky", short for "dracosky", a far earlier attempt at a game jam with SDL2.

The game successfully:

• Creates and configures an X11 window and cursor;
• Receives and handles events;
• Creates a modern (3.0+) compatibility-profile debug OpenGL context, and enables late-swap-tearing, or Vsync if it fails;
• Loads a 1024x1024 texture from raw RGBA data exported with GIMP;
• Compiles a basic GLSL 1.30 program and uses it to display the background image;
• Loads a 16-bit PCM WAV file exported with Audacity;
• Plays the WAV file with ALSA's user-space API, using a blocking write on a separate thread.

What's left to fix for day 2:

• The audio content is not mine, neither is the background image;
• The screen's size, the window's size, the texture's size, some settings of the WAV and the GLX presence and version are just assumed and hard-coded;
• Proper platform-specific code isolation is not achieved;

Extra features I'd like to add:

• Full-screen support;
• Camera shaking effect;
• Some text rendering;

The game avoids matrices like the plague because I'm too lazy to implement them, but obviously I'd care if it was something I would ship.

Day 2

For reasons, Day 2 was actually split into small periods of time the few following days. These were mostly improvements over Day 1, and I've lost track of these. I'll let the commits speak for themselves I guess ???

Dependencies

You should be fine running the executable (if I distribute one) out-of-the-box on amd64, however for compiling you'll need (provided I haven't left out anything):

• Ubuntu: `sudo apt install -y libx11-dev libasound2-dev libfreetype6-dev libgl1-mesa-dev