This is not a game SDK. It is a finished X11 demo: an analog or digital clock in front of a slowly tumbling GL cube. You own clock.c end to end — Display, GLX, XCB, redraw.
Fork it if you want another “one window, GL overlay, X events on the side” toy. There is no tick API to implement.
Linux / WSL only:
make
./xcb-clockNeeds X11, XCB, GL, GLU, GLX (pkg-config).
- Analog face or digital digits, toggled with the on-screen switch (click) or keys.
- The cube is GL behind the 2D overlay. Arrow keys add spin.
- Time comes from the machine clock each frame.
| Key | Action |
|---|---|
| Click the toggle | Analog ↔ digital |
| Arrows | Nudge cube rotation |
| Q / Esc / close | Quit |
If you change the demo, stay in clock.c. Window size, colors, and the cube live in the same file as the event loop.