Train yourself to instantly know the right-of-way rules!

I feel that one needs a lot of practice in order to get the theory right (at least I do). So I wrote this little game for myself.

There is a Windows executable here. It is built using Windows 10; please open a GitHub Issue if you find out if it works with older versions!

You are the car coming from the bottom of the screen.

Press the arrow key corresponding to the correct driving direction within 20 seconds! To yield (stop the car and let someone else pass), press the down arrow. Also works with WASD controls.

On pressing the key, the game pauses, and you get immediate feedback. To resume the game, press any key. The game quits after you make a mistake.

The final score is currently printed at the top of the screen (end of the text line).

Feel free to submit pull requests or suggestions!

You should read the rules in a driving manual first (and you may not blame me if you can't learn to drive after playing this). Also, you need a driving license to drive in most countries.

Here's what I implemented (stricter version of European rules):

1. If there are no other cars that would intersect your path, you must go through.
2. If you are the only one with a right-of-way/priority sign, you must go through first.
3. If the other cars have a yield sign and you don't, then you must also go through first.
4. If everyone has the same level of right-of-way, then you must yield to the vehicle coming from your right, if there is one.

• There are two kinds of "coming from your right":
  • before you enter the intersection, the car is on the road to your right
  • after you enter the intersection, you would turn left (and a car is coming from the road ahead or from the right). This way, if you were to go left, the other car coming from ahead (North) would hit your right.

5. If you are opposite of someone and both of you want to turn left, in this game you must yield. In practice though, you might be able to go through if both of you keep left of the intersection's center. But I didn't want to code this in the game, and I wouldn't do it in reality either.

The project requires Python 3, pip, and PyGame.

To install Pygame:

• On Windows: pip install pygame
• On Debian: python3 -m pip install pygame

To build the Windows exe from source, you need PyInstaller and a Windows machine. Then, run winbuild.bat.

Future possibilities:

• stop sign as a random possibility instead of yield sign
  • should stop even if there are no cars
• Image editing: remove car from signal images; stack signal lights over car image instead
• make player car color customizable
• simulate continuation after selecting direction
  • Figure out trigonometrics of turning
  • crashes, explosions and fire! (also sounds)