Why there is no SDLK_COLON equivalent scancode in SDL2?

Question

I'm trying to check if the colon key is pressed, I'm using a English keyboard which means colon is shift + ;, my though was to read the keyboard state and then check the status of the scancode:

  SDL_PumpEvents();
  const uint8 *keyState = SDL_GetKeyboardState(NULL);

  printf("keystate %d\n", keyState[scancode]);

but then I realized there is a scancode for the keypad colon SDL_SCANCODE_KP_COLON equivalent toSDLK_KP_COLON, but there is no scancode for SDLK_COLON (In case you are wondering: I tried with the keypad version and is not working).

So, I wonder why there is no equivalent scancode for SDLK_COLON and what's the best way to do this instead?

Answer 1

There is no colon scancode because there is no key on an ANSI (US) layout keyboard that produces a colon without modifiers. SDLK_COLON exists because there are layouts where a key produces a colon without modifier, like the French layout where the key corresponding to SDL_SCANCODE_PERIOD (dot . or greater-than sign >) makes a colon : or a slash / (with shift). So if you press that key on a French keyboard, you receive an event with SDL_SCANCODE_PERIOD and SDLK_COLON.

What I assume you want is to know if the user typed a colon, which has nothing to do with scancodes or even keycodes when dealing with different keyboard layouts. For that, you need a SDL_TextInputEvent. Check out the wiki's tutorial about it.

Or you could use SDL_SCANCODE_SEMICOLON, check what that key corresponds to for the user, and display that so the user knows what key to press (it would be the ù key for a French keyboard).