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SDL_keysym

NAME

SDL_keysym- Keysym structure

STRUCTURE DEFINITION

typedef struct{

  Uint8 scancode;

  SDLKey sym;

  SDLMod mod;

  Uint16 unicode;

} SDL_keysym;

STRUCTURE DATA

scancode

Hardware specific scancode

sym

SDL virtual keysym

mod

Current key modifiers

unicode

Translated character

DESCRIPTION

The SDL_keysym structure is used by reporting key presses and releases since it is a part of the SDL_KeyboardEvent.

The scancode field should generally be left alone, it is the hardware dependent scancode returned by the keyboard. The sym field is extremely useful. It is the SDL-defined value of the key (see SDL Key Syms. This field is very useful when you are checking for certain key presses, like so:

.

.

while(SDL_PollEvent(&event)){

  switch(event.type){

    case SDL_KEYDOWN:

      if(event.key.keysym.sym==SDLK_LEFT)

        move_left();

      break;

    .

    .

    .

  }

}

.

.

 mod stores the current state of the keyboard modifiers as explained in SDL_GetModState. The unicode is only used when UNICODE translation is enabled with SDL_EnableUNICODE. If unicode is non-zero then this a the UNICODE character corresponding to the keypress. If the high 9 bits of the character are 0, then this maps to the equivalent ASCII character: 

char ch;

if ( (keysym.unicode & 0xFF80) == 0 ) {

  ch = keysym.unicode & 0x7F;

}

else {

  printf("An International Character.

");

}

 UNICODE translation does have a slight overhead so don't enable it unless its needed.

SEE ALSO

SDLKey