view docs/man3/SDL_keysym.3 @ 2318:0c653886cce7

HandleEvent() returns done each time it is called. If done was set to 0 the program should quit, but because done is not checked until *all* events are handled a following event can reset done to 1 and prevent the program from terminating when told to. I fixed the while loop that handles events to check for the state of done after handling each event. That could leave some events unhandled when the program exits, but it ensures that the program will exit.
author Bob Pendleton <bob@pendleton.com>
date Wed, 20 Feb 2008 23:27:33 +0000
parents 546f7c1eb755
children 1238da4a7112
line wrap: on
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.TH "SDL_keysym" "3" "Tue 11 Sep 2001, 23:00" "SDL" "SDL API Reference" 
.SH "NAME"
SDL_keysym \- Keysym structure
.SH "STRUCTURE DEFINITION"
.PP
.nf
\f(CWtypedef struct{
  Uint8 scancode;
  SDLKey sym;
  SDLMod mod;
  Uint16 unicode;
} SDL_keysym;\fR
.fi
.PP
.SH "STRUCTURE DATA"
.TP 20
\fBscancode\fR
Hardware specific scancode
.TP 20
\fBsym\fR
SDL virtual keysym
.TP 20
\fBmod\fR
Current key modifiers
.TP 20
\fBunicode\fR
Translated character
.SH "DESCRIPTION"
.PP
The \fBSDL_keysym\fR structure is used by reporting key presses and releases since it is a part of the \fI\fBSDL_KeyboardEvent\fR\fR\&.
.PP
The \fBscancode\fR field should generally be left alone, it is the hardware dependent scancode returned by the keyboard\&. The \fBsym\fR field is extremely useful\&. It is the SDL-defined value of the key (see \fISDL Key Syms\fR\&. This field is very useful when you are checking for certain key presses, like so: 
.PP
.nf
\f(CW\&.
\&.
while(SDL_PollEvent(&event)){
  switch(event\&.type){
    case SDL_KEYDOWN:
      if(event\&.key\&.keysym\&.sym==SDLK_LEFT)
        move_left();
      break;
    \&.
    \&.
    \&.
  }
}
\&.
\&.\fR
.fi
.PP
 \fBmod\fR stores the current state of the keyboard modifiers as explained in \fI\fBSDL_GetModState\fP\fR\&. The \fBunicode\fR is only used when UNICODE translation is enabled with \fI\fBSDL_EnableUNICODE\fP\fR\&. If \fBunicode\fR 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: 
.PP
.nf
\f(CWchar ch;
if ( (keysym\&.unicode & 0xFF80) == 0 ) {
  ch = keysym\&.unicode & 0x7F;
}
else {
  printf("An International Character\&.
");
}\fR
.fi
.PP
 UNICODE translation does have a slight overhead so don\&'t enable it unless its needed\&.
.SH "SEE ALSO"
.PP
\fI\fBSDLKey\fR\fR
...\" created by instant / docbook-to-man, Tue 11 Sep 2001, 23:00