view include/SDL_keyboard.h @ 765:4c2ba6161939

Editors Note: The original patch was modified to use SDL_Delay() instead of nanosleep because nanosleep may not be portable to all systems using SDL with the ALSA backend. This may be a moot point with the switch to blocking writes anyway... Date: Sat, 27 Dec 2003 21:47:36 +0100 From: Michel Daenzer To: Debian Bug Tracking System Subject: [SDL] Bug#225252: [PATCH] ALSA fixes Package: libsdl1.2debian-all Version: 1.2.6-2 Severity: normal Tags: patch For SDL 1.2.6, the ALSA backend was changed to call snd_pcm_open() with SND_PCM_NONBLOCK. That's a good idea per se, however, it causes high CPU usage, interrupted sound and stuttering in some games here. Taking a nanosleep whenever snd_pcm_writei() returns -EAGAIN fixes this, but I think it's more efficient to use blocking mode for the actual sound playback. Feedback from the SDL and ALSA lists appreciated. The patch also fixes the default ALSA device to be used.
author Sam Lantinga <slouken@libsdl.org>
date Sun, 04 Jan 2004 15:40:50 +0000
parents 9154ec9ca3d2
children b8d311d90021
line wrap: on
line source

/*
    SDL - Simple DirectMedia Layer
    Copyright (C) 1997, 1998, 1999, 2000, 2001, 2002  Sam Lantinga

    This library is free software; you can redistribute it and/or
    modify it under the terms of the GNU Library General Public
    License as published by the Free Software Foundation; either
    version 2 of the License, or (at your option) any later version.

    This library is distributed in the hope that it will be useful,
    but WITHOUT ANY WARRANTY; without even the implied warranty of
    MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
    Library General Public License for more details.

    You should have received a copy of the GNU Library General Public
    License along with this library; if not, write to the Free
    Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA  02111-1307  USA

    Sam Lantinga
    slouken@libsdl.org
*/

#ifdef SAVE_RCSID
static char rcsid =
 "@(#) $Id$";
#endif

/* Include file for SDL keyboard event handling */

#ifndef _SDL_keyboard_h
#define _SDL_keyboard_h

#include "SDL_types.h"
#include "SDL_keysym.h"

#include "begin_code.h"
/* Set up for C function definitions, even when using C++ */
#ifdef __cplusplus
extern "C" {
#endif

/* Keysym structure
   - The scancode is hardware dependent, and should not be used by general
     applications.  If no hardware scancode is available, it will be 0.

   - The 'unicode' translated character is only available when character
     translation is enabled by the SDL_EnableUNICODE() API.  If non-zero,
     this is a 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 {
		An international character..
	}
 */
typedef struct {
	Uint8 scancode;			/* hardware specific scancode */
	SDLKey sym;			/* SDL virtual keysym */
	SDLMod mod;			/* current key modifiers */
	Uint16 unicode;			/* translated character */
} SDL_keysym;

/* This is the mask which refers to all hotkey bindings */
#define SDL_ALL_HOTKEYS		0xFFFFFFFF

/* Function prototypes */
/*
 * Enable/Disable UNICODE translation of keyboard input.
 * This translation has some overhead, so translation defaults off.
 * If 'enable' is 1, translation is enabled.
 * If 'enable' is 0, translation is disabled.
 * If 'enable' is -1, the translation state is not changed.
 * It returns the previous state of keyboard translation.
 */
extern DECLSPEC int SDLCALL SDL_EnableUNICODE(int enable);

/*
 * Enable/Disable keyboard repeat.  Keyboard repeat defaults to off.
 * 'delay' is the initial delay in ms between the time when a key is
 * pressed, and keyboard repeat begins.
 * 'interval' is the time in ms between keyboard repeat events.
 */
#define SDL_DEFAULT_REPEAT_DELAY	500
#define SDL_DEFAULT_REPEAT_INTERVAL	30
/*
 * If 'delay' is set to 0, keyboard repeat is disabled.
 */
extern DECLSPEC int SDLCALL SDL_EnableKeyRepeat(int delay, int interval);

/*
 * Get a snapshot of the current state of the keyboard.
 * Returns an array of keystates, indexed by the SDLK_* syms.
 * Used:
 * 	Uint8 *keystate = SDL_GetKeyState(NULL);
 *	if ( keystate[SDLK_RETURN] ) ... <RETURN> is pressed.
 */
extern DECLSPEC Uint8 * SDLCALL SDL_GetKeyState(int *numkeys);

/*
 * Get the current key modifier state
 */
extern DECLSPEC SDLMod SDLCALL SDL_GetModState(void);

/*
 * Set the current key modifier state
 * This does not change the keyboard state, only the key modifier flags.
 */
extern DECLSPEC void SDLCALL SDL_SetModState(SDLMod modstate);

/*
 * Get the name of an SDL virtual keysym
 */
extern DECLSPEC char * SDLCALL SDL_GetKeyName(SDLKey key);


/* Ends C function definitions when using C++ */
#ifdef __cplusplus
}
#endif
#include "close_code.h"

#endif /* _SDL_keyboard_h */