Mercurial > sdl-ios-xcode
view include/SDL_events.h @ 942:41a59de7f2ed
Here are patches for SDL12 and SDL_mixer for 4 or 6 channel
surround sound on Linux using the Alsa driver. To use them, naturally
you need a sound card that will do 4 or 6 channels and probably also a
recent version of the Alsa drivers and library. Since the only SDL
output driver that knows about surround sound is the Alsa driver,
you���ll want to choose it, using:
export SDL_AUDIODRIVER=alsa
There are no syntactic changes to the programming API. No new
library calls, no differences in arguments.
There are two semantic changes:
(1) For library calls with number of channels as an argument, formerly
you could use only 1 or 2 for the number of channels. Now you
can also use 4 or 6.
(2) The two "left" and "right" arguments to Mix_SetPanning, for the
case of 4 or 6 channels, no longer simply control the volumes of
the left and right channels. Now the "left" argument is converted
to an angle and Mix_SetPosition is called, and the "right" argu-
ment is ignored.
With two exceptions, so far as I know, the modified SDL12 and
SDL_mixer work the same way as the original versions, when opened for
1 or 2 channel output. The two exceptions are bugs which I fixed.
Well, the first, anyway, is a bug for sure. When rate conversions up
or down by a factor of two are applied (in src/audio/SDL_audiocvt.c),
streams with different numbers of channels (that is, mono and stereo)
are treated the same way: either each sample is copied or every other
sample is omitted. This is ok for mono, but for stereo, it is frames
that should be copied or omitted, where by "frame" I mean a portion of
the stream containing one sample for each channel. (In the SDL source,
confusingly, sometimes frames are called "samples".) So for these
rate conversions, stereo streams have to be treated differently, and
they are, in my modified version.
The other problem that might be characterized as a bug arises
when SDL_mixer is passed a multichannel chunk which does not have an
integral number of frames. Due to the way the effect_position code
loops over frames, when the chunk ends with a partial frame, memory
outside the chunk buffer will be accessed. In the case of stereo,
it���s possible that because malloc may give more memory than requested,
this potential problem never actually causes a segment fault. I don���t
know. For 6 channel chunks, I do know, and it does cause segment
faults.
If SDL_mixer is passed defective chunks and this causes a segment
fault, arguably, that���s not a bug in SDL_mixer. Still, whether or not
it counts as a bug, it���s easy to protect against, so why not? I added
code in mixer.c to discard any partial frame at the end of a chunk.
Then what about when SDL or SDL_mixer is opened for 4 or 6 chan-
nel output? What happens with the parts of the current library
designed for stereo? I don���t know whether I���ve covered all the bases,
but I���ve tried:
(1) For playing 2 channel waves, or other cases where SDL knows it has
to match up a 2 channel source with a 4 or 6 channel output, I���ve
added code in SDL_audiocvt.c to make the necessary conversions.
(2) For playing midis using timidity, I���ve converted timidity to do 4
or 6 channel output, upon request.
(3) For playing mods using mikmod, I put ad hoc code in music.c to
convert the stereo output that mikmod produces to 4 or 6 chan-
nels. Obviously it would be better to change the mikmod code to
mix down into 4 or 6 channels, but I have a hard time following
the code in mikmod, so I didn���t do that.
(4) For playing mp3s, I put ad hoc code in smpeg to copy channels in
the case when 4 or 6 channel output is needed.
(5) There seems to be no problem with .ogg files - stereo .oggs can be
up converted as .wavs are.
(6) The effect_position code in SDL_mixer is now generalized to in-
clude the cases of 4 and 6 channel streams.
I���ve done a very limited amount of compatibility testing for some
of the games using SDL I happen to have. For details, see the file
TESTS.
I���ve put into a separate archive, Surround-SDL-testfiles.tgz, a
couple of 6 channel wave files for testing and a 6 channel ogg file.
If you have the right hardware and version of Alsa, you should be able
to play the wave files with the Alsa utility aplay (and hear all
channels, except maybe lfe, for chan-id.wav, since it���s rather faint).
Don���t expect aplay to give good sound, though. There���s something
wrong with the current version of aplay.
The canyon.ogg file is to test loading of 6 channel oggs. After
patching and compiling, you can play it with playmus. (My version of
ogg123 will not play it, and I had to patch mplayer to get it to play
6 channel oggs.)
Greg Lee <greg@ling.lll.hawaii.edu>
Thus, July 1, 2004
author | Sam Lantinga <slouken@libsdl.org> |
---|---|
date | Sat, 21 Aug 2004 12:27:02 +0000 |
parents | 02759105b989 |
children | b2283b0ded26 |
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/* SDL - Simple DirectMedia Layer Copyright (C) 1997-2004 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 event handling */ #ifndef _SDL_events_h #define _SDL_events_h #include "SDL_types.h" #include "SDL_active.h" #include "SDL_keyboard.h" #include "SDL_mouse.h" #include "SDL_joystick.h" #include "SDL_quit.h" #include "begin_code.h" /* Set up for C function definitions, even when using C++ */ #ifdef __cplusplus extern "C" { #endif /* Event enumerations */ enum { SDL_NOEVENT = 0, /* Unused (do not remove) */ SDL_ACTIVEEVENT, /* Application loses/gains visibility */ SDL_KEYDOWN, /* Keys pressed */ SDL_KEYUP, /* Keys released */ SDL_MOUSEMOTION, /* Mouse moved */ SDL_MOUSEBUTTONDOWN, /* Mouse button pressed */ SDL_MOUSEBUTTONUP, /* Mouse button released */ SDL_JOYAXISMOTION, /* Joystick axis motion */ SDL_JOYBALLMOTION, /* Joystick trackball motion */ SDL_JOYHATMOTION, /* Joystick hat position change */ SDL_JOYBUTTONDOWN, /* Joystick button pressed */ SDL_JOYBUTTONUP, /* Joystick button released */ SDL_QUIT, /* User-requested quit */ SDL_SYSWMEVENT, /* System specific event */ SDL_EVENT_RESERVEDA, /* Reserved for future use.. */ SDL_EVENT_RESERVEDB, /* Reserved for future use.. */ SDL_VIDEORESIZE, /* User resized video mode */ SDL_VIDEOEXPOSE, /* Screen needs to be redrawn */ SDL_EVENT_RESERVED2, /* Reserved for future use.. */ SDL_EVENT_RESERVED3, /* Reserved for future use.. */ SDL_EVENT_RESERVED4, /* Reserved for future use.. */ SDL_EVENT_RESERVED5, /* Reserved for future use.. */ SDL_EVENT_RESERVED6, /* Reserved for future use.. */ SDL_EVENT_RESERVED7, /* Reserved for future use.. */ /* Events SDL_USEREVENT through SDL_MAXEVENTS-1 are for your use */ SDL_USEREVENT = 24, /* This last event is only for bounding internal arrays It is the number of bits in the event mask datatype -- Uint32 */ SDL_NUMEVENTS = 32 }; /* Predefined event masks */ #define SDL_EVENTMASK(X) (1<<(X)) enum { SDL_ACTIVEEVENTMASK = SDL_EVENTMASK(SDL_ACTIVEEVENT), SDL_KEYDOWNMASK = SDL_EVENTMASK(SDL_KEYDOWN), SDL_KEYUPMASK = SDL_EVENTMASK(SDL_KEYUP), SDL_MOUSEMOTIONMASK = SDL_EVENTMASK(SDL_MOUSEMOTION), SDL_MOUSEBUTTONDOWNMASK = SDL_EVENTMASK(SDL_MOUSEBUTTONDOWN), SDL_MOUSEBUTTONUPMASK = SDL_EVENTMASK(SDL_MOUSEBUTTONUP), SDL_MOUSEEVENTMASK = SDL_EVENTMASK(SDL_MOUSEMOTION)| SDL_EVENTMASK(SDL_MOUSEBUTTONDOWN)| SDL_EVENTMASK(SDL_MOUSEBUTTONUP), SDL_JOYAXISMOTIONMASK = SDL_EVENTMASK(SDL_JOYAXISMOTION), SDL_JOYBALLMOTIONMASK = SDL_EVENTMASK(SDL_JOYBALLMOTION), SDL_JOYHATMOTIONMASK = SDL_EVENTMASK(SDL_JOYHATMOTION), SDL_JOYBUTTONDOWNMASK = SDL_EVENTMASK(SDL_JOYBUTTONDOWN), SDL_JOYBUTTONUPMASK = SDL_EVENTMASK(SDL_JOYBUTTONUP), SDL_JOYEVENTMASK = SDL_EVENTMASK(SDL_JOYAXISMOTION)| SDL_EVENTMASK(SDL_JOYBALLMOTION)| SDL_EVENTMASK(SDL_JOYHATMOTION)| SDL_EVENTMASK(SDL_JOYBUTTONDOWN)| SDL_EVENTMASK(SDL_JOYBUTTONUP), SDL_VIDEORESIZEMASK = SDL_EVENTMASK(SDL_VIDEORESIZE), SDL_VIDEOEXPOSEMASK = SDL_EVENTMASK(SDL_VIDEOEXPOSE), SDL_QUITMASK = SDL_EVENTMASK(SDL_QUIT), SDL_SYSWMEVENTMASK = SDL_EVENTMASK(SDL_SYSWMEVENT) }; #define SDL_ALLEVENTS 0xFFFFFFFF /* Application visibility event structure */ typedef struct SDL_ActiveEvent { Uint8 type; /* SDL_ACTIVEEVENT */ Uint8 gain; /* Whether given states were gained or lost (1/0) */ Uint8 state; /* A mask of the focus states */ } SDL_ActiveEvent; /* Keyboard event structure */ typedef struct SDL_KeyboardEvent { Uint8 type; /* SDL_KEYDOWN or SDL_KEYUP */ Uint8 which; /* The keyboard device index */ Uint8 state; /* SDL_PRESSED or SDL_RELEASED */ SDL_keysym keysym; } SDL_KeyboardEvent; /* Mouse motion event structure */ typedef struct SDL_MouseMotionEvent { Uint8 type; /* SDL_MOUSEMOTION */ Uint8 which; /* The mouse device index */ Uint8 state; /* The current button state */ Uint16 x, y; /* The X/Y coordinates of the mouse */ Sint16 xrel; /* The relative motion in the X direction */ Sint16 yrel; /* The relative motion in the Y direction */ } SDL_MouseMotionEvent; /* Mouse button event structure */ typedef struct SDL_MouseButtonEvent { Uint8 type; /* SDL_MOUSEBUTTONDOWN or SDL_MOUSEBUTTONUP */ Uint8 which; /* The mouse device index */ Uint8 button; /* The mouse button index */ Uint8 state; /* SDL_PRESSED or SDL_RELEASED */ Uint16 x, y; /* The X/Y coordinates of the mouse at press time */ } SDL_MouseButtonEvent; /* Joystick axis motion event structure */ typedef struct SDL_JoyAxisEvent { Uint8 type; /* SDL_JOYAXISMOTION */ Uint8 which; /* The joystick device index */ Uint8 axis; /* The joystick axis index */ Sint16 value; /* The axis value (range: -32768 to 32767) */ } SDL_JoyAxisEvent; /* Joystick trackball motion event structure */ typedef struct SDL_JoyBallEvent { Uint8 type; /* SDL_JOYBALLMOTION */ Uint8 which; /* The joystick device index */ Uint8 ball; /* The joystick trackball index */ Sint16 xrel; /* The relative motion in the X direction */ Sint16 yrel; /* The relative motion in the Y direction */ } SDL_JoyBallEvent; /* Joystick hat position change event structure */ typedef struct SDL_JoyHatEvent { Uint8 type; /* SDL_JOYHATMOTION */ Uint8 which; /* The joystick device index */ Uint8 hat; /* The joystick hat index */ Uint8 value; /* The hat position value: SDL_HAT_LEFTUP SDL_HAT_UP SDL_HAT_RIGHTUP SDL_HAT_LEFT SDL_HAT_CENTERED SDL_HAT_RIGHT SDL_HAT_LEFTDOWN SDL_HAT_DOWN SDL_HAT_RIGHTDOWN Note that zero means the POV is centered. */ } SDL_JoyHatEvent; /* Joystick button event structure */ typedef struct SDL_JoyButtonEvent { Uint8 type; /* SDL_JOYBUTTONDOWN or SDL_JOYBUTTONUP */ Uint8 which; /* The joystick device index */ Uint8 button; /* The joystick button index */ Uint8 state; /* SDL_PRESSED or SDL_RELEASED */ } SDL_JoyButtonEvent; /* The "window resized" event When you get this event, you are responsible for setting a new video mode with the new width and height. */ typedef struct SDL_ResizeEvent { Uint8 type; /* SDL_VIDEORESIZE */ int w; /* New width */ int h; /* New height */ } SDL_ResizeEvent; /* The "screen redraw" event */ typedef struct SDL_ExposeEvent { Uint8 type; /* SDL_VIDEOEXPOSE */ } SDL_ExposeEvent; /* The "quit requested" event */ typedef struct SDL_QuitEvent { Uint8 type; /* SDL_QUIT */ } SDL_QuitEvent; /* A user-defined event type */ typedef struct SDL_UserEvent { Uint8 type; /* SDL_USEREVENT through SDL_NUMEVENTS-1 */ int code; /* User defined event code */ void *data1; /* User defined data pointer */ void *data2; /* User defined data pointer */ } SDL_UserEvent; /* If you want to use this event, you should include SDL_syswm.h */ struct SDL_SysWMmsg; typedef struct SDL_SysWMmsg SDL_SysWMmsg; typedef struct SDL_SysWMEvent { Uint8 type; SDL_SysWMmsg *msg; } SDL_SysWMEvent; /* General event structure */ typedef union { Uint8 type; SDL_ActiveEvent active; SDL_KeyboardEvent key; SDL_MouseMotionEvent motion; SDL_MouseButtonEvent button; SDL_JoyAxisEvent jaxis; SDL_JoyBallEvent jball; SDL_JoyHatEvent jhat; SDL_JoyButtonEvent jbutton; SDL_ResizeEvent resize; SDL_ExposeEvent expose; SDL_QuitEvent quit; SDL_UserEvent user; SDL_SysWMEvent syswm; } SDL_Event; /* Function prototypes */ /* Pumps the event loop, gathering events from the input devices. This function updates the event queue and internal input device state. This should only be run in the thread that sets the video mode. */ extern DECLSPEC void SDLCALL SDL_PumpEvents(void); /* Checks the event queue for messages and optionally returns them. If 'action' is SDL_ADDEVENT, up to 'numevents' events will be added to the back of the event queue. If 'action' is SDL_PEEKEVENT, up to 'numevents' events at the front of the event queue, matching 'mask', will be returned and will not be removed from the queue. If 'action' is SDL_GETEVENT, up to 'numevents' events at the front of the event queue, matching 'mask', will be returned and will be removed from the queue. This function returns the number of events actually stored, or -1 if there was an error. This function is thread-safe. */ typedef enum { SDL_ADDEVENT, SDL_PEEKEVENT, SDL_GETEVENT } SDL_eventaction; /* */ extern DECLSPEC int SDLCALL SDL_PeepEvents(SDL_Event *events, int numevents, SDL_eventaction action, Uint32 mask); /* Polls for currently pending events, and returns 1 if there are any pending events, or 0 if there are none available. If 'event' is not NULL, the next event is removed from the queue and stored in that area. */ extern DECLSPEC int SDLCALL SDL_PollEvent(SDL_Event *event); /* Waits indefinitely for the next available event, returning 1, or 0 if there was an error while waiting for events. If 'event' is not NULL, the next event is removed from the queue and stored in that area. */ extern DECLSPEC int SDLCALL SDL_WaitEvent(SDL_Event *event); /* Add an event to the event queue. This function returns 0 on success, or -1 if the event queue was full or there was some other error. */ extern DECLSPEC int SDLCALL SDL_PushEvent(SDL_Event *event); /* This function sets up a filter to process all events before they change internal state and are posted to the internal event queue. The filter is protypted as: */ typedef int (SDLCALL *SDL_EventFilter)(const SDL_Event *event); /* If the filter returns 1, then the event will be added to the internal queue. If it returns 0, then the event will be dropped from the queue, but the internal state will still be updated. This allows selective filtering of dynamically arriving events. WARNING: Be very careful of what you do in the event filter function, as it may run in a different thread! There is one caveat when dealing with the SDL_QUITEVENT event type. The event filter is only called when the window manager desires to close the application window. If the event filter returns 1, then the window will be closed, otherwise the window will remain open if possible. If the quit event is generated by an interrupt signal, it will bypass the internal queue and be delivered to the application at the next event poll. */ extern DECLSPEC void SDLCALL SDL_SetEventFilter(SDL_EventFilter filter); /* Return the current event filter - can be used to "chain" filters. If there is no event filter set, this function returns NULL. */ extern DECLSPEC SDL_EventFilter SDLCALL SDL_GetEventFilter(void); /* This function allows you to set the state of processing certain events. If 'state' is set to SDL_IGNORE, that event will be automatically dropped from the event queue and will not event be filtered. If 'state' is set to SDL_ENABLE, that event will be processed normally. If 'state' is set to SDL_QUERY, SDL_EventState() will return the current processing state of the specified event. */ #define SDL_QUERY -1 #define SDL_IGNORE 0 #define SDL_DISABLE 0 #define SDL_ENABLE 1 extern DECLSPEC Uint8 SDLCALL SDL_EventState(Uint8 type, int state); /* Ends C function definitions when using C++ */ #ifdef __cplusplus } #endif #include "close_code.h" #endif /* _SDL_events_h */