Mercurial > sdl-ios-xcode
view src/main/macos/SDL_main.c @ 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 | b8d311d90021 |
children | 609c060fd2a2 |
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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 /* This file takes care of command line argument parsing, and stdio redirection in the MacOS environment. */ #include <stdio.h> #include <stdlib.h> #include <string.h> #include <ctype.h> #if TARGET_API_MAC_CARBON #include <Carbon.h> #else #include <Dialogs.h> #include <Fonts.h> #include <Events.h> #include <Resources.h> #include <Folders.h> #endif /* Include the SDL main definition header */ #include "SDL.h" #include "SDL_main.h" #ifdef main #undef main #endif /* The standard output files */ #define STDOUT_FILE "stdout.txt" #define STDERR_FILE "stderr.txt" #if !defined(__MWERKS__) && !TARGET_API_MAC_CARBON /* In MPW, the qd global has been removed from the libraries */ QDGlobals qd; #endif /* Structure for keeping prefs in 1 variable */ typedef struct { Str255 command_line; Str255 video_driver_name; Boolean output_to_file; } PrefsRecord; /* See if the command key is held down at startup */ static Boolean CommandKeyIsDown(void) { KeyMap theKeyMap; GetKeys(theKeyMap); if (((unsigned char *) theKeyMap)[6] & 0x80) { return(true); } return(false); } /* Parse a command line buffer into arguments */ static int ParseCommandLine(char *cmdline, char **argv) { char *bufp; int argc; argc = 0; for ( bufp = cmdline; *bufp; ) { /* Skip leading whitespace */ while ( isspace(*bufp) ) { ++bufp; } /* Skip over argument */ if ( *bufp == '"' ) { ++bufp; if ( *bufp ) { if ( argv ) { argv[argc] = bufp; } ++argc; } /* Skip over word */ while ( *bufp && (*bufp != '"') ) { ++bufp; } } else { if ( *bufp ) { if ( argv ) { argv[argc] = bufp; } ++argc; } /* Skip over word */ while ( *bufp && ! isspace(*bufp) ) { ++bufp; } } if ( *bufp ) { if ( argv ) { *bufp = '\0'; } ++bufp; } } if ( argv ) { argv[argc] = NULL; } return(argc); } /* Remove the output files if there was no output written */ static void cleanup_output(void) { FILE *file; int empty; /* Flush the output in case anything is queued */ fclose(stdout); fclose(stderr); /* See if the files have any output in them */ file = fopen(STDOUT_FILE, "rb"); if ( file ) { empty = (fgetc(file) == EOF) ? 1 : 0; fclose(file); if ( empty ) { remove(STDOUT_FILE); } } file = fopen(STDERR_FILE, "rb"); if ( file ) { empty = (fgetc(file) == EOF) ? 1 : 0; fclose(file); if ( empty ) { remove(STDERR_FILE); } } } static int getCurrentAppName (StrFileName name) { ProcessSerialNumber process; ProcessInfoRec process_info; FSSpec process_fsp; process.highLongOfPSN = 0; process.lowLongOfPSN = kCurrentProcess; process_info.processInfoLength = sizeof (process_info); process_info.processName = NULL; process_info.processAppSpec = &process_fsp; if ( noErr != GetProcessInformation (&process, &process_info) ) return 0; memcpy (name, process_fsp.name, process_fsp.name[0] + 1); return 1; } static int getPrefsFile (FSSpec *prefs_fsp, int create) { /* The prefs file name is the application name, possibly truncated, */ /* plus " Preferences */ #define SUFFIX " Preferences" #define MAX_NAME 19 /* 31 - strlen (SUFFIX) */ short volume_ref_number; long directory_id; StrFileName prefs_name; StrFileName app_name; /* Get Preferences folder - works with Multiple Users */ if ( noErr != FindFolder ( kOnSystemDisk, kPreferencesFolderType, kDontCreateFolder, &volume_ref_number, &directory_id) ) exit (-1); if ( ! getCurrentAppName (app_name) ) exit (-1); /* Truncate if name is too long */ if (app_name[0] > MAX_NAME ) app_name[0] = MAX_NAME; memcpy (prefs_name + 1, app_name + 1, app_name[0]); memcpy (prefs_name + app_name[0] + 1, SUFFIX, strlen (SUFFIX)); prefs_name[0] = app_name[0] + strlen (SUFFIX); /* Make the file spec for prefs file */ if ( noErr != FSMakeFSSpec (volume_ref_number, directory_id, prefs_name, prefs_fsp) ) if ( !create ) return 0; else { /* Create the prefs file */ memcpy (prefs_fsp->name, prefs_name, prefs_name[0] + 1); prefs_fsp->parID = directory_id; prefs_fsp->vRefNum = volume_ref_number; FSpCreateResFile (prefs_fsp, '????', 'pref', 0); if ( noErr != ResError () ) return 0; } return 1; } static int readPrefsResource (PrefsRecord *prefs) { Handle prefs_handle; prefs_handle = Get1Resource( 'CLne', 128 ); if (prefs_handle != NULL) { int offset = 0; int j = 0; HLock(prefs_handle); /* Get command line string */ memcpy (prefs->command_line, *prefs_handle, (*prefs_handle)[0]+1); /* Get video driver name */ offset += (*prefs_handle)[0] + 1; memcpy (prefs->video_driver_name, *prefs_handle + offset, (*prefs_handle)[offset] + 1); /* Get save-to-file option (1 or 0) */ offset += (*prefs_handle)[offset] + 1; prefs->output_to_file = (*prefs_handle)[offset]; ReleaseResource( prefs_handle ); return ResError() == noErr; } return 0; } static int writePrefsResource (PrefsRecord *prefs, short resource_file) { Handle prefs_handle; UseResFile (resource_file); prefs_handle = Get1Resource ( 'CLne', 128 ); if (prefs_handle != NULL) RemoveResource (prefs_handle); prefs_handle = NewHandle ( prefs->command_line[0] + prefs->video_driver_name[0] + 4 ); if (prefs_handle != NULL) { int offset; HLock (prefs_handle); /* Command line text */ offset = 0; memcpy (*prefs_handle, prefs->command_line, prefs->command_line[0] + 1); /* Video driver name */ offset += prefs->command_line[0] + 1; memcpy (*prefs_handle + offset, prefs->video_driver_name, prefs->video_driver_name[0] + 1); /* Output-to-file option */ offset += prefs->video_driver_name[0] + 1; *( *((char**)prefs_handle) + offset) = (char)prefs->output_to_file; *( *((char**)prefs_handle) + offset + 1) = 0; AddResource (prefs_handle, 'CLne', 128, "\pCommand Line"); WriteResource (prefs_handle); UpdateResFile (resource_file); DisposeHandle (prefs_handle); return ResError() == noErr; } return 0; } static int readPreferences (PrefsRecord *prefs) { int no_error = 1; FSSpec prefs_fsp; /* Check for prefs file first */ if ( getPrefsFile (&prefs_fsp, 0) ) { short prefs_resource; prefs_resource = FSpOpenResFile (&prefs_fsp, fsRdPerm); if ( prefs_resource == -1 ) /* this shouldn't happen, but... */ return 0; UseResFile (prefs_resource); no_error = readPrefsResource (prefs); CloseResFile (prefs_resource); } /* Fall back to application's resource fork (reading only, so this is safe) */ else { no_error = readPrefsResource (prefs); } return no_error; } static int writePreferences (PrefsRecord *prefs) { int no_error = 1; FSSpec prefs_fsp; /* Get prefs file, create if it doesn't exist */ if ( getPrefsFile (&prefs_fsp, 1) ) { short prefs_resource; prefs_resource = FSpOpenResFile (&prefs_fsp, fsRdWrPerm); if (prefs_resource == -1) return 0; no_error = writePrefsResource (prefs, prefs_resource); CloseResFile (prefs_resource); } return no_error; } /* This is where execution begins */ int main(int argc, char *argv[]) { #pragma unused(argc, argv) #define DEFAULT_ARGS "\p" /* pascal string for default args */ #define DEFAULT_VIDEO_DRIVER "\ptoolbox" /* pascal string for default video driver name */ #define DEFAULT_OUTPUT_TO_FILE 1 /* 1 == output to file, 0 == no output */ #define VIDEO_ID_DRAWSPROCKET 1 /* these correspond to popup menu choices */ #define VIDEO_ID_TOOLBOX 2 PrefsRecord prefs = { DEFAULT_ARGS, DEFAULT_VIDEO_DRIVER, DEFAULT_OUTPUT_TO_FILE }; int nargs; char **args; char *commandLine; StrFileName appNameText; int videodriver = VIDEO_ID_TOOLBOX; int settingsChanged = 0; long i; /* Kyle's SDL command-line dialog code ... */ #if !TARGET_API_MAC_CARBON InitGraf (&qd.thePort); InitFonts (); InitWindows (); InitMenus (); InitDialogs (nil); #endif InitCursor (); FlushEvents(everyEvent,0); #if !TARGET_API_MAC_CARBON MaxApplZone (); #endif MoreMasters (); MoreMasters (); #if 0 /* Intialize SDL, and put up a dialog if we fail */ if ( SDL_Init (0) < 0 ) { #define kErr_OK 1 #define kErr_Text 2 DialogPtr errorDialog; short dummyType; Rect dummyRect; Handle dummyHandle; short itemHit; errorDialog = GetNewDialog (1001, nil, (WindowPtr)-1); DrawDialog (errorDialog); GetDialogItem (errorDialog, kErr_Text, &dummyType, &dummyHandle, &dummyRect); SetDialogItemText (dummyHandle, "\pError Initializing SDL"); SetPort (errorDialog); do { ModalDialog (nil, &itemHit); } while (itemHit != kErr_OK); DisposeDialog (errorDialog); exit (-1); } atexit(cleanup_output); atexit(SDL_Quit); #endif /* Set up SDL's QuickDraw environment */ #if !TARGET_API_MAC_CARBON SDL_InitQuickDraw(&qd); #endif if ( readPreferences (&prefs) ) { if (memcmp (prefs.video_driver_name+1, "DSp", 3) == 0) videodriver = 1; else if (memcmp (prefs.video_driver_name+1, "toolbox", 7) == 0) videodriver = 2; } if ( CommandKeyIsDown() ) { #define kCL_OK 1 #define kCL_Cancel 2 #define kCL_Text 3 #define kCL_File 4 #define kCL_Video 6 DialogPtr commandDialog; short dummyType; Rect dummyRect; Handle dummyHandle; short itemHit; /* Assume that they will change settings, rather than do exhaustive check */ settingsChanged = 1; /* Create dialog and display it */ commandDialog = GetNewDialog (1000, nil, (DialogPtr)-1); SetPort (commandDialog); /* Setup controls */ GetDialogItem (commandDialog, kCL_File, &dummyType, &dummyHandle, &dummyRect); /* MJS */ SetControlValue ((ControlHandle)dummyHandle, prefs.output_to_file ); GetDialogItem (commandDialog, kCL_Text, &dummyType, &dummyHandle, &dummyRect); SetDialogItemText (dummyHandle, prefs.command_line); GetDialogItem (commandDialog, kCL_Video, &dummyType, &dummyHandle, &dummyRect); SetControlValue ((ControlRef)dummyHandle, videodriver); SetDialogDefaultItem (commandDialog, kCL_OK); SetDialogCancelItem (commandDialog, kCL_Cancel); do { ModalDialog(nil, &itemHit); /* wait for user response */ /* Toggle command-line output checkbox */ if ( itemHit == kCL_File ) { GetDialogItem(commandDialog, kCL_File, &dummyType, &dummyHandle, &dummyRect); /* MJS */ SetControlValue((ControlHandle)dummyHandle, !GetControlValue((ControlHandle)dummyHandle) ); } } while (itemHit != kCL_OK && itemHit != kCL_Cancel); /* Get control values, even if they did not change */ GetDialogItem (commandDialog, kCL_Text, &dummyType, &dummyHandle, &dummyRect); /* MJS */ GetDialogItemText (dummyHandle, prefs.command_line); GetDialogItem (commandDialog, kCL_File, &dummyType, &dummyHandle, &dummyRect); /* MJS */ prefs.output_to_file = GetControlValue ((ControlHandle)dummyHandle); GetDialogItem (commandDialog, kCL_Video, &dummyType, &dummyHandle, &dummyRect); videodriver = GetControlValue ((ControlRef)dummyHandle); DisposeDialog (commandDialog); if (itemHit == kCL_Cancel ) { exit (0); } } /* Set pseudo-environment variables for video driver, update prefs */ switch ( videodriver ) { case VIDEO_ID_DRAWSPROCKET: putenv ("SDL_VIDEODRIVER=DSp"); memcpy (prefs.video_driver_name, "\pDSp", 4); break; case VIDEO_ID_TOOLBOX: putenv ("SDL_VIDEODRIVER=toolbox"); memcpy (prefs.video_driver_name, "\ptoolbox", 8); break; } /* Redirect standard I/O to files */ if ( prefs.output_to_file ) { freopen (STDOUT_FILE, "w", stdout); freopen (STDERR_FILE, "w", stderr); } else { fclose (stdout); fclose (stderr); } if (settingsChanged) { /* Save the prefs, even if they might not have changed (but probably did) */ if ( ! writePreferences (&prefs) ) fprintf (stderr, "WARNING: Could not save preferences!\n"); } getCurrentAppName (appNameText); /* check for error here ? */ commandLine = (char*) malloc (appNameText[0] + prefs.command_line[0] + 2); if ( commandLine == NULL ) { exit(-1); } /* Rather than rewrite ParseCommandLine method, let's replace */ /* any spaces in application name with underscores, */ /* so that the app name is only 1 argument */ for (i = 1; i < 1+appNameText[0]; i++) if ( appNameText[i] == ' ' ) appNameText[i] = '_'; /* Copy app name & full command text to command-line C-string */ memcpy (commandLine, appNameText + 1, appNameText[0]); commandLine[appNameText[0]] = ' '; memcpy (commandLine + appNameText[0] + 1, prefs.command_line + 1, prefs.command_line[0]); commandLine[ appNameText[0] + 1 + prefs.command_line[0] ] = '\0'; /* Parse C-string into argv and argc */ nargs = ParseCommandLine (commandLine, NULL); args = (char **)malloc((nargs+1)*(sizeof *args)); if ( args == NULL ) { exit(-1); } ParseCommandLine (commandLine, args); /* Run the main application code */ SDL_main(nargs, args); free (args); free (commandLine); /* Remove useless stdout.txt and stderr.txt */ cleanup_output (); /* Exit cleanly, calling atexit() functions */ exit (0); /* Never reached, but keeps the compiler quiet */ return (0); }