view src/cdrom/macos/SDL_syscdrom_c.h @ 3880:74e828c64315 SDL-1.2

Fixed bug #292 I might be on crack here. It looks like SDL_ConvertMono() in src/audio/SDL_audiocvt.c adds the left and right channels of a stereo stream together, and clamps the new mono channel if it would overflow. Shouldn't it be dividing by 2 to average the two sample points instead of clamping? Otherwise the mono sample point's volume doubles in the conversion. This would also make the conversion faster, as it replaces two branches per sample frame with a bitwise shift. --ryan.
author Sam Lantinga <slouken@libsdl.org>
date Sun, 24 Sep 2006 15:45:37 +0000
parents d910939febfa
children 782fd950bd46 a1b03ba2fcd0
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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
*/
#include "SDL_config.h"

/* This is the MacOS specific header for the SDL CD-ROM API
   Contributed by Matt Slot
 */

/* AppleCD Control calls */
#define kVerifyTheDisc   	  5		/* Returns noErr if there is disc inserted */
#define kEjectTheDisc   	  7		/* Eject disc from drive */
#define kUserEject    		 80		/* Enable/disable the CD-ROM eject button */
#define kReadTOC    		100		/* Extract various TOC information from the disc */
#define kReadQ   			101		/* Extract Q subcode info for the current track */
#define kAudioTrackSearch   103		/* Start playback from the indicated position */
#define kAudioPlay    		104		/* Start playback from the indicated position */
#define kAudioPause    		105		/* Pause/continue the playback */
#define kAudioStop    		106		/* Stop playback at the indicated position */
#define kAudioStatus    	107		/* Return audio play status */
#define kAudioControl    	109		/* Set the output volume for the audio channels */
#define kReadAudioVolume   	112		/* Get the output volume for the audio channels */
#define kSetTrackList   	122		/* Set the track program for the audio CD to play */
#define kGetTrackList   	123		/* Get the track program the audio CD is playing */
#define kGetTrackIndex   	124		/* Get the track index the audio CD is playing */
#define kSetPlayMode   		125		/* Set the audio tracks play mode */
#define kGetPlayMode   		126		/* Get the audio tracks play mode */

/* AppleCD Status calls */
#define kGetDriveType   	 96		/* Get the type of the physical CD-ROM drive */
#define kWhoIsThere    		 97		/* Get a bitmap of SCSI IDs the driver controls */
#define kGetBlockSize    	 98		/* Get current block size of the CD-ROM drive */
	
/* AppleCD other constants */
#define kBlockPosition    	  0		/* Position at the specified logical block number */
#define kAbsMSFPosition    	  1		/* Position at the specified Min/Sec/Frame (in BCD) */
#define kTrackPosition    	  2		/* Position at the specified track number (in BCD) */
#define kIndexPosition    	  3		/* Position at the nth track in program (in BCD) */

#define kMutedPlayMode   	  0		/* Play the audio track with no output */
#define kStereoPlayMode   	  9		/* Play the audio track in normal stereo */

#define kControlFieldMask  	0x0D	/* Bits 3,2,0 in the nibble */
#define kDataTrackMask   	0x04	/* Indicates Data Track */

#define kGetTrackRange    	  1		/* Query TOC for track numbers */
#define kGetLeadOutArea    	  2		/* Query TOC for "Lead Out" end of audio data */
#define kGetTrackEntries   	  3		/* Query TOC for track starts and data types */

#define kStatusPlaying		  0		/* Audio Play operation in progress */
#define kStatusPaused		  1		/* CD-ROM device in Hold Track ("Pause") state */
#define kStatusMuted		  2		/* MUTING-ON operation in progress */
#define kStatusDone			  3		/* Audio Play completed */
#define kStatusError		  4		/* Error occurred during audio play operation */
#define kStatusStopped		  5		/* Audio play operation not requested */

#define kPlayModeSequential	  0		/*  Play tracks in order */
#define kPlayModeShuffled	  1		/* Play tracks randomly */
#define kPlayModeProgrammed   2		/* Use custom playlist */

/* AppleCD Gestalt selectors */
#define kGestaltAudioCDSelector    'aucd'
#define kDriverVersion52   		0x00000520
#define kDriverVersion51   		0x00000510
#define kDriverVersion50   		0x00000500

/* Drive type constants */
#define kDriveAppleCD_SC   				  1
#define kDriveAppleCD_SCPlus_or_150   	  2
#define kDriveAppleCD_300_or_300Plus   	  3

/* Misc constants */
#define kFirstSCSIDevice   	 -33
#define kLastSCSIDevice    	 -40

#if PRAGMA_STRUCT_ALIGN
	#pragma options align=mac68k
#endif

/* AppleCD driver parameter block */
typedef struct CDCntrlParam {
	QElemPtr				qLink;
	short					qType;
	short					ioTrap;
	Ptr						ioCmdAddr;
	IOCompletionUPP			ioCompletion;
	OSErr					ioResult;
	StringPtr				ioNamePtr;
	short					ioVRefNum;
	short					ioCRefNum;
	short					csCode;
	
	union {
		long				longs[6];
		short				words[11];
		unsigned char		bytes[22];
		struct {
			unsigned char	status;
			unsigned char	play;
			unsigned char	control;
			unsigned char	minute;
			unsigned char	second;
			unsigned char	frame;
			} cd;
		} csParam;

	} CDCntrlParam, *CDCntrlParamPtr;

typedef union CDTrackData {
	long				value;			/* Treat as a longword value */
	struct {
		unsigned char	reserved : 4;	/* Unused by AppleCD driver  */
		unsigned char	control : 4;	/* Track flags (data track?) */
		unsigned char	min;			/* Start of track (BCD)      */
		unsigned char	sec;			/* Start of track (BCD)      */
		unsigned char	frame;			/* Start of track (BCD)      */
		} entry;						/* Broken into fields        */
	} CDTrackData, *CDTrackPtr;
	
#if PRAGMA_STRUCT_ALIGN
	#pragma options align=reset
#endif