Glypha3/Source/Sound.c

//============================================================================
//----------------------------------------------------------------------------
//									Sound.c
//----------------------------------------------------------------------------
//============================================================================

// This file handles all sound routines.  It handles 2 concurrent sound<6E>
// channels allowing 2 sounds to be played simultaneously.  It also handles<65>
// a system of priorites whereby you can ensure that "important" sounds don't<>
// get cut off by "lesser" sounds.  In that there are 2 channels however,<2C>
// "lesser" sounds are not discounted outright - both channels are considered<65>
// to determine if one of the channels is not playing at all (priority = 0) or<6F>
// playing a sound of an even lesser priority.  Make sense?


#include <Sound.h>
#include "Externs.h"


#define kMaxSounds				17			// Number of sounds to load.
#define	kBaseBufferSoundID		1000		// ID of first sound (assumed sequential).
#define kSoundDone				913			// Just a number I chose.
#define kSoundDone2				749			// Just a number I chose.


void PlaySound1 (short, short);
void PlaySound2 (short, short);
pascal void ExternalCallBack (SndChannelPtr, SndCommand *);
pascal void ExternalCallBack2 (SndChannelPtr, SndCommand *);
void LoadAllSounds (void);
OSErr LoadBufferSounds (void);
OSErr DumpBufferSounds (void);
OSErr OpenSoundChannel (void);
OSErr CloseSoundChannel (void);


SndCallBackUPP		externalCallBackUPP, externalCallBackUPP2;
SndChannelPtr		externalChannel, externalChannel2;
Ptr					theSoundData[kMaxSounds];
short				externalPriority, externalPriority2;
Boolean				channelOpen, soundOn;


//==============================================================  Functions
//--------------------------------------------------------------  PlaySound1
// This function takes a sound ID and a priority, and forces that sound to 
// play through channel 1 - and saves the priority globally.  As well, a 
// callback command is queues up in channel 1.

void PlaySound1 (short soundID, short priority)
{
	SndCommand	theCommand;
	OSErr		theErr;
	
	theCommand.cmd = flushCmd;			// Send 1st a flushCmd to clear the sound queue.
	theCommand.param1 = 0;
	theCommand.param2 = 0L;
	theErr = SndDoImmediate(externalChannel, &theCommand);
	
	theCommand.cmd = quietCmd;			// Send quietCmd to stop any current sound.
	theCommand.param1 = 0;
	theCommand.param2 = 0L;
	theErr = SndDoImmediate(externalChannel, &theCommand);
	
	externalPriority = priority;		// Copy priority to global variable.
	
	theCommand.cmd = bufferCmd;			// Then, send a bufferCmd to channel 1.
	theCommand.param1 = 0;				// The sound played will be soundID.
	theCommand.param2 = (long)(theSoundData[soundID]);
	theErr = SndDoImmediate(externalChannel, &theCommand);
	
	theCommand.cmd = callBackCmd;		// Lastly, queue up a callBackCmd to notify us<75>
	theCommand.param1 = kSoundDone;		// when the sound has finished playing.
	theCommand.param2 = SetCurrentA5();
	theErr = SndDoCommand(externalChannel, &theCommand, TRUE);
}

//--------------------------------------------------------------  PlaySound2
// This function is identical to the above function except that it handles<65>
// playing sounds through channel 2.

void PlaySound2 (short soundID, short priority)
{
	SndCommand	theCommand;
	OSErr		theErr;
	
	theCommand.cmd = flushCmd;			// Send 1st a flushCmd to clear the sound queue.
	theCommand.param1 = 0;
	theCommand.param2 = 0L;
	theErr = SndDoImmediate(externalChannel2, &theCommand);
	
	theCommand.cmd = quietCmd;			// Send quietCmd to stop any current sound.
	theCommand.param1 = 0;
	theCommand.param2 = 0L;
	theErr = SndDoImmediate(externalChannel2, &theCommand);
	
	externalPriority2 = priority;		// Copy priority to global variable.
	
	theCommand.cmd = bufferCmd;			// Then, send a bufferCmd to channel 1.
	theCommand.param1 = 0;				// The sound played will be soundID.
	theCommand.param2 = (long)(theSoundData[soundID]);
	theErr = SndDoImmediate(externalChannel2, &theCommand);
	
	theCommand.cmd = callBackCmd;		// L