MacFormat 1999 Spring/macformat-077.iso/Shareware Plus/Development/SpriteWorld 2.2/SpriteWorld files/Utils/SWSounds.c

Text File | 1999-02-08 | 16.7 KB | 665 lines | [TEXT/CWIE]

///--------------------------------------------------------------------------------------
// SWSounds.c
//
// Created 11/13/96
///--------------------------------------------------------------------------------------

#include "SWSounds.h"


#define kNonZeroValue            1        // used to avoid a bug in the Sound Manager


typedef struct ChanStruct
{
    SndChannelPtr    channelP;            // Pointer to the sound channel
    short            curSoundID;            // The ID of the sound currently playing in this channel.
    short            volume;                // current volume for this channel
    short            stereoPos;            // stereo position of this channel
    Boolean            isDone;                // Is this channel done playing the last sound?
    Boolean            isAvailable;        // Used by SetChannelAvailability.
} ChanStruct, *ChanStructPtr;


short        gNumSounds;
short        gNumChannels;                // Number of sound channels
ChanStruct    *gChanArray;                // Channel array that's allocated at run-time
Handle        *gSoundHArray;                // Array of handles to all our sounds
Boolean        gStereoMode = true;            // Whether to use stereo or mono
long        gOldSystemSoundVolume = -1;    // used by SaveSystemVolume and RestoreSystemVolume

SndCallBackUPP    gSoundCallBackUPP;        // Needed for PPC


///--------------------------------------------------------------------------------------
// IsNewSoundManagerInstalled
///--------------------------------------------------------------------------------------

Boolean IsNewSoundManagerInstalled( void )
{
    NumVersion    theVersion;
    void        *trap1;
    void        *trap2;
    Boolean        installed;

    installed = FALSE;
    trap1 = (void *)GetToolTrapAddress(_SoundDispatch);    // SndSoundManagerVersion Trap
    trap2 = (void *)GetToolTrapAddress(_Unimplemented);    // Unimplemented Trap

    if (trap1 != trap2)
    {
        theVersion = SndSoundManagerVersion();
        if (theVersion.majorRev >= 3)
        {
            installed = TRUE;
        }
    }

    return installed;
}


///--------------------------------------------------------------------------------------
// SetSystemVolume
///--------------------------------------------------------------------------------------

void    SetSystemVolume(short volume)
{
    if (volume < 0)
        volume = 0;
    else if (volume > 7)
        volume = 7;

        // Convert from 0-7 to 0-256
    volume = (256 * volume + 6) / 7;    // the + 6 avoids rounding errors

        // We set the left and right speaker volume to the same value.
    SetDefaultOutputVolume((long)((long)volume << 16L | (volume & 0xFFFF)));
}


///--------------------------------------------------------------------------------------
// GetSystemVolume
///--------------------------------------------------------------------------------------

void    GetSystemVolume(short *volume)
{
    short    leftVol, rightVol, combinedVol, result;
    long    totalVol;

        // We set the left and right speaker volume to the same value.
    GetDefaultOutputVolume(&totalVol);

    rightVol = totalVol >> 16L;
    leftVol = totalVol & 0xFFFF;

        // Get the combined volume of the left and right speakers
    combinedVol = (rightVol + leftVol) / 2;

        // Convert from 0-256 to 0-7
    result = (combinedVol * 7) / 256;
    if (result == 0 && combinedVol > 0)        // Any value above 0 has volume
        result = 1;

    *volume = result;
}


///--------------------------------------------------------------------------------------
// SaveSystemVolume
///--------------------------------------------------------------------------------------

void    SaveSystemVolume( void )
{
    GetDefaultOutputVolume(&gOldSystemSoundVolume);
}


///--------------------------------------------------------------------------------------
// RestoreSystemVolume
///--------------------------------------------------------------------------------------

void    RestoreSystemVolume( void )
{
        // We set the left and right speaker volume to the same value.
    if (gOldSystemSoundVolume != -1)
        SetDefaultOutputVolume(gOldSystemSoundVolume);
}


///--------------------------------------------------------------------------------------
// CreateSoundChannels
///--------------------------------------------------------------------------------------

OSErr    CreateSoundChannels(short numChannels)
{
    Size            arraySize;
    short            n;
    OSErr            err = noErr;

    gSoundCallBackUPP = NewSndCallBackProc(SoundCallBack);

    gNumChannels = numChannels;
    if (numChannels <= 0)
        return -1;

        // Allocate memory for gChanArray
    arraySize = (Size)numChannels * sizeof(ChanStruct);
    gChanArray = (ChanStruct *)NewPtrClear(arraySize);
    err = MemError();


    if (err == noErr)
    {
            // Create the sound channels
        for (n=0; n < numChannels; n++)
        {
            err = SndNewChannel(&gChanArray[n].channelP, sampledSynth, initMono, gSoundCallBackUPP);
            gChanArray[n].channelP->userInfo = SetCurrentA5();
            gChanArray[n].isDone = true;
            gChanArray[n].curSoundID = -1;
            gChanArray[n].volume = kFullVolume;
            gChanArray[n].stereoPos = 0;
            gChanArray[n].isAvailable = true;

            if (err)
                break;
        }

        if (err != noErr) // Dispose what we created
        {
            while (n)
            {
                SndDisposeChannel(gChanArray[--n].channelP, true);
            }

            DisposePtr((Ptr)gChanArray);
        }
    }

    if (err != noErr)
    {
            // Get rid of our UPPs
        DisposeRoutineDescriptor( gSoundCallBackUPP );
    }

    return err;
}


///--------------------------------------------------------------------------------------
// DisposeSoundChannels
///--------------------------------------------------------------------------------------

void    DisposeSoundChannels( void )
{
    while (gNumChannels)
    {
        SndDisposeChannel(gChanArray[--gNumChannels].channelP, true);
    }

    DisposePtr((Ptr)gChanArray);

        // Get rid of our UPPs
    DisposeRoutineDescriptor( gSoundCallBackUPP );
}


///--------------------------------------------------------------------------------------
// LoadSounds
///--------------------------------------------------------------------------------------

OSErr    LoadSounds( short startResID, short numSounds )
{
    short        index;
    Size        arraySize;
    OSErr        err = noErr;

    gNumSounds = numSounds;

        // Allocate memory for gSoundHArray
    arraySize = (Size)numSounds * sizeof(Handle);
    gSoundHArray = (Handle *)NewPtrClear(arraySize);
    err = MemError();

    if (err == noErr)
    {
            // Load the sounds
        for (index = 0; index < numSounds && err != memFullErr; index++)
        {
            gSoundHArray[index] = GetResource('snd ', startResID + index);

            if (gSoundHArray[index] != NULL)
            {
                HLock(gSoundHArray[index]);
            }
            else
            {
                    // If old err was a memory error, don't replace it with resNotFound
                if (err == noErr || err == resNotFound)
                    err = ResError() ? ResError() : resNotFound;
            }
        }
    }

    return err;
}


///--------------------------------------------------------------------------------------
// DisposeSounds
///--------------------------------------------------------------------------------------

void    DisposeSounds( void )
{
    short    index;

    for (index = 0; index < gNumSounds; index++)
    {
        ReleaseResource(gSoundHArray[index]);
    }

    DisposePtr((Ptr)gSoundHArray);

}


///--------------------------------------------------------------------------------------
// PlaySound - starts playing a sound in the appropriate channel
///--------------------------------------------------------------------------------------

void    PlaySound(
    short soundID,
    short channelNum,
    PlayType playType)
{
    PlaySound2(soundID, channelNum, playType, 256, 0, k22khz, false);
}


///--------------------------------------------------------------------------------------
// PlaySound2 - starts playing a sound in the appropriate channel
///--------------------------------------------------------------------------------------

void    PlaySound2(
    short soundID,
    short channelNum,
    PlayType playType,
    short volume,
    short stereoPosition,
    UnsignedFixed rate,
    Boolean doLoopingSound)
{
    #pragma        unused(rate, doLoopingSound)

    if (soundID < 0 || soundID >= gNumSounds || gSoundHArray[soundID] == NULL)
        return;

    channelNum = FindChannel(soundID, channelNum, playType);

    SetChannelVolume(channelNum, volume);
    SetStereoPosition(channelNum, stereoPosition);
    PlayMySound(soundID, channelNum);
}


///--------------------------------------------------------------------------------------
// FindChannel - used by PlaySound2
///--------------------------------------------------------------------------------------

short    FindChannel(short soundID, short channelNum, PlayType playType)
{
    Boolean        allChannelsAreBusy;
    short        emptyChannelNum;
    short        n;

    if (channelNum < 0 || channelNum >= gNumChannels)
        channelNum = 0;


    if (playType == kPlaySoundInChannel)
    {
        return channelNum;
    }
    else if (playType == kReplaceSameSound)
    {
        for (n=0; n < gNumChannels; n++)    // Look for our sound in all channels
        {
            if (gChanArray[n].curSoundID == soundID)
            {
                return n;
            }
        }
    }

        // The following code is executed if playType is kFindEmptyChannel or if
        // playType was kReplaceSameSound and the sound was not found in any channel.


        // Determine if all channels are busy
    allChannelsAreBusy = true;
    for (n=0; n < gNumChannels; n++)
    {
        if (gChanArray[n].isDone && gChanArray[n].isAvailable)
        {
            allChannelsAreBusy = false;
            emptyChannelNum = n;
            break;
        }
    }


    if (gChanArray[channelNum].isDone)
    {
        return channelNum;        // The requested channel is free
    }
    else if (allChannelsAreBusy)
    {
            // First search all other channels for our sound
        for (n=0; n < gNumChannels; n++)
        {
            if (gChanArray[n].curSoundID == soundID)
            {
                return n;
            }
        }

            // If none are found, return the requested channel
        return channelNum;
    }
    else
    {
        return emptyChannelNum;        // Return an empty channel
    }
}


///--------------------------------------------------------------------------------------
// PlayMySound - called by PlaySound
///--------------------------------------------------------------------------------------

void    PlayMySound(short soundID, short channelNum)
{
    SndCommand    theCommand;

        // Stop any sound already playing in this channel
    StopChannel(channelNum);

        // Play the sound
    gChanArray[channelNum].isDone = false;
    gChanArray[channelNum].curSoundID = soundID;
    SndPlay(gChanArray[channelNum].channelP, (SndListHandle)gSoundHArray[soundID], true);

        // Install the callBack
    theCommand.cmd = callBackCmd;
    theCommand.param1 = kNonZeroValue;
    theCommand.param2 = channelNum;
    SndDoCommand(gChanArray[channelNum].channelP, &theCommand, false);
}


///--------------------------------------------------------------------------------------
// StopSound
///--------------------------------------------------------------------------------------

void    StopSound(short soundID)
{
    short n;

    if (soundID < 0 || soundID >= gNumSounds)
        return;

    for (n=0; n < gNumChannels; n++)
    {
        if (gChanArray[n].curSoundID == soundID)
        {
            StopChannel(n);
        }
    }
}


///--------------------------------------------------------------------------------------
// StopChannel
///--------------------------------------------------------------------------------------

void    StopChannel(short channelNum)
{
    SndCommand    theCommand;

    if (channelNum < 0 || channelNum >= gNumChannels)
        return;

        // Stop the sound already playing in this channel
    if (!gChanArray[channelNum].isDone)
    {
        theCommand.cmd = quietCmd;
        SndDoImmediate(gChanArray[channelNum].channelP, &theCommand);
        theCommand.cmd = flushCmd;
        SndDoImmediate(gChanArray[channelNum].channelP, &theCommand);
        gChanArray[channelNum].isDone = true;
        gChanArray[channelNum].curSoundID = -1;
    }
}


///--------------------------------------------------------------------------------------
// SetChannelVolume
///--------------------------------------------------------------------------------------

void    SetChannelVolume(short channelNum, short newVolume)
{
    if (channelNum < 0 || channelNum >= gNumChannels)
        return;

    if (gChanArray[channelNum].volume != newVolume)
    {
        SetVolumeAndStereoPosition(channelNum, newVolume, gChanArray[channelNum].stereoPos);
    }
}


///--------------------------------------------------------------------------------------
// SetStereoPosition
///--------------------------------------------------------------------------------------

void    SetStereoPosition(short channelNum, short stereoPosition)
{
    if (channelNum < 0 || channelNum >= gNumChannels)
        return;

    if (gChanArray[channelNum].stereoPos != stereoPosition)
    {
        SetVolumeAndStereoPosition(channelNum, gChanArray[channelNum].volume, stereoPosition);
    }
}


///--------------------------------------------------------------------------------------
// SetVolumeAndStereoPosition - used internally.
///--------------------------------------------------------------------------------------

void    SetVolumeAndStereoPosition(short channelNum, short newVolume, short stereoPosition)
{
    short            leftVolume, rightVolume, stereoOffset;
    SndCommand        theCommand;

    if (channelNum < 0 || channelNum >= gNumChannels)
        return;

    if (newVolume < 0)
        newVolume = 0;

    if (stereoPosition < -256)
        stereoPosition = -256;
    else if (stereoPosition > 256)
        stereoPosition = 256;

    gChanArray[channelNum].volume = newVolume;
    gChanArray[channelNum].stereoPos = stereoPosition;

    if (gStereoMode == true)
    {
            // Calculate stereoOffset based on stereoPosition and the current volume
        stereoOffset = (newVolume * stereoPosition) / 256;

        leftVolume = newVolume - stereoOffset;
        rightVolume = newVolume + stereoOffset;
    }
    else
    {
            // Mono sound
        leftVolume = newVolume;
        rightVolume = newVolume;
    }

        // Issue the command
    theCommand.param1 = 0;
    theCommand.param2 = (long)((long)rightVolume << 16L | (leftVolume & 0xFFFF));
    theCommand.cmd = volumeCmd;
    SndDoImmediate(gChanArray[channelNum].channelP, &theCommand);
}


///--------------------------------------------------------------------------------------
// SetChannelAvailability
///--------------------------------------------------------------------------------------

void    SetChannelAvailability(short channelNum, Boolean isAvailable)
{
    if (channelNum < 0 || channelNum >= gNumChannels)
        return;

    gChanArray[channelNum].isAvailable = isAvailable;
}


///--------------------------------------------------------------------------------------
// SetStereoMode
///--------------------------------------------------------------------------------------

void    SetStereoMode(Boolean mode)
{
    short    n;

    gStereoMode = mode;

        // Update all channels for the current mode
    for (n = 0; n < gNumChannels; n++)
    {
        SetVolumeAndStereoPosition(n, gChanArray[n].volume, gChanArray[n].stereoPos);
    }
}


///--------------------------------------------------------------------------------------
//   GetStereoPositionOfSprite
///--------------------------------------------------------------------------------------

short    GetStereoPositionOfSprite(SpritePtr srcSpriteP, Rect *destRectP)
{
    short    col, stereoPos;

    col = srcSpriteP->destFrameRect.left + SW_RECT_WIDTH(srcSpriteP->destFrameRect) / 2;

    stereoPos = GetStereoPositionOfColumn(col, destRectP);

    return stereoPos;
}


///--------------------------------------------------------------------------------------
//   GetStereoPositionOfColumn
///--------------------------------------------------------------------------------------

short    GetStereoPositionOfColumn(long col, Rect *backRectP)
{
    Rect    backRect = *backRectP;
    long    screenMidCol;
    short    offset, stereoPos;

        // Make sure the left side starts at 0
    if (backRect.left != 0)
    {
        offset = backRect.left;
        backRect.left -= offset;
        backRect.right -= offset;
        col -= offset;
    }

    screenMidCol = backRect.right / 2;

        // Fix col if out of bounds
    if (col < 0)
        col = 0;
    else if (col > backRect.right)
        col = backRect.right;

        // Calculate it
    col -= screenMidCol;
    stereoPos = (col * 256) / screenMidCol;

    return stereoPos;
}


///--------------------------------------------------------------------------------------
// FindSound - searches all channels for soundID. Returns channel number, or -1.
///--------------------------------------------------------------------------------------

short    FindSound(short soundID)
{
    short        channel;
    Boolean        foundSound;

    foundSound = false;
    for (channel = 0; channel < gNumChannels; channel++)
    {
        if (gChanArray[channel].curSoundID == soundID)
        {
            foundSound = true;
            break;
        }
    }

    if (foundSound)
        return channel;
    else
        return -1;
}


///--------------------------------------------------------------------------------------
// SoundCallBack - called when a channel is done playing a sound
///--------------------------------------------------------------------------------------

pascal void SoundCallBack(SndChannelPtr theChannel, SndCommand *theCommand)
{
    short        channelNum;
    long        saveA5;

#if SW_PPC
    #pragma unused(saveA5, theChannel)
#else
    saveA5 = SetA5(theChannel->userInfo);
#endif

        // We check for kNonZeroValue to avoid a bug in some versions of the Sound Manager.
    if (theCommand->param1 == kNonZeroValue)
    {
        channelNum = theCommand->param2;

        if (channelNum >= 0 && channelNum < gNumChannels)
        {
            gChanArray[channelNum].isDone = true;
            gChanArray[channelNum].curSoundID = -1;
        }
    }


#if !SW_PPC
    SetA5(saveA5);
#endif
}