multivoc.c

An interactive water fountain. A realistic water source in your pocket with full control. Contro

            {
                MV_CallBackFunc(voice->callbackval);
            }
        }
    }

    return MV_MixPage;
}


/*---------------------------------------------------------------------
   Function: MV_GetNextVOCBlock

   Interperate the information of a VOC format sound file.
---------------------------------------------------------------------*/

static playbackstatus MV_GetNextVOCBlock(VoiceNode *voice)
{
    char *ptr;
    int32_t blocktype;
    int32_t lastblocktype;
    uint32_t blocklength = 0;
    uint32_t samplespeed = 0;
    uint32_t tc = 0;
    int32_t packtype;
    int32_t voicemode;
    int32_t done;
    unsigned       BitsPerSample;
    unsigned       Channels;
    unsigned       Format;

    if (voice->BlockLength > 0)
    {
        voice->position    -= voice->length;
        voice->sound       += voice->length >> 16;
        if (voice->bits == 16)
        {
            voice->sound += voice->length >> 16;
        }
        voice->length       = min(voice->BlockLength, 0x8000);
        voice->BlockLength -= voice->length;
        voice->length     <<= 16;
        return(KeepPlaying);
    }

    if ((voice->length > 0) && (voice->LoopEnd != NULL) && (voice->LoopStart != NULL))
    {
        voice->BlockLength  = voice->LoopSize;
        voice->sound        = voice->LoopStart;
        voice->position     = 0;
        voice->length       = min(voice->BlockLength, 0x8000);
        voice->BlockLength -= voice->length;
        voice->length     <<= 16;
        return(KeepPlaying);
    }

    ptr = (char *)voice->NextBlock;

    voice->Playing = TRUE;

    voicemode = 0;
    lastblocktype = 0;
    packtype = 0;

    done = FALSE;
    while (!done)
    {
        // Stop playing if we get a NULL pointer
        if (ptr == NULL)
        {
            voice->Playing = FALSE;
            done = TRUE;
            break;
        }

        blocktype = (int32_t)*ptr;
        blocklength = (*(uint32_t *)(ptr + 1)) & 0x00ffffff;
        ptr += 4;

        switch (blocktype)
        {
        case 0 :
            // End of data
            if ((voice->LoopStart == NULL) || ((uint32_t *)voice->LoopStart >= (uint32_t *)(ptr - 4)))
            {
                voice->Playing = FALSE;
                done = TRUE;
            }
            else
            {
                voice->BlockLength  = (char*)(ptr - 4) - voice->LoopStart;
                voice->sound        = voice->LoopStart;
                voice->position     = 0;
                voice->length       = min(voice->BlockLength, 0x8000);
                voice->BlockLength -= voice->length;
                voice->length     <<= 16;
                return(KeepPlaying);
            }
            break;

        case 1 :
            // Sound data block
            voice->bits  = 8;
            if (lastblocktype != 8)
            {
                tc = (uint32_t)*ptr << 8;
                packtype = *(ptr + 1);
            }

            ptr += 2;
            blocklength -= 2;

            samplespeed = 256000000L / (65536 - tc);

            // Skip packed or stereo data
            if ((packtype != 0) || (voicemode != 0))
            {
                ptr += blocklength;
            }
            else
            {
                done = TRUE;
            }
            voicemode = 0;
            break;

        case 2 :
            // Sound continuation block
            samplespeed = voice->SamplingRate;
            done = TRUE;
            break;

        case 3 :
            // Silence
            // Not implimented.
            ptr += blocklength;
            break;

        case 4 :
            // Marker
            // Not implimented.
            ptr += blocklength;
            break;

        case 5 :
            // ASCII string
            // Not implimented.
            ptr += blocklength;
            break;

        case 6 :
            // Repeat begin
            if (voice->LoopEnd == NULL)
            {
                voice->LoopCount = *(uint16_t *)ptr;
                voice->LoopStart = (char *)(ptr + blocklength);
            }
            ptr += blocklength;
            break;

        case 7 :
            // Repeat end
            ptr += blocklength;
            if (lastblocktype == 6)
            {
                voice->LoopCount = 0;
            }
            else
            {
                if ((voice->LoopCount > 0) && (voice->LoopStart != NULL))
                {
                    ptr = (char *)voice->LoopStart;
                    if (voice->LoopCount < 0xffff)
                    {
                        voice->LoopCount--;
                        if (voice->LoopCount == 0)
                        {
                            voice->LoopStart = NULL;
                        }
                    }
                }
            }
            break;

        case 8 :
            // Extended block
            voice->bits  = 8;
            tc = *(uint16_t *)ptr;
            packtype = *(ptr + 2);
            voicemode = *(ptr + 3);
            ptr += blocklength;
            break;

        case 9 :
            // New sound data block
            samplespeed = *(uint32_t *)ptr;
            BitsPerSample = (unsigned)*(ptr + 4);
            Channels = (unsigned)*(ptr + 5);
            Format = (unsigned)*(uint16_t *)(ptr + 6);

            if ((BitsPerSample == 8) && (Channels == 1) && (Format == VOC_8BIT))
            {
                ptr         += 12;
                blocklength -= 12;
                voice->bits  = 8;
                done         = TRUE;
            }
            else if ((BitsPerSample == 16) && (Channels == 1) && (Format == VOC_16BIT))
            {
                ptr         += 12;
                blocklength -= 12;
                voice->bits  = 16;
                done         = TRUE;
            }
            else
            {
                ptr += blocklength;
            }
            break;

        default :
            // Unknown data.  Probably not a VOC file.
            voice->Playing = FALSE;
            done = TRUE;
            break;
        }

        lastblocktype = blocktype;
    }

    if (voice->Playing)
    {
        voice->NextBlock    = (char *)(ptr + blocklength);
        voice->sound        = (char *)ptr;

        voice->SamplingRate = samplespeed;
        voice->RateScale    = (voice->SamplingRate * voice->PitchScale) / MV_MixRate;

        // Multiply by MixBufferSize - 1
        voice->FixedPointBufferSize = (voice->RateScale * MixBufferSize) -
                                      voice->RateScale;

        if (voice->LoopEnd != NULL)
        {
            if (blocklength > (uintptr_t)voice->LoopEnd)
            {
                blocklength = (uintptr_t)voice->LoopEnd;
            }
            else
            {
                voice->LoopEnd = (char *)blocklength;
            }

            voice->LoopStart = voice->sound + (uintptr_t)voice->LoopStart;
            voice->LoopEnd   = voice->sound + (uintptr_t)voice->LoopEnd;
            voice->LoopSize  = voice->LoopEnd - voice->LoopStart;
        }

        if (voice->bits == 16)
        {
            blocklength /= 2;
        }

        voice->position     = 0;
        voice->length       = min(blocklength, 0x8000);
        voice->BlockLength  = blocklength - voice->length;
        voice->length     <<= 16;

        MV_SetVoiceMixMode(voice);

        return(KeepPlaying);
    }

    return(NoMoreData);
}


/*---------------------------------------------------------------------
   Function: MV_GetNextDemandFeedBlock

   Controls playback of demand fed data.
---------------------------------------------------------------------*/

playbackstatus MV_GetNextDemandFeedBlock(VoiceNode *voice)
{
    if (voice->BlockLength > 0)
    {
        voice->position    -= voice->length;
        voice->sound       += voice->length >> 16;
        voice->length       = min(voice->BlockLength, 0x8000);
        voice->BlockLength -= voice->length;
        voice->length     <<= 16;

        return(KeepPlaying);
    }

    if (voice->DemandFeed == NULL)
    {
        return(NoMoreData);
    }

    voice->position     = 0;
    (voice->DemandFeed)(&voice->sound, &voice->BlockLength);
    voice->length       = min(voice->BlockLength, 0x8000);
    voice->BlockLength -= voice->length;
    voice->length     <<= 16;

    if ((voice->length > 0) && (voice->sound != NULL))
    {
        return(KeepPlaying);
    }
    return(NoMoreData);
}


/*---------------------------------------------------------------------
   Function: MV_GetNextRawBlock

   Controls playback of demand fed data.
---------------------------------------------------------------------*/

playbackstatus MV_GetNextRawBlock(VoiceNode *voice)
{
    if (voice->BlockLength <= 0)
    {
        if (voice->LoopStart == NULL)
        {
            voice->Playing = FALSE;
            return(NoMoreData);
        }

        voice->BlockLength = voice->LoopSize;
        voice->NextBlock   = voice->LoopStart;
        voice->length = 0;
        voice->position = 0;
    }

    voice->sound        = voice->NextBlock;
    voice->position    -= voice->length;
    voice->length       = min(voice->BlockLength, 0x8000);
    voice->NextBlock   += voice->length;
    if (voice->bits == 16)
    {
        voice->NextBlock += voice->length;
    }
    voice->BlockLength -= voice->length;
    voice->length     <<= 16;

    return(KeepPlaying);
}


/*---------------------------------------------------------------------
   Function: MV_GetNextWAVBlock

   Controls playback of demand fed data.
---------------------------------------------------------------------*/

playbackstatus MV_GetNextWAVBlock(VoiceNode *voice)
{
    if (voice->BlockLength <= 0)
    {
        if (voice->LoopStart == NULL)
        {
            voice->Playing = FALSE;
            return(NoMoreData);
        }

        voice->BlockLength = voice->LoopSize;
        voice->NextBlock   = voice->LoopStart;
        voice->length      = 0;
        voice->position    = 0;
    }

    voice->sound        = voice->NextBlock;
    voice->position    -= voice->length;
    voice->length       = min(voice->BlockLength, 0x8000);
    voice->NextBlock   += voice->length;
    if (voice->bits == 16)
    {
        voice->NextBlock += voice->length;
    }
    voice->BlockLength -= voice->length;
    voice->length     <<= 16;

    return(KeepPlaying);
}

/*---------------------------------------------------------------------
   Function: MV_GetNextOGGBlock

   Controls playback of demand fed data.
---------------------------------------------------------------------*/

void downsample(char *ptr,int32_t size,int32_t factor)
{
    int16_t *pti=(int16_t *)ptr;int32_t i,j,sum;

    for (i=0;i<size>>factor;i++)
    {
        sum=0;
        for (j=0;j<1<<factor;j++)sum+=pti[(i<<factor)+j];
        pti[i]=sum>>factor;
    }
}

playbackstatus MV_GetNextOGGBlock(VoiceNode *voice)
{
    int32_t sz;
    int32_t size=0;
    int32_t section,result;

//    initprintf("_%d %d, %d\n",voice->callbackval,voice->position,voice->BlockLength);
    if (voice->BlockLength <= 0)
    {
        if (voice->LoopStart == NULL)
        {
//            initprintf("END %d\n",voice->callbackval);
            voice->Playing = FALSE;
            return(NoMoreData);
        }
//        initprintf("repeat 2\n");

        voice->BlockLength = voice->LoopSize;
        voice->length      = 0;
        voice->position    = 0;
        ov_pcm_seek(&voice->OGGstream.oggStream,0);
    }

    voice->position    -= voice->length;
    sz=voice->length    = min(voice->BlockLength, 0x8000);
    voice->BlockLength -= voice->length;
    voice->length     <<= 16;

    sz<<=voice->downsample+1;
    while (size<sz)
    {
        result=ov_read(&voice->OGGstream.oggStream,voice->bufsnd+(size>>voice->downsample),sz-size,0,2,1,&section);
        if (result> 0)
        {
            downsample(voice->bufsnd+(size>>voice->downsample),result,voice->downsample);
            size+=result;
        }
        else if (result==0)
        {
//           initprintf("!repeat %d\n",voice->callbackval);
            voice->BlockLength=0;
            voice->length=size<<16;break;
        }
        else
        {
            initprintf("#%d\n",result);
            break;
        }
    }
    voice->sound=voice->bufsnd;

    return(KeepPlaying);
}

/*---------------------------------------------------------------------
   Function: MV_ServiceRecord

   Starts recording of the waiting buffer.
---------------------------------------------------------------------*/
#if 0
static void MV_ServiceRecord(void)
{
    if (MV_RecordFunc)
    {
        MV_RecordFunc(MV_MixBuffer[ 0 ] + MV_MixPage * MixBufferSize, MixBufferSize);
    }

    // Toggle which buffer we'll mix next
    MV_MixPage++;
    if (MV_MixPage >= NumberOfBuffers)
    {
        MV_MixPage = 0;
    }
}
#endif

/*---------------------------------------------------------------------
   Function: MV_GetVoice

   Locates the voice with the specified handle.
---------------------------------------------------------------------*/

VoiceNode *MV_GetVoice(int32_t handle)
{
    VoiceNode *voice;
    unsigned  flags;

    flags = DisableInterrupts();

    for (voice = VoiceList.next; voice != &VoiceList; voice = voice->next)
    {
        if (handle == voice->handle)
        {
            break;
        }
    }

    RestoreInterrupts(flags);

    if (voice == &VoiceList)
    {
        MV_SetErrorCode(MV_VoiceNotFound);
        voice = NULL;
    }

    return(voice);
}


/*---------------------------------------------------------------------
   Function: MV_VoicePlaying