Audio.cpp

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#include "Audio.h"
#include "Game.h"
#include <vector>

int SOUND_CAP=100;
int index=0;
vector<string> soundlist (SOUND_CAP);


struct sample {
    Uint8 *data;
    Uint32 dpos;
    Uint32 dlen;
        SDL_AudioCVT cvt;
} sounds[100];

Audio::Audio()
{
        if(SDL_Init(SDL_INIT_AUDIO) == -1)
        {
                //
        }

        extern void mixaudio(void *unused, Uint8 *stream, int len);
    SDL_AudioSpec fmt;

    /* Set 16-bit stereo audio at 22Khz */
    fmt.freq = 22050;
    fmt.format = AUDIO_S16;
    fmt.channels = 2;
    fmt.samples = 512;        /* A good value for games */
    fmt.callback = mixaudio;
    fmt.userdata = NULL;

        if ( SDL_OpenAudio(&fmt, NULL) < 0 ) {
        fprintf(stderr, "Unable to open audio: %s\n", SDL_GetError());
        exit(1);
    }
    SDL_PauseAudio(0);
}

int Audio::LoadAudio(std::string name, string location, bool play_on_start, int play_count)
{
        //Declare the audio file and Initialize

        //SDL_Init(SDL_AUDIO);
         int index;
    SDL_AudioSpec wave;
    Uint8 *data;
    Uint32 dlen;
    SDL_AudioCVT cvt;




        //From Documentation
        /* Look for an empty (or finished) sound slot */
    for ( index=0; index<SOUND_CAP; ++index ) {
        if ( sounds[index].dpos == sounds[index].dlen )
                {
            break;
        }
    }
    if ( index == SOUND_CAP )
        return -1;

    /* Load the sound file and convert it to 16-bit stereo at 22kHz */
    if ( SDL_LoadWAV(location.c_str(), &wave, &data, &dlen) == NULL ) {
        fprintf(stderr, "Couldn't load %s: %s\n", location.c_str(), SDL_GetError());
        return -1;
    }
    SDL_BuildAudioCVT(&cvt, wave.format, wave.channels, wave.freq,
                            AUDIO_S16,   2,             22050);

    cvt.buf = (Uint8*) malloc(dlen*cvt.len_mult);
    memcpy(cvt.buf, data, dlen);
    cvt.len = dlen;
    SDL_ConvertAudio(&cvt);
    SDL_FreeWAV(data);

                   if ( sounds[index].data ) {
        free(sounds[index].data);
    }

        
        sounds[index].cvt=cvt;

        return index;

}



void Audio::play(int index)
{
        SDL_AudioCVT cvt=sounds[index].cvt;
        //play an audio file

           if ( sounds[index].data ) {
        free(sounds[index].data);
    }
    SDL_LockAudio();
    sounds[index].data = cvt.buf;
    sounds[index].dlen = cvt.len_cvt;
    sounds[index].dpos = 0;
    SDL_UnlockAudio();
}

void Audio::stop(int index)
{
        SDL_AudioCVT cvt=sounds[index].cvt;

        SDL_LockAudio();
    sounds[index].data = cvt.buf;
    sounds[index].dlen = cvt.len_cvt;
    sounds[index].dpos = cvt.len;
    SDL_UnlockAudio();
}

void Audio::stopAll() 
{
        SDL_CloseAudio();
}

void create_tone( void *userdata, Uint8 *stream, int len ) {
  static double angle = 0.0 ;
  int i = 0 ;
  fprintf( stderr, "Filling %d\n", len ) ;
  for(i=0;i<len;i++) {
    *stream++ = 255*cos(angle) ; 
    angle += 3.14159/100 ; 
    if( angle > 2.0*3.14159 ) {
      angle -= 2.0*3.14159 ;
    }
  }
}

void Audio::tone()
{
        SDL_Surface *screen;
  SDL_Event event;
  int done = 0;
 
  /* Audio Setup */
  SDL_AudioSpec *desired, *obtained;
  SDL_AudioSpec *hardware_spec;
 
  desired = (SDL_AudioSpec*)malloc(sizeof(SDL_AudioSpec));
  obtained = (SDL_AudioSpec*)malloc(sizeof(SDL_AudioSpec));
 
 
  desired->freq=22050;
  desired->format=AUDIO_S16LSB;
  desired->channels=0;
  desired->samples=8192;
  desired->callback=create_tone;
  desired->userdata=NULL;
 
  SDL_Init(SDL_INIT_AUDIO);

  //Open Audio Device

}

void mixaudio(void *unused, Uint8 *stream, int len)
{
    int i;
    Uint32 amount;

    for ( i=0; i<SOUND_CAP; ++i ) {
        amount = (sounds[i].dlen-sounds[i].dpos);
        if ( amount > len ) {
            amount = len;
        }
        SDL_MixAudio(stream, &sounds[i].data[sounds[i].dpos], amount, SDL_MIX_MAXVOLUME);
        sounds[i].dpos += amount;
    }
}