/**
* Callback used to provide data to the audio subsystem.
*
* @param userdata N/A
* @param stream Output stream
* @param len Length of data to be placed in the output stream
*/
void audioCallback (void * userdata, unsigned char * stream, int len) {
(void)userdata;
int count;
if (!music_paused) {
// Read the next portion of music into the audio stream
#if defined(USE_MODPLUG)
if (musicFile) ModPlug_Read(musicFile, stream, len);
#elif defined(USE_XMP)
if (xmp_get_player(xmpC, XMP_PLAYER_STATE) == XMP_STATE_PLAYING)
xmp_play_buffer(xmpC, stream, len, 0);
#endif
}
for (count = 0; count < 32; count++) {
if (sounds[count].data && (sounds[count].position >= 0)) {
// Add the next portion of the sound clip to the audio stream
if (len < sounds[count].length - sounds[count].position) {
// Play as much of the clip as possible
SDL_MixAudio(stream,
sounds[count].data + sounds[count].position, len,
soundsVolume * SDL_MIX_MAXVOLUME / MAX_VOLUME);
sounds[count].position += len;
} else {
// Play the remainder of the clip
SDL_MixAudio(stream,
sounds[count].data + sounds[count].position,
sounds[count].length - sounds[count].position,
soundsVolume * SDL_MIX_MAXVOLUME / MAX_VOLUME);
sounds[count].position = -1;
}
}
}
return;
}
static int S_XMP_CodecReadStream (snd_stream_t *stream, int bytes, void *buffer)
{
int r;
/* xmp_play_buffer() requires libxmp >= 4.1. it will write
* native-endian pcm data to the buffer. if the data write
* is partial, the rest of the buffer will be zero-filled.
* the last param is the number that the current sequence of
* the song will be looped at max. */
r = xmp_play_buffer((xmp_context)stream->priv, buffer, bytes, 1);
if (r == 0) {
return bytes;
}
if (r == -XMP_END) {
Con_DPrintf("XMP EOF\n");
return 0;
}
return -1;
}
static void fill_audio(void *udata, Uint8 *stream, int len)
{
if (xmp_play_buffer((xmp_context)udata, stream, len, 0) < 0)
playing = 0;
}
