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--- soundenginealsa.cxx.orig Mon Sep 4 19:47:37 2006
+++ soundenginealsa.cxx Wed Sep 6 04:43:37 2006
@@ -38,85 +38,20 @@
complexfeed(0),
enginefeed(0),
activefeed(0),
- handle(0),
- periodsz(0),
batchsize(0),
framelag(lag),
lpfilter(0.0)
{
- /* Open PCM device for playback. */
- int rc = snd_pcm_open(&handle, "default", SND_PCM_STREAM_PLAYBACK, 0);
- if (rc < 0)
- {
- fprintf(stderr, "unable to open pcm device: %s\n", snd_strerror(rc));
- return;
- }
- snd_pcm_hw_params_t *params=0;
-
- /* Allocate a hardware parameters object. */
- snd_pcm_hw_params_alloca(¶ms);
- /* Fill it in with default values. */
- snd_pcm_hw_params_any(handle, params);
- /* Set the desired hardware parameters. */
- /* Interleaved mode */
- snd_pcm_hw_params_set_access(handle, params, SND_PCM_ACCESS_RW_INTERLEAVED);
- /* Signed 16-bit little-endian format */
- snd_pcm_hw_params_set_format(handle, params, SND_PCM_FORMAT_S16_LE);
- /* Two channels (stereo) */
- snd_pcm_hw_params_set_channels(handle, params, 2);
- /* 44100 bits/second sampling rate (CD quality) */
- const unsigned int cd_rate = 44100;
- unsigned int playback_sampling_rate = cd_rate;
- int dir=-1; // round down actual rate, please.
- snd_pcm_hw_params_set_rate_near(handle, params, &playback_sampling_rate, &dir);
- if (playback_sampling_rate != cd_rate)
- {
- fprintf
- (
- stderr,
- "Asked for %dHz playback rate, but got %dHz\n",
- cd_rate,
- playback_sampling_rate
- );
- }
-
- snd_pcm_uframes_t frames = framelag;
- snd_pcm_hw_params_set_period_size_near(handle, params, &frames, &dir);
-
- /* Write the parameters to the driver */
- rc = snd_pcm_hw_params(handle, params);
- if (rc < 0)
- {
- fprintf(stderr, "unable to set hw parameters: %s\n", snd_strerror(rc));
- return;
- }
- snd_pcm_hw_params_get_period_size(params, &periodsz, &dir);
- batchsize = (int) ceilf(framelag / (float) periodsz);
- fprintf(stderr,"soundenginealsa.cxx: requested period %d, got period %d, use batchsize %d\n", framelag, (int) periodsz, batchsize);
-
- simplefeed = new SoundFeedSimple(periodsz);
- complexfeed = new SoundFeedComplex(periodsz);
- modulatedfeed = new SoundFeedModulated(periodsz);
- enginefeed = new SoundFeedEngine(periodsz);
- activefeed = simplefeed;
- opened = true;
}
SoundEngineAlsa::~SoundEngineAlsa()
{
- if (opened)
- {
- fprintf(stderr,"Closing down SoundEngineAlsa\n");
- snd_pcm_drain(handle);
- snd_pcm_close(handle);
- }
}
void SoundEngineAlsa::Play(const std::string &fname, int delay)
{
- activefeed->Paste(fname, delay);
}
@@ -173,58 +108,7 @@
float SoundEngineAlsa::Sustain(void)
{
- if (!activefeed)
return 0.0;
- snd_pcm_sframes_t delay;
- int avail = snd_pcm_avail_update(handle);
- int rc = snd_pcm_delay(handle, &delay);
- if (rc<0)
- snd_strerror(rc);
- if (rc==-EPIPE)
- fprintf(stderr,"soundenginealsa.cxx: EPIPE\n");
- else
- assert(!rc);
-
- // We can only trust pcm_delay if the state is running.
- snd_pcm_state_t pcm_state = snd_pcm_state(handle);
- if (pcm_state != SND_PCM_STATE_RUNNING || delay<0)
- {
- delay=0;
- if (pcm_state == SND_PCM_STATE_XRUN)
- snd_pcm_prepare(handle);
- }
-
-#if 0
- if (delay<0)
- fprintf(stderr,"delay=%d, avail=%d, periodsz=%d\n", delay, avail, periodsz);
-#else
- (void) avail;
-#endif
-
- float fractiondone = activefeed->FractionDone(delay);
-
- if (delay < framelag)
- {
- int cnt = batchsize;
- short *data = activefeed->Get(cnt);
- if (cnt)
- {
- assert(data);
- if (lpfilter>0.01)
- low_pass_filter(data, cnt*periodsz, lpfilter);
- rc = snd_pcm_writei(handle, data, cnt*periodsz);
- assert(rc == -EPIPE || rc >= 0);
- if (rc == -EPIPE)
- {
- snd_pcm_prepare(handle);
- fprintf(stderr,"Underrrun!\n");
- }
- else
- if (rc != (int) (cnt*periodsz))
- fprintf(stderr, "short write, wrote %d frames instead of %d\n", rc, (int) periodsz);
- }
- }
- return fractiondone;
}
clipmap_t SoundClip::clips;
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