+#endif /* AUDIO_LINUX_IOCTL */
+
+#if defined(PLATFORM_NETBSD)
+static void InitAudioDevice_NetBSD(struct AudioFormatInfo *afmt)
+{
+ audio_info_t a_info;
+ boolean stereo = TRUE;
+
+ AUDIO_INITINFO(&a_info);
+ a_info.play.encoding = AUDIO_ENCODING_LINEAR8;
+ a_info.play.precision = 8;
+ a_info.play.channels = 2;
+ a_info.play.sample_rate = sample_rate;
+ a_info.blocksize = fragment_size;
+
+ afmt->format = AUDIO_FORMAT_U8;
+ afmt->stereo = TRUE;
+
+ if (ioctl(audio.device_fd, AUDIO_SETINFO, &a_info) < 0)
+ {
+ /* try to disable stereo */
+ a_info.play.channels = 1;
+
+ afmt->stereo = FALSE;
+
+ if (ioctl(audio.device_fd, AUDIO_SETINFO, &a_info) < 0)
+ Error(ERR_EXIT_SOUND_SERVER,
+ "cannot set sample rate of /dev/audio -- no sounds");
+ }
+}
+#endif /* PLATFORM_NETBSD */
+
+#if defined(PLATFORM_HPUX)
+static void InitAudioDevice_HPUX(struct AudioFormatInfo *afmt)
+{
+ struct audio_describe ainfo;
+ int audio_ctl;
+
+ audio_ctl = open("/dev/audioCtl", O_WRONLY | O_NDELAY);
+ if (audio_ctl == -1)
+ Error(ERR_EXIT_SOUND_SERVER, "cannot open /dev/audioCtl -- no sounds");
+
+ if (ioctl(audio_ctl, AUDIO_DESCRIBE, &ainfo) == -1)
+ Error(ERR_EXIT_SOUND_SERVER, "no audio info -- no sounds");
+
+ if (ioctl(audio_ctl, AUDIO_SET_DATA_FORMAT, AUDIO_FORMAT_ULAW) == -1)
+ Error(ERR_EXIT_SOUND_SERVER, "ulaw audio not available -- no sounds");
+
+ ioctl(audio_ctl, AUDIO_SET_CHANNELS, 1);
+ ioctl(audio_ctl, AUDIO_SET_SAMPLE_RATE, 8000);
+
+ afmt->format = AUDIO_FORMAT_U8;
+ afmt->stereo = FALSE;
+ afmt->sample_rate = 8000;
+
+ close(audio_ctl);
+}
+#endif /* PLATFORM_HPUX */
+
+static void InitAudioDevice(struct AudioFormatInfo *afmt)
+{
+ afmt->stereo = TRUE;
+ afmt->format = AUDIO_FORMAT_UNKNOWN;
+ afmt->sample_rate = DEFAULT_AUDIO_SAMPLE_RATE;
+ afmt->fragment_size = DEFAULT_AUDIO_FRAGMENT_SIZE;
+
+#if defined(AUDIO_LINUX_IOCTL)
+ InitAudioDevice_Linux(afmt);
+#elif defined(PLATFORM_NETBSD)
+ InitAudioDevice_NetBSD(afmt);
+#elif defined(PLATFORM_HPUX)
+ InitAudioDevice_HPUX(afmt);
+#else
+ /* generic /dev/audio stuff might be placed here */
+#endif
+}
+
+
+/* ------------------------------------------------------------------------- */
+/* functions for communication between main process and sound mixer process */
+/* ------------------------------------------------------------------------- */
+
+static void SendSoundControlToMixerProcess(SoundControl *snd_ctrl)
+{
+ if (IS_CHILD_PROCESS(audio.mixer_pid))
+ return;
+
+ if (write(audio.mixer_pipe[1], snd_ctrl, sizeof(SoundControl)) < 0)
+ {
+ Error(ERR_WARN, "cannot pipe to child process -- no sounds");
+ audio.sound_available = audio.sound_enabled = FALSE;
+ return;
+ }
+}
+
+static void ReadSoundControlFromMainProcess(SoundControl *snd_ctrl)
+{
+ if (IS_PARENT_PROCESS(audio.mixer_pid))
+ return;
+
+ if (read(audio.mixer_pipe[0], snd_ctrl, sizeof(SoundControl))
+ != sizeof(SoundControl))
+ Error(ERR_EXIT_SOUND_SERVER, "broken pipe -- no sounds");
+}
+
+static void WriteReloadInfoToPipe(char *set_name, int type)
+{
+ SoundControl snd_ctrl;
+ TreeInfo *ti = (type == SND_CTRL_RELOAD_SOUNDS ? artwork.snd_current :
+ artwork.mus_current);
+ unsigned long str_size1 = strlen(leveldir_current->fullpath) + 1;
+ unsigned long str_size2 = strlen(ti->basepath) + 1;
+ unsigned long str_size3 = strlen(ti->fullpath) + 1;
+
+ if (IS_CHILD_PROCESS(audio.mixer_pid))
+ return;
+
+ if (leveldir_current == NULL) /* should never happen */
+ Error(ERR_EXIT, "leveldir_current == NULL");
+
+ snd_ctrl.active = FALSE;
+ snd_ctrl.state = type;
+ snd_ctrl.data_len = strlen(set_name) + 1;
+
+ if (write(audio.mixer_pipe[1], &snd_ctrl,
+ sizeof(snd_ctrl)) < 0 ||
+ write(audio.mixer_pipe[1], set_name,
+ snd_ctrl.data_len) < 0 ||
+ write(audio.mixer_pipe[1], leveldir_current,
+ sizeof(TreeInfo)) < 0 ||
+ write(audio.mixer_pipe[1], ti,
+ sizeof(TreeInfo)) < 0 ||
+ write(audio.mixer_pipe[1], &str_size1,
+ sizeof(unsigned long)) < 0 ||
+ write(audio.mixer_pipe[1], &str_size2,
+ sizeof(unsigned long)) < 0 ||
+ write(audio.mixer_pipe[1], &str_size3,
+ sizeof(unsigned long)) < 0 ||
+ write(audio.mixer_pipe[1], leveldir_current->fullpath,
+ str_size1) < 0 ||
+ write(audio.mixer_pipe[1], ti->basepath,
+ str_size2) < 0 ||
+ write(audio.mixer_pipe[1], ti->fullpath,
+ str_size3) < 0)
+ {
+ Error(ERR_WARN, "cannot pipe to child process -- no sounds");
+ audio.sound_available = audio.sound_enabled = FALSE;
+ return;
+ }
+}
+
+static void ReadReloadInfoFromPipe(SoundControl *snd_ctrl)
+{
+ TreeInfo **ti_ptr = ((snd_ctrl->state & SND_CTRL_RELOAD_SOUNDS) ?
+ &artwork.snd_current : &artwork.mus_current);
+ TreeInfo *ti = *ti_ptr;
+ unsigned long str_size1, str_size2, str_size3;
+ static char *set_name = NULL;
+
+ if (set_name)
+ free(set_name);
+
+ set_name = checked_malloc(snd_ctrl->data_len);
+
+ if (leveldir_current == NULL)
+ leveldir_current = checked_calloc(sizeof(TreeInfo));
+ if (ti == NULL)
+ ti = *ti_ptr = checked_calloc(sizeof(TreeInfo));
+ if (leveldir_current->fullpath != NULL)
+ free(leveldir_current->fullpath);
+ if (ti->basepath != NULL)
+ free(ti->basepath);
+ if (ti->fullpath != NULL)
+ free(ti->fullpath);
+
+ if (read(audio.mixer_pipe[0], set_name,
+ snd_ctrl->data_len) != snd_ctrl->data_len ||
+ read(audio.mixer_pipe[0], leveldir_current,
+ sizeof(TreeInfo)) != sizeof(TreeInfo) ||
+ read(audio.mixer_pipe[0], ti,
+ sizeof(TreeInfo)) != sizeof(TreeInfo) ||
+ read(audio.mixer_pipe[0], &str_size1,
+ sizeof(unsigned long)) != sizeof(unsigned long) ||
+ read(audio.mixer_pipe[0], &str_size2,
+ sizeof(unsigned long)) != sizeof(unsigned long) ||
+ read(audio.mixer_pipe[0], &str_size3,
+ sizeof(unsigned long)) != sizeof(unsigned long))
+ Error(ERR_EXIT_SOUND_SERVER, "broken pipe -- no sounds");
+
+ leveldir_current->fullpath = checked_calloc(str_size1);
+ ti->basepath = checked_calloc(str_size2);
+ ti->fullpath = checked_calloc(str_size3);
+
+ if (read(audio.mixer_pipe[0], leveldir_current->fullpath,
+ str_size1) != str_size1 ||
+ read(audio.mixer_pipe[0], ti->basepath,
+ str_size2) != str_size2 ||
+ read(audio.mixer_pipe[0], ti->fullpath,
+ str_size3) != str_size3)
+ Error(ERR_EXIT_SOUND_SERVER, "broken pipe -- no sounds");
+
+ if (snd_ctrl->state & SND_CTRL_RELOAD_SOUNDS)
+ artwork.sounds_set_current = set_name;
+ else
+ artwork.music_set_current = set_name;
+}
+
+#endif /* AUDIO_UNIX_NATIVE */
+
+
+/* ------------------------------------------------------------------------- */
+/* mixer functions */
+/* ------------------------------------------------------------------------- */
+
+void Mixer_InitChannels()
+{
+ int i;
+
+ for(i=0; i<audio.num_channels; i++)
+ mixer[i].active = FALSE;
+ mixer_active_channels = 0;
+}
+
+static void Mixer_PlayChannel(int channel)
+{
+ /* start with inactive channel in case something goes wrong */
+ mixer[channel].active = FALSE;
+
+ if (mixer[channel].type != MUS_TYPE_WAV)
+ return;
+
+ mixer[channel].playing_pos = 0;
+ mixer[channel].playing_starttime = Counter();
+
+#if defined(TARGET_SDL)
+ Mix_Volume(channel, SOUND_MAX_VOLUME);
+ Mix_PlayChannel(channel, mixer[channel].data_ptr,
+ IS_LOOP(mixer[channel]) ? -1 : 0);
+#elif defined(PLATFORM_MSDOS)
+ mixer[channel].voice = allocate_voice((SAMPLE *)mixer[channel].data_ptr);
+ if (mixer[channel].voice < 0)
+ return;
+
+ if (IS_LOOP(mixer[channel]))
+ voice_set_playmode(mixer[channel].voice, PLAYMODE_LOOP);
+
+ voice_set_volume(mixer[channel].voice, mixer[channel].volume);
+ voice_set_pan(mixer[channel].voice, mixer[channel].stereo_position);
+ voice_start(mixer[channel].voice);
+#endif
+
+ mixer[channel].active = TRUE;
+ mixer_active_channels++;
+}
+
+static void Mixer_PlayMusicChannel()
+{
+ Mixer_PlayChannel(audio.music_channel);
+
+#if defined(TARGET_SDL)
+ if (mixer[audio.music_channel].type != MUS_TYPE_WAV)
+ {
+ /* Mix_VolumeMusic() must be called _after_ Mix_PlayMusic() --
+ this looks like a bug in the SDL_mixer library */
+ Mix_PlayMusic(mixer[audio.music_channel].data_ptr, -1);
+ Mix_VolumeMusic(SOUND_MAX_VOLUME);
+ }
+#endif
+}
+
+static void Mixer_StopChannel(int channel)
+{
+#if 0
+#if defined(TARGET_SDL)
+ printf("----------> %d [%d]\n", Mix_Playing(channel), Mix_Playing(0));
+#endif
+#endif
+
+ if (!mixer[channel].active)
+ return;
+
+#if defined(TARGET_SDL)
+ Mix_HaltChannel(channel);
+#elif defined(PLATFORM_MSDOS)
+ voice_set_volume(mixer[channel].voice, 0);
+ deallocate_voice(mixer[channel].voice);
+#endif
+
+ mixer[channel].active = FALSE;
+ mixer_active_channels--;
+}
+
+static void Mixer_StopMusicChannel()
+{
+ Mixer_StopChannel(audio.music_channel);
+
+#if defined(TARGET_SDL)
+ Mix_HaltMusic();
+#endif
+}
+
+static void Mixer_FadeChannel(int channel)
+{
+ if (!mixer[channel].active)
+ return;
+
+ mixer[channel].state |= SND_CTRL_FADE;
+
+#if defined(TARGET_SDL)
+ Mix_FadeOutChannel(channel, SOUND_FADING_INTERVAL);
+#elif defined(PLATFORM_MSDOS)
+ if (voice_check(mixer[channel].voice))
+ voice_ramp_volume(mixer[channel].voice, SOUND_FADING_INTERVAL, 0);
+#endif
+}
+
+static void Mixer_FadeMusicChannel()
+{
+ Mixer_FadeChannel(audio.music_channel);
+
+#if defined(TARGET_SDL)
+ Mix_FadeOutMusic(SOUND_FADING_INTERVAL);
+#endif
+}
+
+static void Mixer_UnFadeChannel(int channel)
+{
+ if (!mixer[channel].active || !IS_FADING(mixer[channel]))
+ return;
+
+ mixer[channel].state &= ~SND_CTRL_FADE;
+ mixer[channel].volume = PSND_MAX_VOLUME;
+
+#if defined(TARGET_SDL)
+ Mix_ExpireChannel(channel, -1);
+ Mix_Volume(channel, SOUND_MAX_VOLUME);
+#elif defined(TARGET_ALLEGRO)
+ voice_stop_volumeramp(mixer[channel].voice);
+ voice_ramp_volume(mixer[channel].voice, SOUND_FADING_INTERVAL,
+ mixer[channel].volume);
+#endif
+}
+
+static void Mixer_InsertSound(SoundControl snd_ctrl)
+{
+ SoundInfo *snd_info;
+ int i, k;
+
+#if 0
+ printf("NEW SOUND %d HAS ARRIVED [%d]\n", snd_ctrl.nr, num_sounds);
+#endif
+
+#if 0
+ printf("%d ACTIVE CHANNELS\n", mixer_active_channels);
+#endif
+
+ if (IS_MUSIC(snd_ctrl))
+ snd_ctrl.nr = snd_ctrl.nr % num_music;
+ else if (snd_ctrl.nr >= num_sounds)
+ return;
+
+ snd_info = (IS_MUSIC(snd_ctrl) ? Music[snd_ctrl.nr] : Sound[snd_ctrl.nr]);
+ if (snd_info == NULL)
+ return;
+
+ /* copy sound sample and format information */
+ snd_ctrl.type = snd_info->type;
+ snd_ctrl.format = snd_info->format;
+ snd_ctrl.data_ptr = snd_info->data_ptr;
+ snd_ctrl.data_len = snd_info->data_len;
+
+ /* play music samples on a dedicated music channel */
+ if (IS_MUSIC(snd_ctrl))
+ {
+ mixer[audio.music_channel] = snd_ctrl;
+ Mixer_PlayMusicChannel();
+
+ return;
+ }
+
+ /* check if sound is already being played (and how often) */
+ for (k=0, i=audio.first_sound_channel; i<audio.num_channels; i++)
+ if (mixer[i].nr == snd_ctrl.nr)
+ k++;
+
+ /* restart loop sounds only if they are just fading out */
+ if (k >= 1 && IS_LOOP(snd_ctrl))
+ {
+ for(i=audio.first_sound_channel; i<audio.num_channels; i++)
+ if (mixer[i].nr == snd_ctrl.nr && IS_FADING(mixer[i]))
+ Mixer_UnFadeChannel(i);
+
+ return;
+ }
+
+ /* don't play sound more than n times simultaneously (with n == 2 for now) */
+ if (k >= 2)
+ {
+ unsigned long playing_current = Counter();
+ int longest = 0, longest_nr = audio.first_sound_channel;
+
+ /* look for oldest equal sound */
+ for(i=audio.first_sound_channel; i<audio.num_channels; i++)
+ {
+ int playing_time = playing_current - mixer[i].playing_starttime;
+ int actual;
+
+ if (!mixer[i].active || mixer[i].nr != snd_ctrl.nr)
+ continue;
+
+#if 1
+ actual = 1000 * playing_time / mixer[i].data_len;
+#else
+ actual = 100 * mixer[i].playing_pos / mixer[i].data_len;
+#endif
+
+ if (actual >= longest)
+ {
+ longest = actual;
+ longest_nr = i;
+ }
+ }
+
+ Mixer_StopChannel(longest_nr);
+ }
+
+ /* If all (non-music) channels are active, stop the channel that has
+ played its sound sample most completely (in percent of the sample
+ length). As we cannot currently get the actual playing position
+ of the channel's sound sample when compiling with the SDL mixer
+ library, we use the current playing time (in milliseconds) instead. */
+
+ if (mixer_active_channels ==
+ audio.num_channels - (mixer[audio.music_channel].active ? 0 : 1))
+ {
+ unsigned long playing_current = Counter();
+ int longest = 0, longest_nr = audio.first_sound_channel;
+
+ for (i=audio.first_sound_channel; i<audio.num_channels; i++)
+ {
+#if 1
+ int playing_time = playing_current - mixer[i].playing_starttime;
+ int actual = 1000 * playing_time / mixer[i].data_len;
+#else
+ int actual = 100 * mixer[i].playing_pos / mixer[i].data_len;
+#endif
+
+ if (!IS_LOOP(mixer[i]) && actual > longest)
+ {
+ longest = actual;
+ longest_nr = i;
+ }
+ }
+
+ Mixer_StopChannel(longest_nr);
+ }
+
+ /* add new sound to mixer */
+ for(i=0; i<audio.num_channels; i++)
+ {
+#if 0
+ printf("CHECKING CHANNEL %d FOR SOUND %d ...\n", i, snd_ctrl.nr);
+#endif
+
+ /*
+ if (!mixer[i].active ||
+ (IS_MUSIC(snd_ctrl) && i == audio.music_channel))
+ */
+ if ((i == audio.music_channel && IS_MUSIC(snd_ctrl)) ||
+ (i != audio.music_channel && !mixer[i].active))
+ {
+#if 0
+ printf("ADDING NEW SOUND %d TO MIXER\n", snd_ctrl.nr);
+#endif
+
+#if 1
+#if defined(AUDIO_UNIX_NATIVE)
+ if (snd_info->data_len == 0)
+ {
+ printf("THIS SHOULD NEVER HAPPEN! [snd_info->data_len == 0]\n");
+ }
+#endif
+#endif
+
+#if 1
+ if (IS_MUSIC(snd_ctrl) && i == audio.music_channel && mixer[i].active)
+ {
+ printf("THIS SHOULD NEVER HAPPEN! [adding music twice]\n");
+
+#if 1
+ Mixer_StopChannel(i);
+#endif
+ }
+#endif
+
+ mixer[i] = snd_ctrl;
+ Mixer_PlayChannel(i);
+
+ break;
+ }
+ }
+}
+
+static void HandleSoundRequest(SoundControl snd_ctrl)
+{
+ int i;
+
+#if defined(AUDIO_UNIX_NATIVE)
+ if (IS_PARENT_PROCESS(audio.mixer_pid))
+ {
+ SendSoundControlToMixerProcess(&snd_ctrl);
+ return;
+ }
+#elif defined(TARGET_SDL)
+ for (i=0; i<audio.num_channels; i++)
+ if (!Mix_Playing(i))
+ Mixer_StopChannel(i);
+#elif defined(TARGET_ALLEGRO)
+ for (i=0; i<audio.num_channels; i++)
+ {
+ if (!mixer[i].active || IS_LOOP(mixer[i]))
+ continue;
+
+ mixer[i].playing_pos = voice_get_position(mixer[i].voice);
+ mixer[i].volume = voice_get_volume(mixer[i].voice);
+
+ /* sound sample has completed playing or was completely faded out */
+ if (mixer[i].playing_pos == -1 || mixer[i].volume == 0)
+ Mixer_StopChannel(i);
+ }
+#endif /* TARGET_ALLEGRO */
+
+ if (IS_RELOADING(snd_ctrl)) /* load new sound or music files */
+ {
+ Mixer_StopMusicChannel();
+ for(i=audio.first_sound_channel; i<audio.num_channels; i++)
+ Mixer_StopChannel(i);
+
+#if defined(AUDIO_UNIX_NATIVE)
+ CloseAudioDevice(&audio.device_fd);
+ ReadReloadInfoFromPipe(&snd_ctrl);
+#endif
+
+ if (snd_ctrl.state & SND_CTRL_RELOAD_SOUNDS)
+ ReloadCustomSounds();
+ else
+ ReloadCustomMusic();
+ }
+ else if (IS_FADING(snd_ctrl)) /* fade out existing sound or music */
+ {
+ if (IS_MUSIC(snd_ctrl))
+ {
+ Mixer_FadeMusicChannel();
+ return;
+ }
+
+ for(i=audio.first_sound_channel; i<audio.num_channels; i++)
+ if (mixer[i].nr == snd_ctrl.nr || ALL_SOUNDS(snd_ctrl))
+ Mixer_FadeChannel(i);
+ }
+ else if (IS_STOPPING(snd_ctrl)) /* stop existing sound or music */
+ {
+ if (IS_MUSIC(snd_ctrl))
+ {
+ Mixer_StopMusicChannel();
+ return;
+ }
+
+ for(i=audio.first_sound_channel; i<audio.num_channels; i++)
+ if (mixer[i].nr == snd_ctrl.nr || ALL_SOUNDS(snd_ctrl))
+ Mixer_StopChannel(i);
+
+#if defined(AUDIO_UNIX_NATIVE)
+ if (!mixer_active_channels)
+ CloseAudioDevice(&audio.device_fd);
+#endif
+ }
+ else if (snd_ctrl.active) /* add new sound to mixer */
+ {
+ Mixer_InsertSound(snd_ctrl);
+ }
+}
+
+void StartMixer(void)
+{
+#if 0
+ SDL_version compile_version;
+ const SDL_version *link_version;
+ MIX_VERSION(&compile_version);
+ printf("compiled with SDL_mixer version: %d.%d.%d\n",
+ compile_version.major,
+ compile_version.minor,
+ compile_version.patch);
+ link_version = Mix_Linked_Version();
+ printf("running with SDL_mixer version: %d.%d.%d\n",
+ link_version->major,
+ link_version->minor,
+ link_version->patch);
+#endif
+
+ if (!audio.sound_available)
+ return;
+
+#if defined(AUDIO_UNIX_NATIVE)
+ if (!ForkAudioProcess())
+ audio.sound_available = FALSE;
+#endif
+}
+
+#if defined(AUDIO_UNIX_NATIVE)
+
+static void CopySampleToMixingBuffer(SoundControl *snd_ctrl,
+ int sample_pos, int sample_size,
+ short *buffer_ptr)
+{
+ void *sample_ptr = snd_ctrl->data_ptr;
+ int i;
+
+ if (snd_ctrl->format == AUDIO_FORMAT_U8)
+ for (i=0; i<sample_size; i++)
+ *buffer_ptr++ =
+ ((short)(((byte *)sample_ptr)[sample_pos + i] ^ 0x80)) << 8;
+ else /* AUDIO_FORMAT_S16 */
+ for (i=0; i<sample_size; i++)
+ *buffer_ptr++ =
+ ((short *)sample_ptr)[sample_pos + i];
+}
+
+#if defined(AUDIO_STREAMING_DSP)
+static void Mixer_Main_DSP()
+{
+ static int stereo_volume[PSND_MAX_LEFT2RIGHT + 1];
+ static boolean stereo_volume_calculated = FALSE;
+ static short premix_first_buffer[SND_BLOCKSIZE];
+ static short premix_left_buffer[SND_BLOCKSIZE];
+ static short premix_right_buffer[SND_BLOCKSIZE];
+ static long premix_last_buffer[SND_BLOCKSIZE];
+ static byte playing_buffer[SND_BLOCKSIZE];
+ boolean stereo;
+ int fragment_size;
+ int sample_bytes;
+ int max_sample_size;
+ int i, j;
+
+ if (!stereo_volume_calculated)
+ {
+ for(i=0; i<=PSND_MAX_LEFT2RIGHT; i++)
+ stereo_volume[i] =
+ (int)sqrt((float)(PSND_MAX_LEFT2RIGHT * PSND_MAX_LEFT2RIGHT - i * i));
+
+ stereo_volume_calculated = TRUE;
+ }
+
+ if (!mixer_active_channels)
+ return;
+
+ if (audio.device_fd < 0)
+ {
+ if ((audio.device_fd = OpenAudioDevice(audio.device_name)) < 0)
+ return;
+
+ InitAudioDevice(&afmt);
+ }
+
+ stereo = afmt.stereo;
+ fragment_size = afmt.fragment_size;
+ sample_bytes = (afmt.format & AUDIO_FORMAT_U8 ? 1 : 2);
+ max_sample_size = fragment_size / ((stereo ? 2 : 1) * sample_bytes);
+
+ /* first clear the last premixing buffer */
+ memset(premix_last_buffer, 0,
+ max_sample_size * (stereo ? 2 : 1) * sizeof(long));
+
+ for(i=0; i<audio.num_channels; i++)
+ {
+ void *sample_ptr;
+ int sample_len;
+ int sample_pos;
+ int sample_size;
+
+ if (!mixer[i].active)
+ continue;
+
+ /* pointer, lenght and actual playing position of sound sample */
+ sample_ptr = mixer[i].data_ptr;
+ sample_len = mixer[i].data_len;
+ sample_pos = mixer[i].playing_pos;
+ sample_size = MIN(max_sample_size, sample_len - sample_pos);
+ mixer[i].playing_pos += sample_size;
+
+ /* copy original sample to first mixing buffer */
+ CopySampleToMixingBuffer(&mixer[i], sample_pos, sample_size,
+ premix_first_buffer);
+
+ /* are we about to restart a looping sound? */
+ if (IS_LOOP(mixer[i]) && sample_size < max_sample_size)
+ {
+ while (sample_size < max_sample_size)
+ {
+ int restarted_sample_size =
+ MIN(max_sample_size - sample_size, sample_len);
+
+ if (mixer[i].format == AUDIO_FORMAT_U8)
+ for (j=0; j<restarted_sample_size; j++)
+ premix_first_buffer[sample_size + j] =
+ ((short)(((byte *)sample_ptr)[j] ^ 0x80)) << 8;
+ else
+ for (j=0; j<restarted_sample_size; j++)
+ premix_first_buffer[sample_size + j] =
+ ((short *)sample_ptr)[j];
+
+ mixer[i].playing_pos = restarted_sample_size;
+ sample_size += restarted_sample_size;
+ }
+ }
+
+ /* decrease volume if sound is fading out */
+ if (IS_FADING(mixer[i]) &&
+ mixer[i].volume >= SOUND_FADING_VOLUME_THRESHOLD)
+ mixer[i].volume -= SOUND_FADING_VOLUME_STEP;
+
+ /* adjust volume of actual sound sample */
+ if (mixer[i].volume != PSND_MAX_VOLUME)
+ for(j=0; j<sample_size; j++)
+ premix_first_buffer[j] =
+ (mixer[i].volume * (long)premix_first_buffer[j])
+ >> PSND_MAX_VOLUME_BITS;
+
+ /* fill the last mixing buffer with stereo or mono sound */
+ if (stereo)
+ {
+ int middle_pos = PSND_MAX_LEFT2RIGHT / 2;
+ int left_volume = stereo_volume[middle_pos + mixer[i].stereo_position];
+ int right_volume= stereo_volume[middle_pos - mixer[i].stereo_position];
+
+ for(j=0; j<sample_size; j++)
+ {
+ premix_left_buffer[j] =
+ (left_volume * premix_first_buffer[j])
+ >> PSND_MAX_LEFT2RIGHT_BITS;
+ premix_right_buffer[j] =
+ (right_volume * premix_first_buffer[j])
+ >> PSND_MAX_LEFT2RIGHT_BITS;
+
+ premix_last_buffer[2 * j + 0] += premix_left_buffer[j];
+ premix_last_buffer[2 * j + 1] += premix_right_buffer[j];
+ }
+ }
+ else
+ {
+ for(j=0; j<sample_size; j++)
+ premix_last_buffer[j] += premix_first_buffer[j];
+ }
+
+ /* delete completed sound entries from the mixer */
+ if (mixer[i].playing_pos >= mixer[i].data_len)
+ {
+ if (IS_LOOP(mixer[i]))
+ mixer[i].playing_pos = 0;
+ else
+ Mixer_StopChannel(i);
+ }
+ else if (mixer[i].volume <= SOUND_FADING_VOLUME_THRESHOLD)
+ Mixer_StopChannel(i);
+ }
+
+ /* prepare final playing buffer according to system audio format */
+ for(i=0; i<max_sample_size * (stereo ? 2 : 1); i++)
+ {
+ /* cut off at 17 bit value */
+ if (premix_last_buffer[i] < -65535)
+ premix_last_buffer[i] = -65535;
+ else if (premix_last_buffer[i] > 65535)
+ premix_last_buffer[i] = 65535;
+
+ /* shift to 16 bit value */
+ premix_last_buffer[i] >>= 1;
+
+ if (afmt.format & AUDIO_FORMAT_U8)
+ {
+ playing_buffer[i] = (premix_last_buffer[i] >> 8) ^ 0x80;
+ }
+ else if (afmt.format & AUDIO_FORMAT_LE) /* 16 bit */
+ {
+ playing_buffer[2 * i + 0] = premix_last_buffer[i] & 0xff;
+ playing_buffer[2 * i + 1] = premix_last_buffer[i] >> 8;
+ }
+ else /* big endian */
+ {
+ playing_buffer[2 * i + 0] = premix_last_buffer[i] >> 8;
+ playing_buffer[2 * i + 1] = premix_last_buffer[i] & 0xff;
+ }
+ }
+
+ /* finally play the sound fragment */
+ write(audio.device_fd, playing_buffer, fragment_size);
+
+ if (!mixer_active_channels)
+ CloseAudioDevice(&audio.device_fd);
+}
+
+#else /* !AUDIO_STREAMING_DSP */
+
+static int Mixer_Main_SimpleAudio(SoundControl snd_ctrl)
+{
+ static short premix_first_buffer[SND_BLOCKSIZE];
+ static byte playing_buffer[SND_BLOCKSIZE];
+ int max_sample_size = SND_BLOCKSIZE;
+ void *sample_ptr;
+ int sample_len;
+ int sample_pos;
+ int sample_size;
+ int i, j;
+
+ i = 1;
+
+ /* pointer, lenght and actual playing position of sound sample */
+ sample_ptr = mixer[i].data_ptr;
+ sample_len = mixer[i].data_len;
+ sample_pos = mixer[i].playing_pos;
+ sample_size = MIN(max_sample_size, sample_len - sample_pos);
+ mixer[i].playing_pos += sample_size;
+
+ /* copy original sample to first mixing buffer */
+ CopySampleToMixingBuffer(&mixer[i], sample_pos, sample_size,
+ premix_first_buffer);
+
+ /* adjust volume of actual sound sample */
+ if (mixer[i].volume != PSND_MAX_VOLUME)
+ for(j=0; j<sample_size; j++)
+ premix_first_buffer[j] =
+ (mixer[i].volume * (long)premix_first_buffer[j])
+ >> PSND_MAX_VOLUME_BITS;
+
+ /* might be needed for u-law /dev/audio */
+#if 0
+ for(j=0; j<sample_size; j++)
+ playing_buffer[j] =
+ linear_to_ulaw(premix_first_buffer[j]);
+#endif
+
+ /* delete completed sound entries from the mixer */
+ if (mixer[i].playing_pos >= mixer[i].data_len)
+ Mixer_StopChannel(i);
+
+ for(i=0; i<sample_size; i++)
+ playing_buffer[i] = (premix_first_buffer[i] >> 8) ^ 0x80;
+
+ /* finally play the sound fragment */
+ write(audio.device_fd, playing_buffer, sample_size);
+
+ return sample_size;
+}
+#endif /* !AUDIO_STREAMING_DSP */