[sound] Move most spacialization fields out of channel_t

More shrinkage. It turned out the mixer uses the phase fields, so they
couldn't be removed, but even at 192kHz, +/- 127 samples produces
sufficient phase separation for a 21cm head (which is, actually, pretty
big: mine is about 15cm across), but that change can come later.

The ambient sound loading has been removed from snd_channels because 1)
it doesn't work for nq, 2) it should never have been there in the first
place (it belongs in the client, but that needs some more API).

include/snd_internal.h

@@ -229,10 +229,7 @@ struct channel_s {
 	unsigned    end;			//!< end time in global paintsamples
 	unsigned    pos;			//!< sample position in sfx
 	unsigned    looping;		//!< where to loop, -1 = no looping
-	vec3_t      origin;			//!< origin of sound effect
-	vec_t       dist_mult;		//!< distance multiplier (attenuation/clip)
 	int         pause;			//!< don't update the channel at all
-	float       volume;			//!< 0-1 overall channel volume
 	int         phase;			//!< phase shift between l-r in samples
 	int         oldphase;		//!< phase shift between l-r in samples
 	/** signal between main program and mixer thread that the channel is to be
@@ -340,6 +337,8 @@ extern	int			snd_total_channels;	//!< number of active channels
 */
 channel_t *SND_AllocChannel (snd_t *snd);
 
+void SND_ChannelSetVolume (channel_t *chan, float volume);
+
 /** Stop a channel from playing.
 	\param snd		sound system state
 	\param chan the channel to stop

libs/audio/renderer/snd_channels.c

@@ -60,9 +60,16 @@ typedef struct entchan_s {
 	int         channel;	// per-entity sound channel
 } entchan_t;
 
+typedef struct spacial_s {
+	vec3_t      origin;			//!< origin of sound effect
+	vec_t       dist_mult;		//!< distance multiplier (attenuation/clip)
+	float       volume;			//!< 0-1 overall channel volume
+} spacial_t;
+
 int             snd_total_channels;
 channel_t       snd_channels[MAX_CHANNELS];
 static entchan_t snd_entity_channels[MAX_CHANNELS];
+static spacial_t snd_spacialization[MAX_CHANNELS];
 static int      snd_free_channels[MAX_CHANNELS];
 static int      snd_num_free_channels;
 /* Dynamic channels are (usually) short sound bytes, never looped. They do not
@@ -347,14 +354,6 @@ s_playvol_f (void *_snd)
 static void
 s_channels_gamedir (int phase, void *_snd)
 {
-	//FIXME for some reason, a gamedir change causes semi-random
-	//"already released" cache errors. fortunatly, servers don't change
-	//gamedir often, so I'll put this in the too-hard basket for now.
-	//XXX FIXME set ambient sounds
-	//if (phase) {
-	//	ambient_sfx[AMBIENT_WATER] = SND_PrecacheSound (snd, "ambience/water1.wav");
-	//	ambient_sfx[AMBIENT_SKY] = SND_PrecacheSound (snd, "ambience/wind2.wav");
-	//}
 }
 
 void
@@ -442,8 +441,10 @@ s_updateAmbientSounds (snd_t *snd, const byte *ambient_sound_level)
 			 ambient_channel++) {
 			chan = ambient_channels[ambient_channel];
 			if (chan) {
-				chan->volume = 0;
+				int         chan_ind = chan - snd_channels;
-				chan->leftvol = chan->rightvol = chan->volume;
+				spacial_t  *spacial = &snd_spacialization[chan_ind];
+				spacial->volume = 0;
+				chan->leftvol = chan->rightvol = spacial->volume;
 			}
 		}
 		return;
@@ -474,23 +475,26 @@ s_updateAmbientSounds (snd_t *snd, const byte *ambient_sound_level)
 		// sfx will be written to chan->sfx later to ensure mixer doesn't use
 		// channel prematurely.
 
+		int         chan_ind = chan - snd_channels;
+		spacial_t  *spacial = &snd_spacialization[chan_ind];
+
 		vol = ambient_level * ambient_sound_level[ambient_channel] * (1/255.0);
 		if (vol < 8/255.0)
 			vol = 0;
 
 		// don't adjust volume too fast
 		float       fade = ambient_fade * (1/255.0);
-		if (chan->volume < vol) {
+		if (spacial->volume < vol) {
-			chan->volume += *snd_render_data.host_frametime * fade;
+			spacial->volume += *snd_render_data.host_frametime * fade;
-			if (chan->volume > vol)
+			if (spacial->volume > vol)
-				chan->volume = vol;
+				spacial->volume = vol;
-		} else if (chan->volume > vol) {
+		} else if (spacial->volume > vol) {
-			chan->volume -= *snd_render_data.host_frametime * fade;
+			spacial->volume -= *snd_render_data.host_frametime * fade;
-			if (chan->volume < vol)
+			if (spacial->volume < vol)
-				chan->volume = vol;
+				spacial->volume = vol;
 		}
 
-		chan->leftvol = chan->rightvol = chan->volume;
+		chan->leftvol = chan->rightvol = spacial->volume;
 		chan->sfx = sfx;
 	}
 }
@@ -506,19 +510,21 @@ s_spatialize (snd_t *snd, channel_t *ch)
 	// prepare to lerp from prev to next phase
 	ch->oldphase = ch->phase;
 
+	spacial_t  *spacial = &snd_spacialization[chan_ind];
+
 	// anything coming from the view entity will always be full volume
 	if (!snd_render_data.viewentity
 		|| snd_entity_channels[chan_ind].id == *snd_render_data.viewentity) {
-		ch->leftvol = ch->volume;
+		ch->leftvol = spacial->volume;
-		ch->rightvol = ch->volume;
+		ch->rightvol = spacial->volume;
 		ch->phase = 0;
 		return;
 	}
 	// calculate stereo seperation and distance attenuation
 
-	VectorSubtract (ch->origin, listener_origin, source_vec);
+	VectorSubtract (spacial->origin, listener_origin, source_vec);
 
-	dist = VectorNormalize (source_vec) * ch->dist_mult;
+	dist = VectorNormalize (source_vec) * spacial->dist_mult;
 
 	dot = DotProduct (listener_right, source_vec);
 	if (snd_swapchannelside)
@@ -536,12 +542,12 @@ s_spatialize (snd_t *snd, channel_t *ch)
 
 	// add in distance effect
 	scale = (1.0 - dist) * rscale;
-	ch->rightvol = ch->volume * scale;
+	ch->rightvol = spacial->volume * scale;
 	if (ch->rightvol < 0)
 		ch->rightvol = 0;
 
 	scale = (1.0 - dist) * lscale;
-	ch->leftvol = ch->volume * scale;
+	ch->leftvol = spacial->volume * scale;
 	if (ch->leftvol < 0)
 		ch->leftvol = 0;
 
@@ -656,9 +662,10 @@ SND_StartSound (snd_t *snd, int entnum, int entchannel, sfx_t *sfx,
 
 	int         chan_ind = target_chan - snd_channels;
 	// spatialize
-	VectorCopy (origin, target_chan->origin);
+	spacial_t  *spacial = &snd_spacialization[chan_ind];
-	target_chan->dist_mult = attenuation / sound_nominal_clip_dist;
+	VectorCopy (origin, spacial->origin);
-	target_chan->volume = vol;
+	spacial->dist_mult = attenuation / sound_nominal_clip_dist;
+	spacial->volume = vol;
 	snd_entity_channels[chan_ind] = (entchan_t) {
 		.id = entnum,
 		.channel = entchannel,
@@ -737,9 +744,10 @@ SND_StaticSound (snd_t *snd, sfx_t *sfx, vec4f_t origin, float vol,
 	if (!(osfx = sfx->open (sfx)))
 		return;
 
-	VectorCopy (origin, ss->origin);
+	spacial_t  *spacial = &snd_spacialization[ss_ind];
-	ss->volume = vol;
+	VectorCopy (origin, spacial->origin);
-	ss->dist_mult = attenuation / sound_nominal_clip_dist;
+	spacial->volume = vol;
+	spacial->dist_mult = attenuation / sound_nominal_clip_dist;
 	ss->end = 0;
 
 	s_spatialize (snd, ss);
@@ -771,3 +779,11 @@ SND_LocalSound (snd_t *snd, const char *sound)
 		viewent = *snd_render_data.viewentity;
 	SND_StartSound (snd, viewent, -1, sfx, (vec4f_t) {0, 0, 0, 1}, 1, 1);
 }
+
+void
+SND_ChannelSetVolume (channel_t *chan, float volume)
+{
+	int         chan_ind = chan - snd_channels;
+	snd_spacialization[chan_ind].volume = volume;
+	chan->leftvol = chan->rightvol = volume;
+}

libs/audio/renderer/snd_dma.c

@@ -522,8 +522,7 @@ s_channel_get_state (channel_t *chan)
 static void
 s_channel_set_volume (channel_t *chan, float volume)
 {
-	chan->volume = volume;
+	SND_ChannelSetVolume (chan, volume);
-	chan->leftvol = chan->rightvol = chan->volume;
 }
 
 static void