limit the number of identical sounds playing at once, based on priority ordering (#807)

* Revert "add parallel same-sound limit from DSDA-Doom (#796)"

This reverts commit d7849c8fa7ba4b2c92a1784b92127df267f4e8db.

* first shot at sorting sounds by priority

* fix build

* our S_AdjustSoundParams() already mangles volume into priority

* add/fix comments

* newer same-priority sounds are supposed to stop older ones

* use qsort() instead of undocumented (whoops\!) SDL_qsort()

* back to newer same-priority sounds let older ones finish

* keep the singularity concept alive

* get rid of the lowestpriority concept, we already ordered channels by priority

* keep the "snd_channels = 16" default

* Revert "keep the "snd_channels = 16" default"

This reverts commit 79fc9b3332304aa7cd9f7ac687c46089f1d40918.

* Update s_sound.c

* maintain a stable sort (newer sounds have precedence)

* fix typo/thinko

* fix sort order

* fix comparison function return value

* Update s_sound.c

* last nit-pick (hopefully!)

src/m_menu.c

@@ -3710,6 +3710,7 @@ enum {
   // [FG] uncapped rendering frame rate
   general_uncapped,
   general_vsync,
+  general_stub1,
   general_trans,
   general_transpct,
   general_gamma,
@@ -3717,7 +3718,6 @@ enum {
 
   general_title2,
   general_sndchan,
-  general_parallelsfx,
   general_pitch,
   // [FG] play sounds in full length
   general_fullsnd,
@@ -3789,6 +3789,8 @@ setup_menu_t gen_settings1[] = { // General Settings screen1
   {"Vertical Sync", S_YESNO, m_null, M_X,
    M_Y+ general_vsync*M_SPC, {"use_vsync"}, 0, I_ResetScreen},
 
+  {"", S_SKIP, m_null, M_X, M_Y + general_stub1*M_SPC},
+
   {"Enable predefined translucency", S_YESNO, m_null, M_X,
    M_Y+ general_trans*M_SPC, {"translucency"}, 0, M_Trans},
 
@@ -3806,10 +3808,6 @@ setup_menu_t gen_settings1[] = { // General Settings screen1
   {"Number of Sound Channels", S_NUM|S_PRGWARN, m_null, M_X,
    M_Y + general_sndchan*M_SPC, {"snd_channels"}},
 
-  // [FG] parallel same-sound limit from DSDA-Doom
-  {"Parallel Same-Sound Limit", S_YESNO, m_null, M_X,
-   M_Y + general_parallelsfx*M_SPC, {"parallel_sfx"}},
-
   {"Enable v1.1 Pitch Effects", S_YESNO, m_null, M_X,
    M_Y + general_pitch*M_SPC, {"pitched_sounds"}},
 

src/m_misc.c

@@ -1493,7 +1493,7 @@ default_t defaults[] = {
   { // killough
     "snd_channels",
     (config_t *) &default_numChannels, NULL,
-    {16}, {1, MAX_CHANNELS}, 0, ss_gen, wad_no,
+    {MAX_CHANNELS}, {1, MAX_CHANNELS}, 0, ss_gen, wad_no,
     "number of sound effects handled simultaneously"
   },
 
@@ -2253,28 +2253,6 @@ default_t defaults[] = {
     "1 to play sounds in full length"
   },
 
-  // [FG] parallel same-sound limit
-  {
-    "parallel_sfx",
-    (config_t *) &parallel_sfx, NULL,
-    {0}, {0, 1}, number, ss_gen, wad_no,
-    "1 to enable parallel same-sound limit"
-  },
-
-  {
-    "parallel_sfx_limit",
-    (config_t *) &parallel_sfx_limit, NULL,
-    {2}, {0, 32}, number, ss_none, wad_no,
-    "parallel same-sound limit"
-  },
-
-  {
-    "parallel_sfx_window",
-    (config_t *) &parallel_sfx_window, NULL,
-    {4}, {1, 32}, number, ss_none, wad_no,
-    "parallel same-sound limit window"
-  },
-
   // [FG] music backend
   {
     "midi_player",

src/s_sound.c

@@ -29,6 +29,8 @@
 // killough 3/7/98: modified to allow arbitrary listeners in spy mode
 // killough 5/2/98: reindented, removed useless code, beautified
 
+#include <stdlib.h> // [FG] qsort()
+
 #include "doomstat.h"
 #include "s_sound.h"
 #include "s_musinfo.h" // [crispy] struct musinfo
@@ -228,6 +230,28 @@ static int S_AdjustSoundParams(const mobj_t *listener, const mobj_t *source,
   return *vol > 0;
 }
 
+//
+// S_CompareChannels
+//
+// A comparison function that determines which sound channel should
+// take priority. Can be used with std::sort.
+//
+// Returns true if the first channel should precede the second.
+//
+static int S_CompareChannels(const void *arg_a, const void *arg_b)
+{
+  const channel_t *a = (const channel_t *) arg_a;
+  const channel_t *b = (const channel_t *) arg_b;
+
+  // Note that a higher priority number means lower priority!
+  const int ret = a->priority - b->priority;
+
+  return ret ? ret : (b->idnum - a->idnum);
+}
+
+// How many instances of the same sfx can be playing concurrently
+static const unsigned int max_instances = 3;
+
 //
 // S_getChannel :
 //
@@ -240,8 +264,10 @@ static int S_getChannel(const mobj_t *origin, sfxinfo_t *sfxinfo,
 {
    // channel number to use
    int cnum;
-   int lowestpriority = -1; // haleyjd
-   int lpcnum = -1;
+   int instances = 0;
+
+   // Sort the sound channels by descending priority levels
+   qsort(channels, numChannels, sizeof(channel_t), S_CompareChannels);
 
    // haleyjd 09/28/06: moved this here. If we kill a sound already
    // being played, we can use that channel. There is no need to
@@ -250,82 +276,65 @@ static int S_getChannel(const mobj_t *origin, sfxinfo_t *sfxinfo,
    // kill old sound
    // killough 12/98: replace is_pickup hack with singularity flag
    // haleyjd 06/12/08: only if subchannel matches
-   for(cnum = 0; cnum < numChannels; ++cnum)
+   for (cnum = 0; cnum < numChannels; ++cnum)
    {
-      if(channels[cnum].sfxinfo &&
-         channels[cnum].singularity == singularity &&
-         channels[cnum].origin == origin)
-      {
-         // [FG] looping sounds don't interrupt each other
-         if (channels[cnum].sfxinfo == sfxinfo && channels[cnum].loop && loop)
-           return -1;
+     if (!channels[cnum].sfxinfo)
+       continue;
 
-         S_StopChannel(cnum);
-         break;
-      }
+     // [FG] looping sounds don't interrupt each other
+     if (channels[cnum].sfxinfo == sfxinfo &&
+         channels[cnum].origin == origin &&
+         channels[cnum].loop && loop)
+     {
+       return -1;
+     }
+
+     if (channels[cnum].singularity == singularity &&
+         channels[cnum].origin == origin)
+     {
+       S_StopChannel(cnum);
+       return cnum;
+     }
+
+     // Limit the number of identical sounds playing at once
+     if (channels[cnum].sfxinfo == sfxinfo)
+     {
+       if (++instances >= max_instances)
+       {
+         if (priority < channels[cnum].priority)
+         {
+           S_StopChannel(cnum);
+           return cnum;
+         }
+         else
+         {
+           return -1;
+         }
+       }
+     }
    }
 
    // Find an open channel
-   if(cnum == numChannels)
+   for (cnum = 0; cnum < numChannels; ++cnum)
    {
-      // haleyjd 09/28/06: it isn't necessary to look for playing sounds in
-      // the same singularity class again, as we just did that above. Here
-      // we are looking for an open channel. We will also keep track of the
-      // channel found with the lowest sound priority while doing this.
-      for(cnum = 0; cnum < numChannels && channels[cnum].sfxinfo; ++cnum)
-      {
-         if(channels[cnum].priority > lowestpriority)
-         {
-            lowestpriority = channels[cnum].priority;
-            lpcnum = cnum;
-         }
-      }
+     if (!channels[cnum].sfxinfo)
+       return cnum;
    }
 
    // None available?
-   if(cnum == numChannels)
+   for (cnum = numChannels - 1; cnum >= 0; --cnum)
    {
-      // Look for lower priority
-      // haleyjd: we have stored the channel found with the lowest priority
-      // in the loop above
-      if(priority > lowestpriority)
-         return -1;                  // No lower priority.  Sorry, Charlie.
-      else
-      {
-         S_StopChannel(lpcnum);      // Otherwise, kick out lowest priority.
-         cnum = lpcnum;
-      }
+     // Look for lower priority
+     if (priority < channels[cnum].priority)
+     {
+       S_StopChannel(cnum);
+       return cnum;
+     }
    }
 
-#ifdef RANGECHECK
-   if(cnum >= numChannels)
-      I_Error("S_getChannel: handle %d out of range\n", cnum);
-#endif
-   
-   return cnum;
+   return -1;
 }
 
-// [FG] parallel same-sound limit from DSDA-Doom
-
-boolean parallel_sfx;
-int parallel_sfx_limit;
-int parallel_sfx_window;
-
-static boolean BlockSFX(sfxinfo_t *sfx)
-{
-  if (!parallel_sfx)
-    return false;
-
-  if (gametic - sfx->parallel_tic >= parallel_sfx_window)
-  {
-    sfx->parallel_tic = gametic;
-    sfx->parallel_count = 0;
-  }
-
-  ++sfx->parallel_count;
-
-  return sfx->parallel_count > parallel_sfx_limit;
-}
 
 static void S_StartSoundEx(const mobj_t *origin, int sfx_id, boolean loop)
 {
@@ -392,10 +401,6 @@ static void S_StartSoundEx(const mobj_t *origin, int sfx_id, boolean loop)
          sep = NORM_SEP;
   }
 
-   // [FG] parallel same-sound limit from DSDA-Doom
-   if (BlockSFX(sfx))
-     return;
-
    if(pitched_sounds)
    {
       // hacks to vary the sfx pitches

src/sounds.h

@@ -78,16 +78,8 @@ typedef struct sfxinfo_struct {
 
   // haleyjd 04/23/08: additional caching data
   unsigned int alen;   // length of converted sound pointed to by data
-
-  // [FG] parallel same-sound limit from DSDA-Doom
-  int parallel_tic;
-  int parallel_count;
 } sfxinfo_t;
 
-extern boolean parallel_sfx;
-extern int parallel_sfx_limit;
-extern int parallel_sfx_window;
-
 //
 // MusicInfo struct.
 //