Changed volume attenuation calculation to match popular EMU devices, run

time polyphony modification, MOD LFO to volume was inverted, some bug fixes.
2024-11-27 14:32:12 +00:00 · 2005-06-08 03:51:13 +00:00 · 2005-06-08 03:51:13 +00:00 · 37d805cb0f
commit 37d805cb0f
parent 1f987a539e
10 changed files with 147 additions and 67 deletions
--- a/fluidsynth/ChangeLog
+++ b/fluidsynth/ChangeLog
@ -1,3 +1,34 @@
+2005-06-07    <jgreen@users.sourceforge.net>
+
+        * Applied Sean Bolton's DSSI patch (SB patch) which adds the ability to
+	  change polyphony at runtime and fixes a bug (see below).
+	* README-OSX: Update from Ebrahim Mayat for OSX Panther.
+	* include/fluidsynth/synth.h: Sean Bolton's DSSI patch adds two new
+	  functions fluid_synth_set_polyphony and fluid_synth_get_polyphony.
+	* src/fluid_conv.c: Centibel to amplitude conversion now follows
+	  EMU 8k/10k which is contrary to SoundFont specification (TiMidity++
+	  used as an example).
+	* src/fluid_conv.h: FLUID_CB_POWER_FACTOR defined for the centibel->amp
+	  conversion table equation.
+	* src/fluid_defsfont.c (load_pgen): Fixed 'use of cast expressions as
+	  lvalues is deprecated' warning by casting the value being assigned
+	  instead of the variable assigned to and removed code warrior
+	  specific code to work around this.
+	  (load_igen): Same as for load_pgen.
+	* src/fluid_synth.c: SB patch - uses synth->polyphony instead of
+	  synth->nvoice when iterating over the synth's voices.
+	  (fluid_synth_update_polyphony): SB patch (new) - runtime update
+	  (fluid_synth_set_polyphony): SB patch (new)
+	  (fluid_synth_get_polyphony): SB patch (new)
+	  (fluid_synth_nwrite_float): SB patch - fixes bug where the use of
+	  arbitrary values of the 'len' parameter was broken.
+	* src/fluid_voice.c (fluid_voice_write): modlfo_to_vol (modulation LFO
+	  to volume) was being calculated inverted (should be negative
+	  attenuation, gain, for a positive rise in LFO).
+	  (fluid_voice_noteoff): Updated centibel to amplitude conversion
+	  used when voice off during attack to use the new
+	  FLUID_CB_POWER_FACTOR.
+
 2004-11-11    <jgreen@users.sourceforge.net>

 	* README-OSX: Update from Ebrahim Mayat.
@ -1223,4 +1254,3 @@
 	select between alsa, oss, midishare, directx, ...

 	* configure.in: preparing for the first pre-release, version 0.0.1
-
--- a/fluidsynth/README-OSX
+++ b/fluidsynth/README-OSX
@ -1,11 +1,11 @@
-Compiling fluidsynth-1.0.5 on Mac OS X.3.5
+Compiling fluidsynth-1.0.5 on Mac OS X.4 (Tiger)
 --------------------------------------------
 1. Install Apple's Developer Tools.
 
 2. Install the Fink Project's Package manager, fink, obtainable at http://fink.sourceforge.net

-3. Compile and install gnugetopt, readline, ladspa and ladspa-cmt from fink: e.g.
-	fink install gnugetopt
+3. Compile and install libgnugetopt-1.2, readline-4.3, ladspa-1.12 and ladspa-cmt-1.15 from fink: e.g.
+	fink install libgnugetopt

 4. Install MidiShare-1.87 for Mac OS X available from
 	http://www.grame.fr/MidiShare/
@ -16,8 +16,7 @@ Compiling fluidsynth-1.0.5 on Mac OS X.3.5
 6. Edit the "/usr/local/lib/pkgconfig/jack.pc" file using your favorite Unix editor:
 	In the "Libs" line, replace "ljack" with "-framework Jack"
 	
-7. cd to the fluidsynth directory and in the configure script, substitute "-lmidishare" with 
-	"-framework MidiShare".
+7. cd to the fluidsynth directory and in the configure script, substitute "-lmidishare" with "-framework MidiShare".

 8. Run configure with the following options (all on one line in a text editor, then copy and paste into Terminal):
 ./configure --enable-midishare --enable-ladspa --enable-functioncheck --enable-debug --enable-profiling --enable-jack-support "CPPFLAGS=-I/usr/local/include -I/sw/include -I/sw/include/liboss -I/System/Library/Frameworks/MidiShare.framework/Versions/A/Headers -I/System/Library/Frameworks/CoreAudio.framework/Versions/A/Headers -I/Library/Frameworks/Jack.framework/Headers" "LDFLAGS=-L/usr/local/lib -L/sw/lib -framework MidiShare -framework CoreAudio -framework Jack"
@ -43,6 +42,6 @@ Pentium 3+ SSE:        no

 8. make install as root. 

-Ebrahim Mayat <ebmayat@mac.com>
-4th November 2004
+Ebrahim Mayat <emayat@users.sourceforge.net>
+19th May 2005

--- a/fluidsynth/include/fluidsynth/synth.h
+++ b/fluidsynth/include/fluidsynth/synth.h
@ -368,6 +368,12 @@ FLUIDSYNTH_API void fluid_synth_set_gain(fluid_synth_t* synth, float gain);
  /** Get the master gain */
 FLUIDSYNTH_API float fluid_synth_get_gain(fluid_synth_t* synth);

+  /** Set the polyphony limit */
+FLUIDSYNTH_API int fluid_synth_set_polyphony(fluid_synth_t* synth, int polyphony);
+
+  /** Get the polyphony limit */
+FLUIDSYNTH_API int fluid_synth_get_polyphony(fluid_synth_t* synth);
+
  /** Get the internal buffer size. The internal buffer size if not the
      same thing as the buffer size specified in the
      settings. Internally, the synth *always* uses a specific buffer
--- a/fluidsynth/src/fluid_conv.c
+++ b/fluidsynth/src/fluid_conv.c
@ -48,10 +48,14 @@ fluid_conversion_config(void)
   * Note: SF2.01 section 8.1.3: Initial attenuation range is
   * between 0 and 144 dB. Therefore a negative attenuation is
   * not allowed.
+   *
+   * WARNING!!  EMU8k and EMU10k devices don't conform to the SoundFont
+   * specification in regards to the attenuation.  The below calculation
+   * is an approx. equation for generating a table equivelant to the
+   * cb_to_amp_table[] in tables.c of the TiMidity++ source.
   */
-  
  for (i = 0; i < FLUID_CB_AMP_SIZE; i++) {
-    fluid_cb2amp_tab[i] = (fluid_real_t) pow(10.0, (double) i / -200.0);  
+    fluid_cb2amp_tab[i] = (fluid_real_t) pow(10.0, (double) i / FLUID_CB_POWER_FACTOR);
  }

  /* initialize the conversion tables (see fluid_mod.c
--- a/fluidsynth/src/fluid_conv.h
+++ b/fluidsynth/src/fluid_conv.h
@ -28,6 +28,11 @@
 #define FLUID_CB_AMP_SIZE       961
 #define FLUID_PAN_SIZE          1002

+/* EMU 8k/10k don't follow spec in regards to volume attenuation in centibels.
+ * This factor is used in the equation pow (10.0, cb / FLUID_CB_AMP_POWER_FACTOR).
+ * By the standard this should be -200.0.  */
+#define FLUID_CB_POWER_FACTOR	(-531.509)
+
 void fluid_conversion_config(void);

 fluid_real_t fluid_ct2hz(fluid_real_t cents);
--- a/fluidsynth/src/fluid_defsfont.c
+++ b/fluidsynth/src/fluid_defsfont.c
@ -2347,13 +2347,7 @@ load_pgen (int size, SFData * sf, FILE * fd)
 		{		/* inst is last gen */
 		  level = 3;
 		  READW (genval.uword, fd);
-#ifndef MACINTOSH
-		  GPOINTER_TO_INT (((SFZone *) (p2->data))->instsamp) = genval.uword + 1;
-#else
-          /* the codewarrior compiler doesn't seem to accepts the construct
-             above (not an lvalue), so i do it the other way around */
-		  ((SFZone *) (p2->data))->instsamp = (fluid_list_t *) (genval.uword + 1);
-#endif
+		  ((SFZone *) (p2->data))->instsamp = GINT_TO_POINTER (genval.uword + 1);
 		  break;	/* break out of generator loop */
 		}
 	      else
@ -2703,13 +2697,7 @@ load_igen (int size, SFData * sf, FILE * fd)
 		{		/* sample is last gen */
 		  level = 3;
 		  READW (genval.uword, fd);
-#ifndef MACINTOSH
-		  GPOINTER_TO_INT (((SFZone *) (p2->data))->instsamp) = genval.uword + 1;
-#else
-          /* the codewarrior compiler doesn't seem to accepts the construct
-             above (not an lvalue), so i do it the other way around */
-		  ((SFZone *) (p2->data))->instsamp = (fluid_list_t *) (genval.uword + 1);
-#endif
+		  ((SFZone *) (p2->data))->instsamp = GINT_TO_POINTER (genval.uword + 1);
 		  break;	/* break out of generator loop */
 		}
 	      else
@ -3201,5 +3189,3 @@ safe_malloc (size_t size)
    FLUID_LOG (FLUID_ERR, _("Attempted to allocate %d bytes"), (int) size);
  return (ptr);
 }
-
-
--- a/fluidsynth/src/fluid_defsfont.h
+++ b/fluidsynth/src/fluid_defsfont.h
@ -341,6 +341,7 @@ SFData *sfload_file (const char * fname);
 #endif

 #define GPOINTER_TO_INT(p)	((int)   (p))
+#define GINT_TO_POINTER(i)      ((void *)  (i))

 char*	 g_strdup		(const char *str);

--- a/fluidsynth/src/fluid_synth.c
+++ b/fluidsynth/src/fluid_synth.c
@ -371,6 +371,10 @@ new_fluid_synth(fluid_settings_t *settings)
  fluid_settings_register_num(settings, "synth.gain", 
 			      0.2f, 0.0f, 10.0f, 0, 
 			      (fluid_num_update_t) fluid_synth_update_gain, synth);
+  fluid_settings_register_int(settings, "synth.polyphony", 
+			      synth->polyphony, 16, 4096, 0,
+			      (fluid_int_update_t) fluid_synth_update_polyphony,
+                              synth);

  /* do some basic sanity checking on the settings */

@ -776,13 +780,13 @@ fluid_synth_noteoff(fluid_synth_t* synth, int chan, int key)
 /*   fluid_mutex_lock(synth->busy); /\* Don't interfere with the audio thread *\/ */
 /*   fluid_mutex_unlock(synth->busy); */
  
-  for (i = 0; i < synth->nvoice; i++) {
+  for (i = 0; i < synth->polyphony; i++) {
    voice = synth->voice[i];
    if (_ON(voice) && (voice->chan == chan) && (voice->key == key)) {
      if (synth->verbose) {
 	int used_voices = 0;
 	int k;
-	for (k = 0; k < synth->nvoice; k++) {
+	for (k = 0; k < synth->polyphony; k++) {
 	  if (!_AVAILABLE(synth->voice[k])) {
 	    used_voices++;
 	  }
@ -813,7 +817,7 @@ fluid_synth_damp_voices(fluid_synth_t* synth, int chan)
 /*   fluid_mutex_lock(synth->busy); /\* Don't interfere with the audio thread *\/ */
 /*   fluid_mutex_unlock(synth->busy); */

-  for (i = 0; i < synth->nvoice; i++) {
+  for (i = 0; i < synth->polyphony; i++) {
    voice = synth->voice[i];
    if ((voice->chan == chan) && _SUSTAINED(voice)) {
 /*        printf("turned off sustained note: chan=%d, key=%d, vel=%d\n", voice->chan, voice->key, voice->vel); */
@ -888,7 +892,7 @@ fluid_synth_all_notes_off(fluid_synth_t* synth, int chan)
  int i;
  fluid_voice_t* voice;

-  for (i = 0; i < synth->nvoice; i++) {
+  for (i = 0; i < synth->polyphony; i++) {
    voice = synth->voice[i];
    if (_PLAYING(voice) && (voice->chan == chan)) {
      fluid_voice_noteoff(voice);
@ -900,7 +904,7 @@ fluid_synth_all_notes_off(fluid_synth_t* synth, int chan)
 /*
 * fluid_synth_all_sounds_off
 *
- * put all notes on this channel into released state.
+ * immediately stop all notes on this channel.
 */
 int
 fluid_synth_all_sounds_off(fluid_synth_t* synth, int chan)
@ -908,7 +912,7 @@ fluid_synth_all_sounds_off(fluid_synth_t* synth, int chan)
  int i;
  fluid_voice_t* voice;

-  for (i = 0; i < synth->nvoice; i++) {
+  for (i = 0; i < synth->polyphony; i++) {
    voice = synth->voice[i];
    if (_PLAYING(voice) && (voice->chan == chan)) {
      fluid_voice_off(voice);
@ -929,7 +933,7 @@ fluid_synth_system_reset(fluid_synth_t* synth)
  int i;
  fluid_voice_t* voice;

-  for (i = 0; i < synth->nvoice; i++) {
+  for (i = 0; i < synth->polyphony; i++) {
    voice = synth->voice[i];
    if (_PLAYING(voice)) {
      fluid_voice_off(voice);
@ -961,7 +965,7 @@ fluid_synth_modulate_voices(fluid_synth_t* synth, int chan, int is_cc, int ctrl)
 /*   fluid_mutex_lock(synth->busy); /\* Don't interfere with the audio thread *\/ */
 /*   fluid_mutex_unlock(synth->busy); */

-  for (i = 0; i < synth->nvoice; i++) {
+  for (i = 0; i < synth->polyphony; i++) {
    voice = synth->voice[i];
    if (voice->chan == chan) {
      fluid_voice_modulate(voice, is_cc, ctrl);
@ -986,7 +990,7 @@ fluid_synth_modulate_voices_all(fluid_synth_t* synth, int chan)
 /*   fluid_mutex_lock(synth->busy); /\* Don't interfere with the audio thread *\/ */
 /*   fluid_mutex_unlock(synth->busy); */

-  for (i = 0; i < synth->nvoice; i++) {
+  for (i = 0; i < synth->polyphony; i++) {
    voice = synth->voice[i];
    if (voice->chan == chan) {
      fluid_voice_modulate_all(voice);
@ -1374,7 +1378,7 @@ void fluid_synth_set_gain(fluid_synth_t* synth, float gain)
  fluid_clip(gain, 0.0f, 10.0f);
  synth->gain = gain;

-  for (i = 0; i < synth->nvoice; i++) {
+  for (i = 0; i < synth->polyphony; i++) {
    fluid_voice_t* voice = synth->voice[i];    
    if (_PLAYING(voice)) {
      fluid_voice_set_gain(voice, gain);
@ -1390,6 +1394,47 @@ float fluid_synth_get_gain(fluid_synth_t* synth)
  return synth->gain;
 }

+/*
+ * fluid_synth_update_polyphony
+ */
+int fluid_synth_update_polyphony(fluid_synth_t* synth, char* name, int value)
+{
+  fluid_synth_set_polyphony(synth, value);
+  return 0;
+}
+
+/*
+ * fluid_synth_set_polyphony
+ */
+int fluid_synth_set_polyphony(fluid_synth_t* synth, int polyphony)
+{
+  int i;
+
+  if (polyphony < 1 || polyphony > synth->nvoice) {
+    return FLUID_FAILED;
+  }
+
+  /* turn off any voices above the new limit */
+  for (i = polyphony; i < synth->nvoice; i++) {
+    fluid_voice_t* voice = synth->voice[i];    
+    if (_PLAYING(voice)) {
+      fluid_voice_off(voice);
+    }
+  }
+
+  synth->polyphony = polyphony;
+
+  return FLUID_OK;
+}
+
+/*
+ * fluid_synth_get_polyphony
+ */
+int fluid_synth_get_polyphony(fluid_synth_t* synth)
+{
+  return synth->polyphony;
+}
+
 /*
 * fluid_synth_get_internal_buffer_size
 */
@ -1537,20 +1582,24 @@ fluid_synth_nwrite_float(fluid_synth_t* synth, int len,

  /* First, take what's still available in the buffer */
  count = 0;
-  available = FLUID_BUFSIZE - synth->cur;
+  num = synth->cur;
+  if (synth->cur < FLUID_BUFSIZE) {
+    available = FLUID_BUFSIZE - synth->cur;

-  num = (available > len)? len : available;
-  bytes = num * sizeof(float);
+    num = (available > len)? len : available;
+    bytes = num * sizeof(float);

-  for (i = 0; i < synth->audio_channels; i++) {
-    FLUID_MEMCPY(left[i], left_in[i] + synth->cur, bytes);
-    FLUID_MEMCPY(right[i], right_in[i] + synth->cur, bytes);
+    for (i = 0; i < synth->audio_channels; i++) {
+      FLUID_MEMCPY(left[i], left_in[i] + synth->cur, bytes);
+      FLUID_MEMCPY(right[i], right_in[i] + synth->cur, bytes);
+    }
+    for (i = 0; i < synth->effects_channels; i++) {
+      FLUID_MEMCPY(fx_left[i], fx_left_in[i] + synth->cur, bytes);
+      FLUID_MEMCPY(fx_right[i], fx_right_in[i] + synth->cur, bytes);
+    }
+    count += num;
+    num += synth->cur; /* if we're now done, num becomes the new synth->cur below */
  }
-  for (i = 0; i < synth->effects_channels; i++) {
-    FLUID_MEMCPY(fx_left[i], fx_left_in[i] + synth->cur, bytes);
-    FLUID_MEMCPY(fx_right[i], fx_right_in[i] + synth->cur, bytes);
-  }
-  count += num;

  /* Then, run one_block() and copy till we have 'len' samples  */
  while (count < len) {
@ -1756,7 +1805,7 @@ fluid_synth_one_block(fluid_synth_t* synth, int do_not_mix_fx_to_out)
  fluid_profile(FLUID_PROF_ONE_BLOCK_CLEAR, prof_ref);

  /* call all playing synthesis processes */
-  for (i = 0; i < synth->nvoice; i++) {
+  for (i = 0; i < synth->polyphony; i++) {
    voice = synth->voice[i];
    
    if (_PLAYING(voice)) {
@ -1869,7 +1918,7 @@ fluid_synth_free_voice_by_kill(fluid_synth_t* synth)
 /*   fluid_mutex_lock(synth->busy); /\* Don't interfere with the audio thread *\/ */
 /*   fluid_mutex_unlock(synth->busy); */

-  for (i = 0; i < synth->nvoice; i++) {
+  for (i = 0; i < synth->polyphony; i++) {
    
    voice = synth->voice[i];
    
@ -1951,7 +2000,7 @@ fluid_synth_alloc_voice(fluid_synth_t* synth, fluid_sample_t* sample, int chan,
 /*   fluid_mutex_unlock(synth->busy); */

  /* check if there's an available synthesis process */
-  for (i = 0; i < synth->nvoice; i++) {
+  for (i = 0; i < synth->polyphony; i++) {
    if (_AVAILABLE(synth->voice[i])) {
      voice = synth->voice[i];
      break;
@ -1970,7 +2019,7 @@ fluid_synth_alloc_voice(fluid_synth_t* synth, fluid_sample_t* sample, int chan,

  if (synth->verbose) {
    k = 0;
-    for (i = 0; i < synth->nvoice; i++) {
+    for (i = 0; i < synth->polyphony; i++) {
      if (!_AVAILABLE(synth->voice[i])) {
 	k++;
      }
@ -2039,7 +2088,7 @@ void fluid_synth_kill_by_exclusive_class(fluid_synth_t* synth, fluid_voice_t* ne
  
    /* Kill all notes on the same channel with the same exclusive class */
  
-  for (i = 0; i < synth->nvoice; i++) {
+  for (i = 0; i < synth->polyphony; i++) {
    fluid_voice_t* existing_voice = synth->voice[i];
    
    /* Existing voice does not play? Leave it alone. */
@ -2385,7 +2434,7 @@ fluid_synth_get_voicelist(fluid_synth_t* synth, fluid_voice_t* buf[], int bufsiz
 {
  int i;
  int count = 0;
-  for (i = 0; i < synth->nvoice; i++) {
+  for (i = 0; i < synth->polyphony; i++) {
    fluid_voice_t* voice = synth->voice[i];
    if (count >= bufsize) {
      return;
@ -2481,7 +2530,7 @@ void fluid_synth_release_voice_on_same_note(fluid_synth_t* synth, int chan, int
 /*   fluid_mutex_lock(synth->busy); /\* Don't interfere with the audio thread *\/ */
 /*   fluid_mutex_unlock(synth->busy); */

-  for (i = 0; i < synth->nvoice; i++) {
+  for (i = 0; i < synth->polyphony; i++) {
    voice = synth->voice[i];
    if (_PLAYING(voice) 
 	&& (voice->chan == chan) 
@ -2804,7 +2853,7 @@ fluid_synth_set_gen(fluid_synth_t* synth, int chan, int param, float value)

  fluid_channel_set_gen(synth->channel[chan], param, value, 0);

-  for (i = 0; i < synth->nvoice; i++) {
+  for (i = 0; i < synth->polyphony; i++) {
    voice = synth->voice[i];
    if (voice->chan == chan) {
      fluid_voice_set_param(voice, param, value, 0);
@ -2859,7 +2908,7 @@ fluid_synth_set_gen2(fluid_synth_t* synth, int chan, int param,

  fluid_channel_set_gen(synth->channel[chan], param, v, absolute);

-  for (i = 0; i < synth->nvoice; i++) {
+  for (i = 0; i < synth->polyphony; i++) {
    voice = synth->voice[i];
    if (voice->chan == chan) {
      fluid_voice_set_param(voice, param, v, absolute);
@ -2966,7 +3015,7 @@ int fluid_synth_stop(fluid_synth_t* synth, unsigned int id)
  int status = FLUID_FAILED;
  int count = 0;
  
-  for (i = 0; i < synth->nvoice; i++) {
+  for (i = 0; i < synth->polyphony; i++) {

    voice = synth->voice[i];

--- a/fluidsynth/src/fluid_synth.h
+++ b/fluidsynth/src/fluid_synth.h
@ -205,6 +205,7 @@ void fluid_synth_update_presets(fluid_synth_t* synth);


 int fluid_synth_update_gain(fluid_synth_t* synth, char* name, double value);
+int fluid_synth_update_polyphony(fluid_synth_t* synth, char* name, int value);

 fluid_bank_offset_t* fluid_synth_get_bank_offset0(fluid_synth_t* synth, int sfont_id);
 void fluid_synth_remove_bank_offset(fluid_synth_t* synth, int sfont_id);
--- a/fluidsynth/src/fluid_voice.c
+++ b/fluidsynth/src/fluid_voice.c
@ -492,15 +492,17 @@ fluid_voice_write(fluid_voice_t* voice,
    /* The volume amplitude is in hold phase. No sound is produced. */
    goto post_process;
  } else if (voice->volenv_section == FLUID_VOICE_ENVATTACK) {
-    /* the envelope is in the attack section: ramp linearly to max value. */
-    dsp_amp = (fluid_cb2amp(voice->attenuation + voice->modlfo_val * voice->modlfo_to_vol) 
+    /* the envelope is in the attack section: ramp linearly to max value.
+	 * A positive modlfo_to_vol should increase volume (negative attenuation).
+	 */
+	dsp_amp = (fluid_cb2amp(voice->attenuation + voice->modlfo_val * -voice->modlfo_to_vol) 
 	       * voice->volenv_val);
  } else {
    fluid_real_t amplitude_that_reaches_noise_floor;
    fluid_real_t amp_max;
    dsp_amp = fluid_cb2amp(voice->attenuation
 			  + 960.0f * (1.0f - voice->volenv_val)
-			  + voice->modlfo_val * voice->modlfo_to_vol);
+			  + voice->modlfo_val * -voice->modlfo_to_vol);
    
    /* Here we are trying to turn off a voice, if the volume has dropped 
     * low enough.
@ -1629,11 +1631,10 @@ fluid_voice_noteoff(fluid_voice_t* voice)
       * convert from linear amplitude to cb.
       */
      if (voice->volenv_val > 0){
-	fluid_real_t attn_and_lfo = voice->attenuation + voice->modlfo_val * voice->modlfo_to_vol;
-        fluid_real_t amp = voice->volenv_val * pow (10.0, attn_and_lfo / -200.0);
-        fluid_real_t env_value = - ((-200. * log (amp) / log (10.) - attn_and_lfo) / 960.0 - 1);
-        env_value = (env_value < 0.0 ? 0.0 : env_value);
-        env_value = (env_value > 1.0 ? 1.0 : env_value);
+	fluid_real_t attn_and_lfo = voice->attenuation + voice->modlfo_val * -voice->modlfo_to_vol;
+        fluid_real_t amp = voice->volenv_val * pow (10.0, attn_and_lfo / FLUID_CB_POWER_FACTOR);
+        fluid_real_t env_value = - ((FLUID_CB_POWER_FACTOR * log (amp) / log (10.) - attn_and_lfo) / 960.0 - 1);
+	fluid_clip (env_value, 0.0, 1.0);
        voice->volenv_val = env_value;
      }
    }
@ -2080,5 +2081,3 @@ int fluid_voice_optimize_sample(fluid_sample_t* s)
  };
  return FLUID_OK;
 }
-
-