1 files changed, 49 insertions, 14 deletions

diff --git a/sys/i386/isa/sound/gus_vol.c b/sys/i386/isa/sound/gus_vol.c
index 6e56d546cea5..055a1170e9fb 100644
--- a/sys/i386/isa/sound/gus_vol.c
+++ b/sys/i386/isa/sound/gus_vol.c
@@ -1,17 +1,18 @@
-/* 
+/*
  * gus_vol.c - Compute volume for GUS.
- * 
+ *
  * Greg Lee 1993.
  */
 #include "sound_config.h"
 #ifndef EXCLUDE_GUS
+#include "gus_linearvol.h"
 
 #define GUS_VOLUME	gus_wave_volume
 
 
 extern int      gus_wave_volume;
 
-/* 
+/*
  * Calculate gus volume from note velocity, main volume, expression, and
  * intrinsic patch volume given in patch library.  Expression is multiplied
  * in, so it emphasizes differences in note velocity, while main volume is
@@ -20,7 +21,7 @@ extern int      gus_wave_volume;
  * to expression controller messages, if they were found to be used for
  * dynamic volume adjustments, so here, main volume can be assumed to be
  * constant throughout a song.)
- * 
+ *
  * Intrinsic patch volume is added in, but if over 64 is also multiplied in, so
  * we can give a big boost to very weak voices like nylon guitar and the
  * basses.  The normal value is 64.  Strings are assigned lower values.
@@ -31,27 +32,27 @@ gus_adagio_vol (int vel, int mainv, int xpn, int voicev)
   int             i, m, n, x;
 
 
-  /* 
+  /*
    * A voice volume of 64 is considered neutral, so adjust the main volume if
    * something other than this neutral value was assigned in the patch
    * library.
    */
   x = 256 + 6 * (voicev - 64);
 
-  /* 
-   * Boost expression by voice volume above neutral. 
+  /*
+   * Boost expression by voice volume above neutral.
    */
   if (voicev > 65)
     xpn += voicev - 64;
   xpn += (voicev - 64) / 2;
 
-  /* 
-   * Combine multiplicative and level components. 
+  /*
+   * Combine multiplicative and level components.
    */
   x = vel * xpn * 6 + (voicev / 4) * x;
 
 #ifdef GUS_VOLUME
-  /* 
+  /*
    * Further adjustment by installation-specific master volume control
    * (default 60).
    */
@@ -72,7 +73,7 @@ gus_adagio_vol (int vel, int mainv, int xpn, int voicev)
   else if (x >= 65535)
     return ((15 << 8) | 255);
 
-  /* 
+  /*
    * Convert to gus's logarithmic form with 4 bit exponent i and 8 bit
    * mantissa m.
    */
@@ -89,14 +90,14 @@ gus_adagio_vol (int vel, int mainv, int xpn, int voicev)
 	n >>= 1;
 	i++;
       }
-  /* 
+  /*
    * Mantissa is part of linear volume not expressed in exponent.  (This is
    * not quite like real logs -- I wonder if it's right.)
    */
   m = x - (1 << i);
 
-  /* 
-   * Adjust mantissa to 8 bits. 
+  /*
+   * Adjust mantissa to 8 bits.
    */
   if (m > 0)
     {
@@ -109,4 +110,38 @@ gus_adagio_vol (int vel, int mainv, int xpn, int voicev)
   return ((i << 8) + m);
 }
 
+/*
+ * Volume-values are interpreted as linear values. Volume is based on the
+ * value supplied with SEQ_START_NOTE(), channel main volume (if compiled in)
+ * and the volume set by the mixer-device (default 60%).
+ */
+
+unsigned short
+gus_linear_vol (int vol, int mainvol)
+{
+  int             mixer_mainvol;
+
+  if (vol <= 0)
+    vol = 0;
+  else if (vol >= 127)
+    vol = 127;
+
+#ifdef GUS_VOLUME
+  mixer_mainvol = GUS_VOLUME;
+#else
+  mixer_mainvol = 100;
+#endif
+
+#ifdef GUS_USE_CHN_MAIN_VOLUME
+  if (mainvol <= 0)
+    mainvol = 0;
+  else if (mainvol >= 127)
+    mainvol = 127;
+#else
+  mainvol = 128;
+#endif
+
+  return gus_linearvol[(((vol * mainvol) / 128) * mixer_mainvol) / 100];
+}
+
 #endif