[Suggestion] Disable chorus and reverb for Fluidsynth by default

[sinisterseed]

Chorus and reverb usually make the music sound awful when played back through Fluidsynth in PrBoom, and the worst part is that there are no menu entries to turn them off, they have to be manually turned off in the config once found.

The majority of MIDIs are not designed with these in mind, so there's no real good reason to keep them ON by default.

[fabiangreffrath]

This disables chorus and reverb by default and mitigates their impact for those with an existing config based on the suggestions by @kitchen-ace found in chocolate-doom/chocolate-doom#1261

diff --git a/prboom2/src/MUSIC/flplayer.c b/prboom2/src/MUSIC/flplayer.c
index 2d5eff1e..09c5fd49 100644
--- a/prboom2/src/MUSIC/flplayer.c
+++ b/prboom2/src/MUSIC/flplayer.c
@@ -144,6 +144,20 @@ static int fl_init (int samplerate)
   FSET (int, "synth.chorus.active", mus_fluidsynth_chorus);
   FSET (int, "synth.reverb.active", mus_fluidsynth_reverb);

+  if (mus_fluidsynth_chorus)
+  {
+    FSET (num, "synth.chorus.depth", (double) 5);
+    FSET (num, "synth.chorus.level", (double) 0.35);
+  }
+
+  if (mus_fluidsynth_reverb)
+  {
+    FSET (num, "synth.reverb.damp", (double) 0.4);
+    FSET (num, "synth.reverb.level", (double) 0.15);
+    FSET (num, "synth.reverb.width", (double) 4);
+    FSET (num, "synth.reverb.room-size", (double) 0.6);
+  }
+
   // gain control
   FSET (num, "synth.gain", mus_fluidsynth_gain / 100.0); // 0.0 - 0.2 - 10.0
   // behavior wrt bank select messages
diff --git a/prboom2/src/m_misc.c b/prboom2/src/m_misc.c
index ec04c31b..8f4daa43 100644
--- a/prboom2/src/m_misc.c
+++ b/prboom2/src/m_misc.c
@@ -381,8 +381,8 @@ default_t defaults[] =
   {"mus_extend_volume",{&mus_extend_volume},{0},0,1,
    def_bool,ss_none}, // e6y: apply midi volume to all midi devices
 #endif
-  {"mus_fluidsynth_chorus",{&mus_fluidsynth_chorus},{1},0,1,def_bool,ss_none},
-  {"mus_fluidsynth_reverb",{&mus_fluidsynth_reverb},{1},0,1,def_bool,ss_none},
+  {"mus_fluidsynth_chorus",{&mus_fluidsynth_chorus},{0},0,1,def_bool,ss_none},
+  {"mus_fluidsynth_reverb",{&mus_fluidsynth_reverb},{0},0,1,def_bool,ss_none},
   {"mus_fluidsynth_gain",{&mus_fluidsynth_gain},{50},0,1000,def_int,ss_none}, // NSM  fine tune fluidsynth output level
   {"mus_opl_gain",{&mus_opl_gain},{50},0,1000,def_int,ss_none}, // NSM  fine tune opl output level