[fluid-dev] Code patch for GM, GS, XG "system-reset" SysEx's, and MasterVolume SysEx

[jimmy]

Attached is a patch for 4 SysEx messages.  This allow Fluidsynth to 
automatically switch between GM, GS, XG mode on the fly, without having to 
restart, that is.  Often a "reset" sysex is sent at beginning of a midi file, 
but not always.

Sys-Ex "reset" messages:

   myweb.tiscali.co.uk/mikesmusic/my_technical_articles2.html#sysex
   
   1. GM Reset (understood by every GM-compatible instrument)
   Sys-Ex String: F0 7E 7F 09 01 F7

   2. Roland GS Reset (Understood by all Roland GS instruments)
   Sys-Ex String: F0 41 10 42 12 40 00 7F 00 41 F7

   3. Yamaha XG reset (Understood by all Yamaha XG instruments)
   Sys-Ex String: F0 43 10 4C 00 00 7E 00 F7

About master volume:

   home.roadrunner.com/~jgglatt/tech/midispec/mastrvol.htm

   Master Volume SysEx:   0xF0 0x7F 0x7F 0x04 0x01 0xLL 0xMM 0xF7

where (0xLL=LSB, 0xMM=MSB), where 7F 7F is maximum volume.

My patch ignores LSB (LSB=0), simply takes the MSB (7-bit, max value 127) 
devide by 12.70 to get the range of [0.0 - 10.0].

-----

In adding SysEx handler for master volume adjustment ("gain" in Fluidsynth), I 
found a few inconsitencies regarding "gain":

       -g, --gain
              Set the master gain [0 < gain < 10, default = 0.2]

which sets fluidsynth settings of:

       synth.gain FLOAT [min=0.000, max=10.000, def=0.200] REALTIME
              Master synthesizer gain.

While the fluidsynth command shell and manual page have:

       gain value
              Set the master gain (0 < gain < 5)

but the shell-command handler fluid_handle_gain() doesn't try to scale it in 
anyway to 10.0.  Any reason for that?  Or, it's just an oversight (in previous 
changes).

In this patch, I go ahead and change all references regarding maximum "gain" 
from 5 to 10.  Let me know if those need to be left alone.

Jimmy

fluidsynth_sysex_010.patch
Description: Text Data