Re: [fluid-dev] Propose change: all_notes_off, all_sounds_off

[David Henningsson]

On 2011-01-26 00:23, jimmy wrote:
> Propose changes for handling of "All notes off", "All sounds off".
>
> GOAL FOR THIS PATCH:
> --------------------
> Turn off all notes/sounds on all channels at once.
>
> If FluidSynth allows the parameter "chan" value -1 to mean operate on all 
> channels, it is a reasonably simple and efficient change.
> --------------------
>
>
> The code changes are in:
>
>     static int fluid_synth_all_notes_off_LOCAL(fluid_synth_t* synth, int chan)
>     static int fluid_synth_all_sounds_off_LOCAL(fluid_synth_t* synth, int chan)
>
> will affect behaviors of:
>
>     int fluid_synth_all_notes_off(fluid_synth_t* synth, int chan)
>     int fluid_synth_all_sounds_off(fluid_synth_t* synth, int chan)
>
> the main difference between the two functions are:
>
>     fluid_synth_all_notes_off() will calls fluid_voice_noteoff();
>     fluid_synth_all_sounds_off_LOCAL() will calls fluid_voice_off(();
>
> although, I don't know what's the differences between fluid_voice_noteoff(), 
> and fluid_voice_off();

fluid_voice_noteoff will make the voice advance to its release phase.
Fluid_voice_off will cut it off immediately.

> ---
>
> Previously, "All notes off", "All sounds off" will only operate on individual 
> channel.
>
> To do so for 16, 32, 48, 64 channels, one has to loop through for each channel. 
>  Not too bad, but looking at the implementation, it is just not effecient at 
> all.
>
> This patch is based on somewhat dated fluidsynth.svn399.20101221 (5 week old) 
> code.
>
> Let's hear if this is a reasonable change to the code base, or not.

Can you elaborate on where this is useful? These are not public API 
functions and aren't used anywhere. I was thinking of removing the ones 
not starting with _LOCAL.

> ----- Patch starts below: -----
> diff -ur fluidsynth.svn399.20101221/src/synth/fluid_synth.c 
> fluidsynth.svn399.20101221.jnAllSoundsOff/src/synth/fluid_synth.c
> --- fluidsynth.svn399.20101221/src/synth/fluid_synth.c  2010-12-21 
> 19:02:53.000000000 -0500
> +++ fluidsynth.svn399.20101221.jnAllSoundsOff/src/synth/fluid_synth.c   
> 2011-01-25 12:57:46.000000000 -0500
> @@ -1455,7 +1455,7 @@
>   /**
>    * Turn off all notes on a MIDI channel (put them into release phase).
>    * @param synth FluidSynth instance
> - * @param chan MIDI channel number (0 to MIDI channel count - 1)
> + * @param chan MIDI channel number (0 to MIDI channel count - 1), (chan=-1 
> selects all channels)
>    * @return FLUID_OK on success, FLUID_FAILED otherwise
>    */
>   int
> @@ -1467,7 +1467,7 @@
>     return fluid_synth_all_notes_off_LOCAL (synth, chan);

-1 won't pass through here - will be stopped on the line above:

fluid_return_val_if_fail (chan >= 0 && chan < synth->midi_channels, 
FLUID_FAILED);

Same thing might apply to the other functions.

// David