/*!

\page SendingMIDI Sending MIDI events

Once the synthesizer is up and running and a SoundFont is loaded, most people
will want to do something useful with it. Make noise, for example. MIDI
messages can be sent using the fluid_synth_noteon(), fluid_synth_noteoff(),
fluid_synth_cc(), fluid_synth_pitch_bend(), fluid_synth_pitch_wheel_sens(),
and fluid_synth_program_change() functions. For convenience, there's also a
fluid_synth_bank_select() function (the bank select message is normally sent
using a control change message). 

The following example show a generic graphical button that plays a note when
clicked: 

\code
class SoundButton : public SomeButton
{
public:	

    SoundButton() : SomeButton() {
        if (!_synth) {
            initSynth();
        }
    }

    static void initSynth() {
        _settings = new_fluid_settings();
        _synth = new_fluid_synth(_settings);
        _adriver = new_fluid_audio_driver(_settings, _synth);
    }

    /* ... */

    virtual int handleMouseDown(int x, int y) {
        /* Play a note on key 60 with velocity 100 on MIDI channel 0 */
        fluid_synth_noteon(_synth, 0, 60, 100);
    }

    virtual int handleMouseUp(int x, int y) {
        /* Release the note on key 60 */
        fluid_synth_noteoff(_synth, 0, 60);
    }

protected:

    static fluid_settings_t* _settings;
    static fluid_synth_t* _synth;
    static fluid_audio_driver_t* _adriver;
};
\endcode

*/