[LAD] MIDI in jack

Len Ovens len at ovenwerks.net
Sun Jul 6 23:45:44 UTC 2014

On Sun, 6 Jul 2014, Pedro Lopez-Cabanillas wrote:

> On Sunday 06 July 2014 09:44:57 Len Ovens wrote:
>> use the Xorg keyboard inputs. This means that if I have a synth connected
>> to virtual kb, as soon as I try to change the synth patch, I loose my
>> virtual keyboard access because keyboard follows focus to the synth
>> application (which is what we want almost always). That is why I have to
>> run as a system user.
> VMPK has an option (Edit->Preferences):
> [x] Grab Computer Keyboard
> If you enable this option, VMPK grabs keyboard events no matter which
> application has the focus. It will be temporarily disabled when you minimize
> VMPK's main window, and re-enabled when restoring it again. It is also
> disabled when you open a dialog.

So not very global.
> To do so in X11 applications you only need to invoke the XGrabKeyboard
> function: http://www.x.org/archive/X11R7.5/doc/man/man3/XGrabKeyboard.3.html
> There may be problems using this function in your program while running other
> gtk+ based programs at the same time, because it is used by gtk+ menus as
> well.

So that makes it pretty much not usable for my use. I will have to catch 
it before X does.... or set X up to look at only one keyboard. I want it 
to be as solid as any HW midi controler, not half there.

By doing it early on, it is possible to only catch some of the keyboard 
and not the whole thing. The numberic key pad on most keyboards is 
redundant as all of the keys can be be gotten somewhere else. In that case 
the numlock key can be used to switch midi mode in and out. Many Numeric 
pads still have the non-numeric symbols on them that might work well for 
transport control. Quite easy to only affect a second keyboard.

In fact for my own use I will be using a second keyboard (or it's board at 
least). This is not quite so nice as something that looks like a standard 
USB midi device, but that is what I am trying first. I am also looking at 
various midi controler brains (or plans) that are available as I may go 
that route for faders.

Len Ovens

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