23 Mar
2011
23 Mar
'11
1:39 p.m.
in ardour3, which the only implementation i want to talk about, we
have a basic object called a Controllable which consists fundamentally
of just a set() and get() method pair and a callback/signal that is
called/emitted when the value changes. Controllables are used for just
about everything in ardour that can "be controlled", and they all have
unique, persistent ID.
MIDI bindings link a particular MIDI message (e.g. a CC number) with
the ID of a Controllable, and will generally cause the set() method of
the object to be called when the message is received.
On 3/22/11, Harry Van Haaren <harryhaaren(a)gmail.com> wrote:
Hey guys,
I'm wondering how to approach creating a MIDI map to all controllers
available in the GUI. Needless to say I can hard code in a MIDI CC, and from
JACK's process callback call the function that I want to map that control
to, but that's a little rigid.
I like Ardour's one-click map idea, and I'm wondering how its implemented.
Here's what I concluded so far:
On mouse_3 down, pop up dialog, send message to JACK process to keep next
MIDI input stored somewhere. That's the CC to map
Where I'm getting stuck is how to make each CC point to a different
"parameter" in the software, or a different function in the code. Function
pointers come to mind, but somehow I don't like that idea much. Creating a
generic interface to map every control in the entire engine might work, but
I think that may be a little overkill?
I'd be interested to hear how various projects handles this internally, if
anybody wants to chip in?
Cheers, -Harry