Re: [Rosegarden-devel] MIDI recording

[Chris C. <ca...@al...>]

Richard Bown wrote:
>   rosegardenguidoc.cpp::convertToSinglePoint()
> 
> C & G you might want to have a look at this to make sure it's doing
> everything right.

Well, it doesn't look terribly efficient, but I'm not sure
I want to get into that at the moment -- it's probably okay
in real-world circumstances.

As for the detail, I'd say there were a couple of things
you'd be well advised to do differently:

 -- I suggest you don't use the MatrixHelper methods to
    add and remove events, but simply use Segment::insert
    and Segment::eraseSingle.  And then _after_ all the
    work on notes is done, call Segment::normalizeRests
    on the whole segment to fix up the rests.  This also
    means you could (and should) lose all the calls to
    Segment::fillWithRests in the method that actually
    builds up the recording segment.  (Take a look at
    MidiFile.cpp, we're doing a similar thing there these
    days.)

 -- It's generally dangerous to erase things from a
    segment while iterating over it, because erasing will
    invalidate the iterator.  I presume it works for you,
    but I'm slightly surprised that it should because I'd
    have thought deleting *it would cause trouble; maybe
    the immediate insert happens in the same place by
    coincidence, or something.  You should be able to
    delete *oIt ithout problems though.  My generally
    paranoid approach has been to build up a vector of
    iterators to erase and a vector of events to insert
    and then erase and insert them all in a single-minded
    loop at the end.  (grep for "toErase" or "toInsert".)
    Guillaume may have more reasonable suggestions.


> Lots of annoying work at the moment trying to fix stuff that's kind of
> gone off all for not much measurable gain.

Yeah, we seem to have gone a bit sour on quality lately.
We'd probably benefit from forgetting about new features
for a week or so and concentrating on getting the ones we
have working correctly -- I'm certainly going to try to
work up the discipline to do that myself.


Chris