I'm forwarding this to QA as I think it could require some discussion
Gale Andrews <email@example.com> changed:
--- Comment #1 from Gale Andrews <firstname.lastname@example.org> 2010-08-19 11:03:49 BST ---
A) Now tested the remaining effects I hadn't, so this seems to be the
definitive list of built-in effects to which the bug applies:
Sliding Time Scale/Pitch Shift
Plus Nyquist process effects are affected, but VST, LADSPA and VAMP plug-ins
are not affected (on basis of those tested).
B) I've added here a related bug that not all effects that change the timeline
move the control points, which is almost as bad as deleting them. So Change
Speed/Tempo and tempo change in Time Scale/Pitch shift should move the control
points. Reverse should move them (Repeat and Truncate Silence already do). To
the extent that Change Pitch modifies length due to its algorithm, possibly
that should move points too?
Obviously if it is not practicable to fix B) after A), B) would have to be
split off to a separate bug.
The ability to copy and paste Envelopes would be extremely useful in
many other situations.
I'm not sure if it currently exists as a "Feature Request", but I
expect that may users would love to be able to copy an envelope from
one track and paste it onto another track.
Ideally, such behaviour should not be restricted to tracks of the same
type - for example it should be possible to copy an envelope from a
stereo track and paste it over a mono track. Envelopes are currently
all "mono" in that they are just one set of control points, not one set
While on the subject of Copy/Paste Control Points - it would be a great
feature to be able to save/export the control points for use in other
projects. Creating a good fade envelope can be very time consuming, and
has to be repeated every time. How much better would it be to be able
to just export the envelope as a txt/xml file, and then reuse it over
and over in other projects?
If the behaviour of Control Points in the case of "Reverse" is going to
be changed, then I think that these proposals should be considered now
so as to avoid breaking compatibility with current Audacity Projects.
On a second, but strongly related point (possibly even the same
So far we have only discussed Effects.
What about "Generate"?
If you generate a tone into a track that contains Envelope Control
Points, should it replace the track, or just replace the audio in the
I think the logical answer would be to just change the audio content.