openshot.developers team mailing list archive

[francesco fantoni <francesco@xxxxxxxxxxxxxxxxxxxx>]

Going on with experimenting with history/undo system.
I've implemented a history stack, but I'm having a bit of trouble with
visibility/audio buttons in clip widgets: they generate two different
events, one correctly for button toggling, and another for clip
dragging, that is unwanted and makes difficult to track the correct
changes for undo/history system.
any hint?

lp:~francesco-hermanitosverdes/openshot/francesco_undo_redo_test

francesco





Il giorno gio, 21/01/2010 alle 12.53 +0100, francesco fantoni ha
scritto:
> I've made a proof-of-concept implementation in a branch:
> 
> lp:~francesco-hermanitosverdes/openshot/francesco_undo_redo_test
> 
> apparently it can be done, and it seems fast enough, but it must be
> further investigated.
> 
> hope someone with better knowledge than me can review the code and see
> if it is worth going on in this direction.
> 
> ciao, francesco
> 
> 
> 
> 
> Il giorno gio, 21/01/2010 alle 10.33 +0000, Andy Finch ha scritto:
> > The link below uses a stack/list, but keeps it in memory (using a
> > python list object) rather than writing to disk, so it is essentially
> > the same thing in principle. 
> > 
> > What I do like the idea of is to write to disk a separate 'backup' of
> > the project file, perhaps using an autosave, so in the event of a
> > crash or some other event that corrupts the project file, there is the
> > option to restore back to one of the previous backup copies. But
> > that's a different discussion I guess.
> >  
> > But I must admit I'm no expert in things like this, I was just having
> > a browse around to see how other pygtk apps handle undo :-)
> > 
> > Cheers,
> > Andy.
> > 
> > 2010/1/21 francesco fantoni <francesco@xxxxxxxxxxxxxxxxxxxx>
> >         I was considering an approach similar to what is used in
> >         saving project
> >         file:
> >         using cPickle to create a "state" of project object (written
> >         to a
> >         StringIO object), and inserted in a "history" stack/list.
> >         This way we could have a undo/redo system, but a history
> >         system as well,
> >         with the possibility to go back to any previous state of the
> >         working
> >         session, and besides it would use a rather simple trick, with
> >         parts of
> >         code already implemented.
> >         History stack size can be limited to a certain number of
> >         stages with
> >         user preferences system, or set to a reasonable hardcoded
> >         value.
> >         With some work on set_project_modified() function that can
> >         trigger
> >         project's state storing action...
> >         The doubts I have are about memory usage (not a great issue I
> >         suppose
> >         using binary protocol of cpickle and with a stack limited to
> >         e.g. 10
> >         passes) and speed (but cPickle and cStringIO are supposed to
> >         be rather
> >         fast)
> >         what do you think?
> >         
> >         francesco
> >         
> >         
> >         Il giorno gio, 21/01/2010 alle 09.56 +0000, Andy Finch ha
> >         scritto:
> >         
> >         > I haven't, I've been looking at other stuff. Although I have
> >         been
> >         > looking around recently at how undo is done in python and
> >         came across
> >         > this, which may help:
> >         >
> >         > http://www.nongnu.org/skencil/doc.html
> >         >
> >         > then follow the link to the undo documentation:
> >         >
> >         > http://www.nongnu.org/skencil/Doc/devguide-19.html#N1
> >         >
> >         > Cheers,
> >         > Andy.
> >         >
> >         > 2010/1/21 francesco fantoni <francesco@xxxxxxxxxxxxxxxxxxxx>
> >         >         just to know, has someone already started working on
> >         the
> >         >         undo/history
> >         >         thing?
> >         >
> >         >         best to all,
> >         >         francesco
> >         >         --
> >         >         architetto Francesco Fantoni
> >         >         <HVA - Hermanitos Verdes Architetti>
> >         >         l.go san giacomo, 38
> >         >         I-41100 modena (italia)
> >         >         tel.& fax. +39.059.217554
> >         >         skype:  hva_studio
> >         >         e.mail: francesco@xxxxxxxx
> >         >         web:    http://www.hv-a.com
> >         >
> >         >
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> >         
> >         --
> >         
> >         architetto Francesco Fantoni
> >         <HVA - Hermanitos Verdes Architetti>
> >         l.go san giacomo, 38
> >         I-41100 modena (italia)
> >         tel.& fax. +39.059.217554
> >         skype:  hva_studio
> >         e.mail: francesco@xxxxxxxx
> >         web:    http://www.hv-a.com
> >         
> >         
> > 
-- 
architetto Francesco Fantoni
<HVA - Hermanitos Verdes Architetti>
l.go san giacomo, 38
I-41100 modena (italia)
tel.& fax. +39.059.217554
skype:  hva_studio
e.mail: francesco@xxxxxxxx
web:    http://www.hv-a.com