Older blog entries for ensonic (starting at number 121)


After lots of changes I have switched the code permanently to the new sequence model. It saves about 170 lines of code in the sequence-page source. There is some potential to save more though.

I also did more work on state persistence. A song now contains more information (selected machines, pattern, options) and these things are restored when loading a song.

Another good change was moving the song-unsaved flag from the song (core-library) to the edit application. This make the core library more light-weight. The editor application can now determine whether there is something to save by combining the unsaved-flag and the undo/redo stack. The unsaved-flag is still needed as I feel not everything needs to go to the undo/redo stack (like selecting a machine). Undo/redo looks quite complete now. I found a solution for my last issue, although I am still not entirely happy with it.

I also made a few startup time improvements. Found a weird issue with the interaction-controller library probing joystick devices. One ioctl on joy devices for hdaps devices is hanging for quite a bit.

Finally I did a huge cleanup on or somewhat uncommon header file setup. We always had a header declaring the types and one the methods. This helped with include conflicts. But now we have 50% less files to care and I just needed 2 forward declarations.

Again several bugs were fixed. I will check remaining reported bugs and hope that everything is fine to consider releasing 0.6.

253 files changed, 27205 insertions(+), 26602 deletions(-)

Another month with good progress. I've started with the undo/redo parts in the sequencer view. Most of the edits are handled now. I am still stuck with one problem though. So far the order of signal handler on object removal did not matter. Now it does :/ There are things that when they get removed remove other things. And that causes chains of modificatins that in the change log would overwrite (shadow) the save data. Not yet sure how to solve that. I'll probably confront someone at the desktop summit with the problem over some beer in the hope that I find a solution while I am explaining the issue :) As a good side effect of the undo/redo work, I could remove the warning dialogs that I was showing when removing things. Makes the editor more pleasant to use.

During my july trip to mountain view I brought two cheap midi controlers - korg nanokontrol and nanokeys 2. The nanokeys 2 is not so nice, but the nanokontrol seems to be okay. Unfortunately I didn't notice is is the old model, the nanokontrol 2 has more keys. I have played quite a bit with the nanokontrol in buzztard. Found and fixed a few bugs. One thing I definitely needed to do is to store the keys one has trained. Thanks to my long train journeys between munich and leipzig these days, that got implemented. For the nanokeys I need to still do a couple of things and those will have to wait for the next version.

As I was blocked on the undo/redo I did more small mini-songs. As usual found a couple of bugs. Buzztard stores timestamps in the song (like when it was created and when it was saved the last time). When closing a song with changes it warns you about loosing the changes for the last n hours/minutes. Thas was completely off if one loads a song and makes some changes. I need to set the last-saved to the time of the first change. A few other bugs were related to 64bit arch and using wrong int types in varargs functions. I also made some ui improvements. The settings hide more unusable audiosinks (apexsink, sfsink), especially probing apexsink caused long delays as I don't have the hardware for it.

One issue that I had no good explanation for but that was quite apparent when doing demos was small breaks when the song loops. Especially at the first loop it caused a bad glitch and later it sometimes played a bit too much or skipped something when wrapping around. I had made some test apps for it, but could not reproduce it there so far. Finally I looked at it again and found a small self-contained testcase that was reproducing it. On that case I could narrow it down to a combination of two gstreamer elements causing it. Still it was not straight forward to fix it, after all it is not crashing or such. I decided that the only way forward was to get a good picture of what is happening and verifying the events step by step. Voila, we now have a improved gst-tracelib and a gnuplot script for plotting event over time. Would be nice to have a more interactive UI for gnuplot though. I filed a bug and put the data there, if you are curious about the graphs. After some more nights I found the issue and the fix for the adder plugin is now upstream. A simillar change needs to be done for the videomixer elements (will look into that soon).

43 files changed, 2779 insertions(+), 496 deletions(-)

This month I made great progress. I have been making several small demo songs and found+fixed quite many bugs and glitches along with that.

After a little break I took up undo/redo work and could make good progress. Now also pattern property changes (name and length) are tracked. In the sequence the boilerplate code is there, single edits, track and property changes are handled. In the machine view the initial machine position is tracked in the change-log.

In the middle of the month I did doc updates - api docs had some stuff missing and the user help finality has more beef and short-cut tables for all the keyboard accelerators.

OmniMancer on irc gave me some good first perspective usage experience. I added a blacklist filter to hide gstreamer elements from the menu that are known to be not useful for buzztard (e.g. dtmfsrc). Also some machines used GTypes not yet supported by the UI - this is now fixed. With that came some fixes in
pattern editing (blending parameters wasn't working in all cases). I also added a flip operation to the patterns. Also to make a few things easier for new users I added two items to help menu - file a bug and goto irc. The later fires up the freenode webirc as xdg-open seems to be unable to launch e.g. xchat for irc://

I have started to write the missing treemodel for the sequence view and used that changed to overhaul a few things. Even without the new model its quite a bit faster as we do less model rebuilds (e.g. when expanding the length). Also the row-shading code is simpler and with that the cell-data functions. Finally
the pattern usage tracking is now using a hashtable instead of rescanning the sequence.

With all those changes comes a bag of bug fixes - I'll skip listing them here - it is all in the change log. Also I did a bit of code cleanups and reorgs. Like using macros for the GType handling to save lines of code. Or bump the gtk+ version (2.10.12) to get rid of fallback code. Finally I rechecked a glib bug regarding mime-matching. It's fixed since a while, but I still saw it, as the .recently-used.xbel file had the wrong mime type from the time when glib had the bug in there. Maybe it would be good to trim that file from time to time. Imho
it should also be in $XDG_CACHE_DIR and not $HOME, but that is a different story.

48 files changed, 2712 insertions(+), 1250 deletions(-)
This is not Helsinki

Yes, that means 'bye bye Nokia'. The recent events have killed the last remains of trust in the companies leadership. It is quite sad to see how things get ramped down.

The new chapter is called Google Germany. I just started in the office in Munich three days ago. So far everything sounds cool. I'll write about it when there is something to tell :)
buzztard & gstreamer

In the begining of the month I finished the new treeview models. There were a couple of corner cases I did not handled yet. I did some thinking about the remaining model, but did not yet write any code for it. Instead I did some code review of the whole project leading to numerous small cleanups and fixes. I also got rid of some holes in the api docs.

Otherwise I worked more on GStreamer and gtk-doc. In GStreamer I mostly hacked on a baseclass for audio-visualizers which is now in gst-plugins-bad (together with 4 elements using it).

There are some other reasons for not having so much time to hack on, of which I will shortly speak about :)

32 files changed, 1848 insertions(+), 444 deletions(-)

After last month spectrum analyzer work, I also looked at the volume meters again. Handling the updates is a bit tricky as I need to sync them to the audio playback. Now I have optimizations in place to skip updates when the meter is zero or maxed and has not changed. This is actually quite often the case.

I also fixed a small UI glitch; song-io plugins did not tell so far whether they support saving and/or loading. Thus one could end up selecting a format and then getting an error. Now one will see only the formats that plugins can handle.

Finally I got around catching up on the docs too. Now all dialogs have some docs including screenshots.

One refactoring I was actually considering to push for after the next release was getting rid of the GtkListStores and use real GtkTreeModels instead. The disadvantage of a ListStore is that it is static, if the underlying object is dynamic one needs to manually synchronize it. This enlarges the code and also the duplicated data storage uses memory. Writing own models was in the end not so difficult, it is quite some boilerplate code though. The first one I wrote is a object-list-model. It allows to bind object-properties to model columns. If e.g. a field changes, the model notifies and the view updates. The whole thing could become more generic if we would have an iterator interfaces and the collection types (list, array, ..) would be gobjects implementing the iface. Well, I am not the first to notice that :). Next I made 2 specialized models and started to take them into use. As a bonus e.g. the machine model provides a nice logical sorting. One more model to implement and switch to.

72 files changed, 6268 insertions(+), 1250 deletions(-)

best birthday gift ever

I got totally awesome birthday gifts today - Gnome 3 and Banshee 2 - thanks everybody :). When I asked on the irc what people will then release on my next anniversary - "well, like gnome 3.6 ;)" was the answer.

My personal birthday gift was this one. It is going to be fun.


I have been refactoring GStreamer's spectrum analyzer. It is now working faster and also allows to get per-channel results. For testing I updated buzztard to check if one has the new version and if so show per channel graphs. While hacking on the analyzer graphs I have also refactored the code, so that now it is possible to probe the final output as well.

I spend the bigger part of the month on the tests again. I had an unref too much somewhere. Even after all the work in refdbg this is still difficult to track down. Eventually I found it and now all tests are green.

43 files changed, 796 insertions(+), 100 deletions(-)

buzztard I was testing buzztard a lot on my MeeGo netbook this month. As screen space is more precious on netbooks I was running it often in fullscreen mode and noticed that some windows seem to not open. When leaving full screen the windows appeared. Somehow they opened behind the main window. I looked over all child windows and dialogs and cleaned up the handling with a helper method doing:
  gtk_window_set_transient_for(window, main_window);
  gtk_window_set_destroy_with_parent(window, TRUE);
On my desktop it works fine on the netbook the problem still happens :/ No idea right now. As a good side effect I ensured that all dialogs have a properly set default response.

I was also running the performance tests and did some oprofiling. I knew already that my data-fixup code for buzzmachines caused quite some overhead. It is handling denormals and marking full zero buffers as empty. I now added code that sets the FPU on x86 machines to DAZ|FZ mode from the application and disable the fixup code. On my netbook my 11 min benchmark song renders in about 1 min instead of 1:20 min before. On my desktop most of the change are hard to measure as it already only takes 5 seconds :). Anyway the oprofile runs confirm the speedup. The code disappeared from the top 20.

The pattern editor widget becomes slow when getting large. Some text drawing operations look expensive. For a start I ported the whole widget to use cairo, but that does not take care of the slowness. After more measurements it becomes clear that I need to rework this more. I need to render it offscreen and reply to expose events by copying pixels.

I also worked a bit more on the interaction-controller library. udev/hal code is refactored into extra objects (saves me a lot of #ifdefs). It also has some tests now. I still have a mysterious issue with udev. Run this stand alone example as told in the header - for me valgrind complains about uninitialized data access. It only seems to happen when you have a /dev/input/mice which all my computers have. I have a workaround, but believe more testing from other would be great.

44 files changed, 1087 insertions(+), 317 deletions(-)

As there was no project news over x-mas, I have a slightly longer one this time. Before I dive into the usual code changes, something else - tadaa - we have a new webpage. The previous page was a mediawiki with a few customizations. Now we use a combo of wordpress-3 and mediawiki. Both use a similar theme (based on the arch linux one). Wordpres gives as news, forum, social-network features and much more. The first days I was suffering a lot from wordpress account creation spam. Luckily this seems to be under control now. The concept and a lot of the work was done by Joe Pea. We both have quite a few more things on the todo list. One of the next items is single sign in for wordpress and mediawiki. Stay tuned.

In the last two month I improved the song-recovery workflow. The recovery is now giving better feedback to the user and we're properly cleaning up afterwards. The machine machine and pattern view do now have almost full undo/redo.

Quite several times already I had to deal with a dialog containing a treeview showing a list of items. The latest example is the song-recovery dialog. Giving such a dialog a nice good initial size is tricky. The treeview usually goes into a scrolled window. By default one can see the headers and maybe one line. Of course one can resize the dialog a bit, but as the line height is not easy to figure it is still not easy. One approach I came up with is to grow the dialog to show all lines until it would exceed a certain limit. The limit would be e.g. half of screen or window height. The code for that is quite simple:

  static void
  on_list_size_request(GtkWidget *widget,GtkRequisition *requisition,gpointer user_data)
    gint max_height=gdk_screen_get_height(gdk_screen_get_default())/2;
    gint height=2+MIN(requisition->height,max_height);

/* make sure the dialog resize without showing a scrollbar until it would * reach half screen height */ gtk_widget_set_size_request(gtk_widget_get_parent(widget),-1,height); }

Another thing in gtk that I wonder if it has a better solution is the disposal of popup-menus. The problem is that gtk_menu_popup is not taking ownership of the menu, but there seems to be now event when the menu is done, so that one can unref it. The only solution I can see is the pre- create the menu and ref-sink it. When the entity that owns it is disposed it can destroy and unref it.

As we're quite gtk related in this time anyway one more discovery. Listening for key-press-event instead of key- release-event and widgets makes key-repeat work. Have added that to the gtk api docs.

Beside all the things above a couple of bug-fixes went in (make preferences in machines work (e.g. choosing fluidsynth instruments). I did some refactoring on midi controller handling; one can use the pitchwheel now and continuous controllers work better. Finally the dialogs warning about unsaved changes are more user-friendly; they now show the time passed since last saved/created in addition to the timestamp.

50 files changed, 2402 insertions(+), 1183 deletions(-)

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