[Bug] Does not load new data when using the -l and -d flag (would be good for automatic imagefile creation)

[mistermult]

Problem description

If the program is started with the flag '-l layoutfile.xml -d rosbag.bag' the new data is not displayed. Instead the old data from the previous run is displayed. Bug is in the Version for ROS kinetic and ROS melodic.

Steps to reproduce (important)

• Operative System: Ubuntu 18.04 inside Docker or outside
• Steps:
  • Open Plotjuggler
  • Open a bag file 'bag1.bag'
  • Create some plots
  • Save the layout to layout.xml
  • Close the program
  • Open the program from commandline with rosrun plotjuggler PlotJuggler -d bag2.bag -l layout.xml
  • Press Ctrl+A to import everything. Press OK. You see a progress bar for the import.
  • Confirm that you want to replace the old data.
  • Another progress bar for loading data appears.
  • Plots with data from'bag1.bag is shown.

Background

I have done the testing manually (my own hands and monitor). In the end, i want to automatically create plots from files from a given layout. All files have the same ROS topics (but might have different length of recordings). More advanced, I want to do it in the CI pipeline. Even though, plotjuggler is a GUI tool, I managed to do it:

• by sending keystrokes with the tool xdotool
• by using xvfb when being on the headless CI server However, plotjuggler does not display the data of the new file, so it does not work.

PossibIe Improvements

1. Fix the bug described above --> Then we can use it for automatic creation of plots, but plots it is cumbersome and brittle.
2. To easily make a screenshot automatically after plotjuggler has loaded, make a flag so that plojuggler loads without needing clicks/keystrokes. The flag should:

• Load all topics from the layoutfile (or just all)
• Display the bag with the given layout

3. However, in this way we can only create a screenshot of the first tab automatically.

• The easiest way would be to add a shortcut to change tabs (e.g. TAB). Then we can send TAB to plotjuggler and make a screenshot of the next. This would also be good for humans.

4. Maybe, there should be a option to remove the left topic component or make it smaller. It is not saved in the layoutfile. So space is wasted.
5. Ideally, there should be a command line option to create plots from files, but I guess this more involved.

Impact

• If 1) is done, it is possible to make images automatically in a brittle way.
• If 2) is done, it would be less brittle and used reliable.
• If 3) is done, layout files with multiple tabs (e.g. the original ones) can be reused. Otherwise, one has to manage multiple copies.
• 4 and 5 are just the icing on the cake but not really needed.

I guess 1) (and 2)) are easy to implement compared to 5. This would allow to integrate plotjuggler in automatic scripts, in particular in CI pipelines, where it does not matter how they look.

All in all, a few small modification would allow it to use it to automatically create plots from (simulated or real) data.

[mistermult]

I guess you and other might be interested in creating automatic screenshots. This might be relevant to #137 and #362. I do in the following way:

rosrun plotjuggler PlotJuggler -d bagfile.bag -l layout_rosbag.xml &
sleep 20
WINDOWID=$(xdotool search --class PlotJuggler)
xdotool windowactivate ${WINDOWID} && xdotool key ctrl+a && xdotool key ctrl+a && xdotool key Return && xdotool key Return
sleep 60
xdotool windowactivate ${WINDOWID} && xdotool key Return && xdotool key Return

Now plotjuggler should be loaded if there was no bug. Then, do a screenshot and end it:

scrot
killall -9 plotjuggler

If you want do do it headless, then do the following

Xvfb :2 -screen 0 1024x768x24 -fbdir /var/tmp 
export DISPLAY=:2
# Do commands as above but make the screenshot instead of scrot with
xwd -root -silent | convert xwd:- png:/tmp/screenshot.png

[facontidavide]

Please send me your lauyout.xml, I think I know what is going on

[facontidavide]

For the records, I will not work on creating this "automatic images" workflow, but I think you found a bug anyway that need to be solved.