Finalize tf2 migration

[rhaschke]

This is the only blocker for the upcoming Noetic release (cf. #1498).
I started the migration process as follows:

• Update InteractiveMarkerDisplay (8995e37)
• Replace deprecated getTFClient() with getTF2BufferPtr()
  • in TfFrameProperty (03a732f)
  • in TfDisplay
  • in InteractiveMarker
  • in LaserScanDisplay
• Use (already migrated) MessageFilterDisplay for all remaining displays:
  • GridCellsDisplay, which manually reimplements the logic of a MessageFilterDisplay
  • EffortDisplay, which uses MessageFilterJointState, a custom re-imlementation of tf::MessageFilter
• Adapt FrameManager and VisualizationManager to use tf2_ros::Buffer.
• Remove all tf1-related, already deprecated functions.

Any help is highly appreciated, @jschleicher or @simonschmeisser?

[simonschmeisser]

I tried a bit but found no easy translation for tf->getLatestCommonTime this is all deprecated and/or private in tf2

I managed to port LaserScanDisplay easily, so here is a PR rhaschke#2

[rhaschke]

I think I finished the migration. An open question is how to handle tf_prefix. I removed it, but probably we should keep it in RobotModelDisplay and EffortDisplay. Opinions?

[simonschmeisser]

Great job Robert! I'll look over it tomorrow.

I know that the XACROs in ROS-I contain a prefix parameter for the purpose of multi-robot systems. But I would expect this to work without an additional prefix in RobotModelDisplay? Maybe @gavanderhoorn knows more?

[guihomework]

I hope I got what is meant in the open question. We use this tf_prefix in ROS-I in the RobotModel display.

https://github.com/ubi-agni/agni_robots/blob/kinetic-devel/agni_description/config/tactile_display_both_fixed.rviz#L215

this is in order to have a specific display on a specific prefix that contains TF that are not moving (for fixing the posture of our robot hand for nice display), while still using the same urdf model as for the "moving" robot.

[gavanderhoorn]

I know that the XACROs in ROS-I contain a prefix parameter for the purpose of multi-robot systems. But I would expect this to work without an additional prefix in RobotModelDisplay? Maybe @gavanderhoorn knows more?

The $prefix you are referring to is only present at the xacro level. It's a standard approach to avoid link/joint/etc clashes when combining multiple xacro macros with others.

tf_prefix does make it easier to work with such xacros, but in the end these are not really related.

[gavanderhoorn]

As to the removal of tf_prefix from all of these displays: I'm not very happy about it, but it is true that tf_prefix has been deprecated for quite some time now.

But it's a bit strange to deprecate something and then not provide an upgrade path or alternative. Many of the paragraphs / wiki pages about the deprecation of tf_prefix end with sentences such as (this one from here):

The development time for these tools unfortunately has not been found yet.

[rhaschke]

I will keep tf_prefix, but not relying on tf1.