Migrate turtle_tf2 tutorial package to ROS2

[kurshakuz]

Functionality is the same as presented in http://wiki.ros.org/tf2/Tutorials/Introduction%20to%20tf2.

The only difference is that it is needed to launch turtlesim world, broadcaster and twist publishers separately from the teleop node. Corresponding issue is available here: ros/ros_tutorials#125

To launch that example, run following commands:

$ ros2 launch turtle_tf2_py turtle_tf2_demo.launch.py
$ ros2 run turtlesim turtle_teleop_key

For Rviz part in the end, run (will need to update the path):

$ ros2 run rviz2 rviz2 -d $(ros2 pkg prefix --share turtle_tf2)/rviz/turtle_rviz.rviz

[kurshakuz]

@ahcorde can you suggest what should I use for the version tag? Previously it was 0.2.3.
In addition, should I change files in the main geometry_tutorials folder? Its run_depend, license and version tags should probably be updated too.

[ahcorde]

Don't worry about the version, these packages will be release in ROS 2 for the first time. We can start with the version 0.0.0

[ahcorde]

In addition, should I change files in the main geometry_tutorials folder? Its run_depend, license and version tags should probably be updated too.

You should update both package.xml to include the <run_depend>s. for example:

• turtle_tf2_launch should include: launch_ros and launch
• turtle_tf2 should include: rclpy tf2_ros_py, geometry_msgs, turtlesim

[audrow]

Looks good overall. I agree with @ahcorde's comments.

In your Python files, it would be great to add comments for what things do. This will help check your understanding and can be something you leverage when writing tutorials.

[audrow]

One quick comment.

[ahcorde]

@kurshakuz you should also need to modify the metapackage https://github.com/kurshakuz/geometry_tutorials/blob/ros2/geometry_tutorials/package.xml

[kurshakuz]

@kurshakuz you should also need to modify the metapackage https://github.com/kurshakuz/geometry_tutorials/blob/ros2/geometry_tutorials/package.xml

fixed now

[audrow]

What you have here looks good to me.

I'm not sure what all should be included in this PR. If it's much more, we should retarget this to another branch (probably on your fork) and then make smaller PRs to that branch. Then when that's ready, we can make the PR targeted for ros:ros2.

It would also be nice to have a checklist for all of the files you plan to add; perhaps in a PR's description.

[kurshakuz]

What you have here looks good to me.

I'm not sure what all should be included in this PR. If it's much more, we should retarget this to another branch (probably on your fork) and then make smaller PRs to that branch. Then when that's ready, we can make the PR targeted for ros:ros2.

It would also be nice to have a checklist for all of the files you plan to add; perhaps in a PR's description.

Understood. Let's then merge that PR and I will push further update PRs to my own branch.

This PR mainly include:

• tf2 broadcaster
• tf2 listener
• static tf2 broadcaster

Broadcaster and listener nodes are used for the demonstration capabilities of tf2 as described in ros2/ros2_documentation#1628. More in-depth explanation of the code will be covered in further tutorials 1, 2. The static broadcaster will also be described in separate tutorial 3.

[audrow]

Looks good to me overall. I think it'd be nice to add some formatting tests.

[audrow]

Looks good after a few copyright year changes.

[kurshakuz]

All fixed now.