update depth_image_proc components

[mikeferguson]

This makes them loadable with the rclcpp_components
interface. I've fully tested PointCloudXYZRGB and
ConvertMetric, my use case doesn't use the others.
I also lack a setup to test the launch files fully,
but ran them with the realsense commented out and
they appear to be OK.

[mikeferguson]

CI seems to have failed in image_view -- which I'm not changing...

[SteveMacenski]

@mikeferguson yeah, you can ignore the image_view failures in the PR builder, but Circle should pass without an issue

  >>>
 
build/depth_image_proc/test_results/depth_image_proc/flake8.xunit.xml: 2 tests, 0 errors, 2 failures, 0 skipped
 
- depth_image_proc.flake8 E127 (./launch/point_cloud_xyzrgb.launch.py:67:34)
 
  <<< failure message
 
    continuation line over-indented for visual indent:
 
                                     ('points', '/camera/depth_registered/points')]
 
  >>>
 
- depth_image_proc.flake8 E501 (./launch/register.launch.py:68:100)
 
  <<< failure message
 
    line too long (105 > 99 characters):
 
                                    ('depth_registered/camera_info', '/camera/depth_registered/camera_info')]
 
  >>>
 

Looks like you need to lint a few lines. I get daily failure emails reminding me about image_view, I'm hoping to get to it this week, its an annoying boost issue I just need to sit down and play with.

[SteveMacenski]

LGTM when CircleCi passes

[JWhitleyWork]

It looks like you're missing the CMake changes necessary to support registration as composable nodes. First, the nodes have to be part of a shared library target (not an executable target). Then, you need to register them with an rclcpp_components macro:

rclcpp_components_register_nodes(library_target_name Plugin::Class::Name)

[mikeferguson]

@SteveMacenski - I'll get the python fixed up later today.

@JWhitleyWork - it's already a library and the rclcpp_components_register_nodes directives were already there. Basically, without my changes, ComponentManager could already find the library and load it, but was unable to find the plugins since they had the wrong ClassLoader directive and constructor signature (I'm guessing they were ported at an earlier time when the API of components was still volatile). I have actually loaded these plugins and used them to construct a point cloud from a Primesense camera using a horrible hacky port of openni2_camera.

[mikeferguson]

@SteveMacenski circle ci is now passing!

[SteveMacenski]

Thanks for the contribution!