Fix bug in visualize constraint edges.

[kehanXue]

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Basic Info

Info	Please fill out this column
Ticket(s) this addresses
Primary OS tested on	Ubuntu
Robotic platform tested on	gazebo simulation of turtlebot

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Description of contribution in a few bullet points

Fix bug in visualize constraint edges. The old code only add the last two edge markers in visualization.

Description of documentation updates required from your changes

N/A

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Future work that may be required in bullet points

N/A

[malban]

I don't think this fix is correct.

The edges_marker and localization_edges_marker are type LINE_LIST, and contain all of the respective edges. Each pair of edge points is pushed onto the respective marker and they aren't cleared. Adding the marker to the marker array each iteration should be unnecessary and will hugely duplicate the edges.

If there is a bug in the visualization, it seems like it would be something else. Do you have any more details, like a before and after screenshot?

[kehanXue]

OK, I will give the screenshots tomorrow. I got off work today. It seems significantly different for me.

[malban]

@kehanXue I do see there is a bug where the edges_marker and localization_edges_marker are given the same marker id, which means one will overwrite the other in rviz. Originally they had different namespaces, so the id's didn't conflict. Maybe this is what is causing what you are seeing.

I'll make a MR to fix.

[malban]

@kehanXue when you get a chance could you try this branch and see if it fixes the issue: https://github.com/SteveMacenski/slam_toolbox/pull/515

[SteveMacenski]

515 merged. I'll leave this open in case it doesn't work for @kehanXue but I suspect it will

[kehanXue]

It works. Thanks. I have a misunderstanding of the MarkerArray.