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2020-07-22 09:51:14 -0600 asked a question 3D point cloud / mesh reconstruction of object

3D point cloud / mesh reconstruction of object Hi! I am looking for a solution to create a "complete" point cloud / mes

2020-07-22 09:49:50 -0600 asked a question Point cloud / Mesh reconstruction of an object

Point cloud / Mesh reconstruction of an object Hi! I am looking for a solution to create a "complete" point cloud / mes

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2015-12-08 08:37:42 -0600 commented answer Change focal point in Rviz automatically

Hmm..then I am afraid I am stuck here. I would not know how to extend the package to fix my problem.

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2015-12-08 07:34:50 -0600 commented answer Change focal point in Rviz automatically

Ah, restarting Rviz did the trick. Setting the focus point works, however, "eye" gets set all the time as well. This is counterintuitive unfortunately, because things like zooming by the user are senseless now :( How can I set eye to the value the user specified?

2015-12-08 07:07:54 -0600 commented answer Does a callback complete before being called again?

Oh, I guess if a program is single threaded a callback can only be called one by one.... My bad!

2015-12-08 07:07:10 -0600 commented answer Does a callback complete before being called again?

Hey! I saw the question you linked before, but I must have missed "Single thread spinner: the default one, takes the messages contained in a callback queue and process the callbacks one by one while blocking the execution of the thread that called it." Thanks!

2015-12-08 06:39:23 -0600 commented answer Change focal point in Rviz automatically

Thanks! I have written a publisher, publishing on a topic with message type view_controller_msgs::CameraPlacement. But this topic does not show under the "Type" field in Rviz View Panel. If I start CameraTest from the examples, nothing happens as well. What am I missing?

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2015-12-08 06:26:49 -0600 asked a question Does a callback complete before being called again?

Hi!

Suppose I have a subscriber with a callback C. C manipulates a number of global variables and then calls a second method M, that builds a message from those global variables and publishes the message.

I am now wondering: Is is possible that C and M interfere, i.e., that M uses global variables that have been modified by a different call to C? Or, stated differently, is it possible to call C before the previous call to C has returned?

I was not able to figure out if ros::getGlobalCallbackQueue()->callAvailable blocks till completion. If interference in this situation can happen, how does one usually deal with it?

Thank you!

2015-12-08 02:22:30 -0600 commented answer Change focal point in Rviz automatically

Thanks! I have installed the package and had a look at the examples. I believe I could achieve what I am looking for by setting the focus point. 1. Are there examples in C++? 2. Once I publish cameraPlacement messages - how can I tell Rviz to deal with them accordingly?

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2015-12-07 10:11:41 -0600 asked a question Change focal point in Rviz automatically

Hello!

I believe the focal point of a view in Rviz is the point the camera rotates around. How can I set the values for the focal point automatically? Say I have a node which is publishing the center of mass of a point cloud and I want my view in Rviz to rotate around that point - how can that be achieved?

Thanks! Jay

2015-12-07 09:58:15 -0600 commented question Coloring of pcd-pointcloud in Rviz

The only (rather unsatisfying way) I have found so far is to write an own pcd-file reader that puts the pointcloud into a pcl::PointCloud<pcl::pointxyzrgb> object. Still hoping for a better solution here!! ;-)

2015-12-07 09:27:19 -0600 commented answer (Rviz <-> point cloud from pcd) transformation

I ended up using the static_transform_publisher, I did not know about that one yet :)

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2015-12-04 04:17:32 -0600 asked a question (Rviz <-> point cloud from pcd) transformation

Hi!

I am reading in point clouds from *.pcd-files and am visualizing them using RViz. Unfortunately, the point cloud is weirdly oriented:

Look here (the "right" side of the point cloud is actually the floor)

I believe that this is because ROS uses a different coordinate system than PCL (or at least than how these pointclouds have been recorded). How do I display my point cloud correctly?

After reading through some tutorials I think I need to implement a tf-broadcaster that transforms between a "world" frame (ROS coordinate system) and a "pcd" frame (coordinate system used in my files). Then I can set the world-frame as fixed frame in Rviz and as a transformation for the PointCloud2 display my broadcasted transformation. Is that correct? Or is there a more elegant way of getting Rviz to display the point cloud "correctly"?

Thanks!

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2015-12-04 03:16:47 -0600 commented question Coloring of pcd-pointcloud in Rviz

Looking again, the issue should have been resolved on 6th of Aug (I am not really familiar with the issue-tracking system of github). I tried to confirm that I have the fixed version by checking the "Modified" date of point_cloud_common.h in my ros-folder (which is 06.August.2015). Fix did not work?

2015-12-03 09:12:29 -0600 commented question Coloring of pcd-pointcloud in Rviz

this seems to be related with the fact that my pointcloud contains rgba and not only rgb. Indeed, the latter case works. According to https://github.com/ros-visualization/... this is a known issue. Is there a way to resolve it by now?

2015-12-03 02:48:59 -0600 asked a question Coloring of pcd-pointcloud in Rviz

Hi!

I am very new to ROS, so please take that into account when answering :) (Ubuntu 14.04 64bit in a VirtualBox with Windows Host, ROS Indigo)

What I did:

I used

rosrun pcl_ros pcd_to_pointcloud myFilename.pcd 0.1

to publish a topic containing my pcl-pointcloud as a PointCloud2 message. The output of this call is:

[ INFO] [1449049889.334492450]: Publishing data on topic /cloud_pcd with frame_id /base_link. [ INFO] [1449049889.438294770]: Loaded a point cloud with 307200 points (total size is 4915200) and the following channels: x y z rgba.

As one can correctly see, the pointcloud also contains color information. I now tried to visualize the point cloud using Rviz. For this purpose I set the Fixed Frame to "/base_link" and added a "PointCloud2"-Display whose topic I set to "/cloud_pcd".

Problem description:

I was only able to see the point cloud when setting the color to something else than RGB8. Why? There should be color information and I'd like my point cloud nicely colored :) How can I fix this?