Hallo Sabrina, Dejan, Jack and Michael, thanks a lot for the help and the explanation! Regards David 2011/4/6 Dejan Pangercic : > Jack, Michael, > > this of course makes perfect sense - thanks a lot for the clarification. > D. > > On Wed, Apr 6, 2011 at 12:15 AM, Michael Ferguson wrote: >> The issue is that TF output is streamed to each node, and is buffered in the >> listener -- if you create the listener inside the callback, you have no >> history of tf data before creation -- which means you often can't find the >> lookup you desire. >> >> -Mike >> >> On Tue, Apr 5, 2011 at 6:10 PM, Jack O'Quin wrote: >>> >>> On Tue, Apr 5, 2011 at 5:05 PM, Dejan Pangercic >>> wrote: >>> > Hi Sabrina, >>> > >>> >> you should instantiate the TransformListener outside the callback: >>> >> >>> >> tf::TransformListener *tf_listener; >>> > this is very interesting. But do you know why would it be necessary to >>> > have it outside the callback? Is there a documentation about this? >>> >>> I believe the destructor for the listener will shut down the connection. >>> >>> Many ROS interfaces use the RAII approach. >>> -- >>>  joq >>> _______________________________________________ >>> ros-users mailing list >>> ros-users@code.ros.org >>> https://code.ros.org/mailman/listinfo/ros-users >> >> >> _______________________________________________ >> ros-users mailing list >> ros-users@code.ros.org >> https://code.ros.org/mailman/listinfo/ros-users >> >> > > > > -- > MSc. Dejan Pangercic > PhD Student/Researcher > Intelligent Autonomous Systems Group > Technische Universität München > Telephone: +49 (89) 289-26908 > E-Mail: dejan.pangercic@cs.tum.edu > WWW: http://ias.cs.tum.edu/people/pangercic > _______________________________________________ > ros-users mailing list > ros-users@code.ros.org > https://code.ros.org/mailman/listinfo/ros-users >