On Mon, Mar 25, 2013 at 8:28 AM, Jack O'Quin wrote: > These are all good ideas. I think the original suggestion of > transmitting deltas is worth consideration, too. There are common use > cases involving large maps with only small changes being applied. > > People also need maps for multi-story buildings, hierarchical maps, > and other applications that don't quite fit the current map interface. > > The Geographic Info project has done some experimental work on > outdoor Earth-oriented maps with latitude and longitude coordinates. > While the representations and coordinates differ, those interfaces are > at least indirectly relevant. > > https://github.com/ros-geographic-info > > I suggest creating a Special Interest Group to discuss current > practices and propose extensions to the standard ROS map interfaces. > > http://www.ros.org/wiki/sig > > A SIG would probably be appropriate. However I'd suggest a more generic one such as navigation so that it can be reused going forward once this topic has been resolved. > > On Mon, Mar 25, 2013 at 9:54 AM, Damon Kohler > wrote: > > There's a basic implementation here: > > > > > https://code.google.com/p/rosjava/source/browse/google_map_transport/src/main/java/com/google/google_map_transport/MapTransport.java?repo=google > > > > In this case, I'm also scaling the image if necessary. > > > > On Mon, Mar 25, 2013 at 3:48 PM, Dereck Wonnacott > wrote: > >> Damon, > >> > >> Well, that just makes all kinds of sense, would you mind sharing your > >> implementation details? :) > >> > >> > >> I wonder if we could support this in a generic manor by adding an > 'encoding' > >> to nav_msgs/MapMetaData > > > > +1 > > > >> then nav_msgs/OccupancyGrid's data[] could be encoded in a wide number > of > >> formats. Perhaps we can use openCV to do the encoding/Decoding as well. > >> > >> This would break backwards compatibility, but it seems like the right > way to > >> go since adding the encode/decode should be a trivial fix for dependent > >> packages to come up to date.... :/ > > > > +1 > > > >> ~Dereck > >> > >> > >> > >> “The greater danger for most of us lies not in setting our aim too high > and > >> falling short; but in setting our aim too low, and achieving our mark.” > - > >> Michelangelo > >> > >> > >> On Mon, Mar 25, 2013 at 5:25 AM, Damon Kohler > >> wrote: > >>> > >>> Rather than dealing with deltas, I've been simply PNG compressing the > >>> occupancy grid data. That helps a lot. > >>> > >>> On Sun, Mar 24, 2013 at 8:58 PM, David Lu!! > wrote: > >>> > This is useful discussion topic. Some people have already been > exploring > >>> > it > >>> > with the OccupancyGridUpdate message > >>> > > >>> > ( > http://ros.org/doc/groovy/api/map_msgs/html/msg/OccupancyGridUpdate.html) > >>> > in particular Stéphane Magnenat. There was a REP partially related to > >>> > this > >>> > topic > >>> > > >>> > ( > https://github.com/stephanemagnenat/rep/blob/91dc02f8f2a82c5ef4820d2fc9f0f6d1fd1d0c20/rep-0129.rst > ) > >>> > but I'm not sure what the final status of it was. > >>> > > >>> > > >>> > > >>> > > >>> > On Sun, Mar 24, 2013 at 8:59 AM, Dereck Wonnacott > >>> > wrote: > >>> >> > >>> >> ROS users, > >>> >> > >>> >> I had an idea for improving map topics and would like to open it up > for > >>> >> discussion and get some feedback on the idea. > >>> >> > >>> >> Problem: I like to run rviz for my mobile robot on a different > computer > >>> >> than my robot for obvious reasons, but when gmapping maps get large > >>> >> they > >>> >> tend to saturate the network. > >>> >> > >>> >> Idea: Reduce the required bandwidth by publishing map deltas rather > >>> >> than > >>> >> full maps. > >>> >> > >>> >> Implementation details: The /map topic would publish the full map > and > >>> >> latch that message for new subscribers. > >>> >> > >>> >> The /map-updates topic could then publish a hash of the map being > >>> >> published on /map and a list of changes required to bring that map > up > >>> >> to > >>> >> date. > >>> >> > >>> >> When the change list size exceeds some threshold, it can publish and > >>> >> latch > >>> >> a new map on the /map topic. This will cause /map-updates to have a > new > >>> >> hash > >>> >> and clear the change list > >>> >> > >>> >> The full map could be published on /map-full for backwards > >>> >> compatibility > >>> >> with older nodes. > >>> >> > >>> >> Suggestions and feedback on the idea greatly appreciated. :) > >>> >> > >>> >> ~Dereck Wonnacott > >>> >> Michigan Tech Robotics Lab > >>> >> > >>> >> > >>> >> “The greater danger for most of us lies not in setting our aim too > high > >>> >> and falling short; but in setting our aim too low, and achieving our > >>> >> mark.” > >>> >> - Michelangelo > >>> >> > >>> >> _______________________________________________ > >>> >> 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 > >>> > > >>> > >>> > >>> > >>> -- > >>> :wq > >>> > >>> Google Germany GmbH > >>> Dienerstr. 12 > >>> 80331 München > >>> > >>> AG Hamburg, HRB 86891 > >>> Sitz der Gesellschaft: Hamburg > >>> Geschäftsführer: Graham Law, Katherine Stephens > >>> > >>> Tax ID:- 48/725/00206 > >>> VAT ID:- DE813741370 > >>> _______________________________________________ > >>> ros-users mailing list > >>> ros-users@code.ros.org > >>> https://code.ros.org/mailman/listinfo/ros-users > >> > >> > > > > > > > > -- > > :wq > > > > Google Germany GmbH > > Dienerstr. 12 > > 80331 München > > > > AG Hamburg, HRB 86891 > > Sitz der Gesellschaft: Hamburg > > Geschäftsführer: Graham Law, Katherine Stephens > > > > Tax ID:- 48/725/00206 > > VAT ID:- DE813741370 > > _______________________________________________ > > ros-users mailing list > > ros-users@code.ros.org > > https://code.ros.org/mailman/listinfo/ros-users > > > > -- > joq > _______________________________________________ > ros-users mailing list > ros-users@code.ros.org > https://code.ros.org/mailman/listinfo/ros-users >