Hi Tim, thanks for starting the discussion. I started a similar discussion (off-list, with package maintainers) for the case where google map or openstreetmap maps are used as background in map plots created in R, support for which is now scattered over ggmap::get_map, RgoogleMaps::GetMap, dismo::gmap and https://github.com/hadley/rastermap. (on r-forge, sp::plot and sp::spplot can now deal with these, see sp::demo(webmap)).
The (un)projection mapView does is towards epsg:4326 (longlat WGS84), leaflet assumes this and takes care of the projection to web mercator; the message printed in mapView (if verbose = TRUE) and your tutorial do the correct thing but suggest they convert to mercator. Some remaining questions: - package leaflet also supports plotting Spatial* and Raster* objects, what is exactly added by mapView? - have you thought about integrating this functionality into the leaflet R package? - could we strive towards argument compatibility, so that we can get things done by simply changing "plot" or "spplot" into "leaflet"? On 07/24/2015 11:39 AM, Tim Appelhans wrote: > Dear list members, > > I would like to draw your attention to a little 'project' I've been > working on over the past few weeks. > > Using leaflet for R, I have defined some methods for spatial data (e.g. > Raster*, Spatial* objects) to quickly visualise them in either the > RStudio Viewer pan or the default web browser. The function I created > for this is called mapView(). > > Think of it as an interactive version of spplot()/plot() for spatial > data (though less versatile). It enables zooming, paning and basic layer > queries (i.e. printing of the attributes in the @data slot of Spatial* > objects + the x/y location of the feature). For Raster* objects queries > are currently not available as leaflet translates the data into RGB > values for display. Furthermore, background maps can be defined and > multiple different spatial object layers can be overlaid. > At the moment mapView() lives in our Rsenal package on github > (https://github.com/environmentalinformatics-marburg/Rsenal) but this is > likely going to change at some point in the not too distant future. This > also depends on whether there is active interest in developping this > sort of thing further to provide more than the current admittedly rather > limited functionality. This, however, would involve JavaScript coding > which I do not have any experience with. > > A quick (non-interactive) intorduction can be found here: > > https://metvurst.wordpress.com/ > > The full introductory article including interactive examples is > published here: > > http://environmentalinformatics-marburg.github.io/web-presentations/20150723_mapView.html > > I hope this may prove useful for some of you. > Also, if anyone is keen to get involved in taking this further, please > let me know and we will see how to best proceed. > > Best, > Tim > -- Edzer Pebesma Institute for Geoinformatics (ifgi), University of Münster, Heisenbergstraße 2, 48149 Münster, Germany; +49 251 83 33081 Journal of Statistical Software: http://www.jstatsoft.org/ Computers & Geosciences: http://elsevier.com/locate/cageo/ Spatial Statistics Society http://www.spatialstatistics.info
signature.asc
Description: OpenPGP digital signature
_______________________________________________ R-sig-Geo mailing list R-sig-Geo@r-project.org https://stat.ethz.ch/mailman/listinfo/r-sig-geo