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Locus, A GPS Mapping Application – Part II: Maps



Continuing on with my review of the Locus GPS mapping app for Android (Part I on the interface is here), today is map day. Locus has a strong selection of standard online map sources, roughly 30 vs. roughly about 20 for OruxMaps. Some are worldwide, others regional. These mapsets currently include:

  • Google Maps: Road, Aerial, Hybrid, Terrain, Korea
  • OpenStreetMap” Classic, Cycle, Transport, Osmarender, OpenPiste
  • OVI-Nokia map:Classic, Satellite, Terrain (Locus is the only app I’ve seen so far with these useful mapsets)
  • Yahoo: Classic, Satellite
  • Bing: Road, Hybrid, London A-Z, OS Maps
  • OSM-regional: UMP-pcPL, Hike&Bike
  • Freemap (Slovakia): Car, Turistic, Cyclo, Aerial
  • Yandex (East Europe): Classic, Satellite
  • Eniro (North Europe): Classic, Aerial, Nautical, Hybrid
  • MyTopo (USA): 1:24K topographic maps
  • Outdoor Active (Germany, Austria, South Tyrol)
  • Statkaart (Norway): Topo, Raster
  • Maps+ (Switzerland): Topography, Terrain
  • NearMap (Australia): PhotoMap, StreetMap, Terrain

 

While there is a reasonable amount of overlap in mapsets between the two, each one also has unique mapsets as well. For US users, the big difference is that Locus comes with the MyTopo USGS 1:24K topographic mapset built in, while OruxMaps doesn’t. You can add Terraserver topo maps to OruxMaps (more on this in a bit), but the MyTopo set is of higher quality, and some areas are more up-to-date.

 

The list of available online maps can be brought up with the map manager button, in the upper right of the main map screen. You’ll get a list of available online mapsets:

locus_mm_0

Mapsets are organized into groups by source, a better system than OruxMaps’ sequential list of all maps. If you tap on a source name, like Google …

locusmaps_2

 

… you’ll get a subset listing of all the available maps from that source. Tap on the map type to go back to the map view, and load that selected mapset. The listing scrolls horizontally, so if you can’t see the desired mapset, tap and drag the listing left or right to access it.

First time I tried using Locus in the field, I was shocked at how many mapsets I was unable to download, despite having a good cellular connection. Then I explored the Settings section; under the Map subsection of Settings, you’ll find  a setting called “Offline mode”. If this is checked, which appears to be the default, maps can only be downloaded to your unit when you have a WiFi Internet connection. This protects you from being surprised with massive data overage charges from your cellular provider if you don’t have an unlimited data plan; my plan is unlimited, so I left this unchecked, and all mapsets now downloaded properly.

As online maps are downloaded, either from a WiFi or cellular connection, they are automatically cached so that you don’t have to repeatedly download them. I presume the size of the cache is limited, and that older maps are deleted automatically, but I wasn’t able to find out this info. For longer-term storage of mapsets, and avoiding large data downloads over cellular connections, Locus lets you create mapsets from download data, and then load them as needed into the app.

select_option

To access this function, go to the “Download map” tab in the map manager. You’ll have several options for selecting the area you want maps for:

  • This screen – Downloads maps for the area currently visible in the main map screen. You’ll want to zoom in/out first to your desired area.

select_area

  • Select area – Choose a subset of the current map area by clicking and dragging; press on the green check button at the bottom to approve the selection, or the red x button to clear it and select a different area. You can zoom in/out in this view, but if you haven’t already selected the desired general area first, new map data will not be loaded in as you zoom in/out.
  • By state – Downloaded predefined areas. By “state”, this means “country”, not “US state” or other subregions. Fine for smaller countries at lower zoom levels, not great for larger countries.

map_points

 

  • By path – This is pretty slick. Select this option, and get the map screen, with a new toolbar near the bottom. Click the “+” sign to add a point at the center of the screen, then drag the map to the next location and add another point. Locus will define an area around that point for which it will download maps, and show that as a purple overlay. You can set the width of the area with the slider at the top, and also tap-and-drag points to adjust them. The “-“ sign removes the last point, while the red x deletes all points. When done, tap the green check box. Be sure to disable the button at the lower-right, as otherwise the map will keep popping back to your current GPS location.
  • Select POIs – If you have a set of waypoints loaded into a category (more on this in the next post), Locus can use those to define an area for maps to be downloaded for. Nice, but I wish there were a comparable option for tracks as well, similar to the “By path” option, but loadable from a GPX file.

zoom_levels

Once you’ve made any of your area selections, you’ll get a screen with the available zoom levels for that map; you need to choose at least one. You can choose more, but it will make the map filesize larger; maximum allowable filesize is 2 GB. The total map size and tile count is shown at top right, and you’ll also see a preview of the highest zoom level maps at right. Label the mapset file using the text box at the top.

change_type

Tapping “Change type” to choose the type/location for the downloaded map files. You can either put the map tiles into the standard online map cache, create a new separate mapset, or add maps to a pre-existing mapset of the same type. I usually use “Separate map”, since I think it will minimize complications, but that’s just a guess on my part. Once you’ve selected a map type, you go back to the zoom level screen; tapping OK starts the download process. This is usually best done with a WiFi connection, as that will be much faster, and won’t count against any cellular data quotas.

user_maps

 

Once complete, the new mapset will appear in a listing under the “User maps” tab; just tap on the mapset you want to select it. Generally, these maps work fine, but I sometimes noticed when scrolling the map that tiles would appear and then disappear for no discernible reason. However, when using the maps in general GPS navigation mode, this didn’t seem to be a problem.

As with OruxMaps, you can also create mapset files from online map sources with the free Mobile Atlas Creator software, setting Big Planet / RMaps SQLite as the output format; the app author has more info here.

So far, Locus is superior to OruxMaps in handling online/offline maps. But it falls short in two major areas:

- Adding new online map sources is more complicated in Locus than OruxMaps (although neither is easy). There’s a post at the Locus forum on the process, but I couldn’t find any actual working examples. In contrast, OruxMaps offers a sample wms_services.xml file to get you started, which adds Terraserver US topographic maps to the list of available maps, and the OruxMaps forum has more working examples.

- OruxMaps has a stand-alone desktop application that can convert georeferenced raster image files, like GeoTiffs and OziExplorer map files, into an OruxMaps-compatible mapset. There is no general tool like that for Locus; there’s a mention in the forum of an old utility that can convert OziExplorer map files, but the format it creates may be deprecated soon in Locus. And it doesn’t look like the utility program mapc2mapc currently creates Locus-compatible map files, either. So there isn’t currently a good way to get your own maps into a Locus-compatible format, and that’s a big drawback for me.

Coming up in part III – tracks and waypoints in Locus.


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1 Response to “Locus, A GPS Mapping Application – Part II: Maps”


  1. 1 Charley

    Still no geospatial PDF support…bummer!