A Grand Day Out
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== Post-processing Tracks ==
== Post-processing Tracks ==
[[file:.png|]]The most interesting item on the device is the recorded track. Usually the track has a peculiar color and name when loaded from the device. Thus the first thing I do is to silence the color and to change the name. I do that by selecting the track. You can right click on the track in the list and select edit, or you click on the small profile graph in the map canvas. Either way, the track edit dialogue will show up.
Revision as of 18:01, 25 July 2011
Many people think that it needs big commercial software packages to do real trip planning. If it doesn't have a price it can't be good. Commercial software surely has it's charm. And there are quite some nice applications out there. But as usual these are Windows only and they are designed to make you spend money over and over again. I think if you are not polar explorer or the reincarnation of Indiana Jones, you get along with QLandkarte GT quite well. In the last years many features for planning a tour have been added to QLandkarte GT making it a quite serious tool for the task. Let me show you by taking you on a trip.
We are on a camp site near a small German village called Kallmünz (EnglischGerman). We had a big BBQ yesterday evening and just got sober during a long breakfast. Probably the best condition for a good walk in the woods practicing our famous hobby geocaching. But as the real nerds that we are we can't go without precise planning involving loads of hi-tech equipment. That is the moment where we unpack our netbooks an fire up the GSM uplink to get a pocket query.
To get the full cache description you select the edit icon . That will open the edit dialog for the cache waypoint. You will notice that on the main page many fields are disabled for edit. This is a cache, it's not yours, you are not supposed to edit the data. Select the "More" page and you will get the cache description.
Some of you might have wondered about the map by now. What you see is a very nice, high detail topographic map of scale 1 pixel/meter. The map can be bought from the local authorities . There is a huge variety of free online maps, too. The quickest at hand is the OSM tile map (---OSM---). See the sample below on the left hand side.
And you can use maps from WMS servers. These maps can be loaded via XML file in QLandkarte GT. As creating the XML file is a bit tricky we collected a few for you . Have a look into the files before you use them. You might want to tweak the path for the local cache. The sample on the right hand side below is from the Google Satellite  tile server.
It looks like our BBQ was too excessive and Google took the picture in a bad moment. But let's have a look at the multi level WMS map from Bavaria  that gives us a much better view on the orthographic layer (left hand side). And if you zoom out you get the topographic layer (right hand side):
Of course QLandkarte GT can handle vector maps, too. Right now Garmin's vector map format is supported. However support ends when it comes to digital rights management. But there is a huge choice of free Garmin maps based on the OSM data. The screenhot on the left hand side shows the openmtbmap Bavaria. Another nice feature of QLandkarte is the support of a Digital Elevation Model (DEM). It allows to create a relief shade over every map. For details see the articel in the Wiki . The screenshot on the right hand side gives an example.
Ok, why are we doing that anyway? Ah, yes, yes, we wanted to go for a hike with geocaches. I nearly forgot about that... That pocket query has 500 caches. Let's reduce it by selecting the caches we want to find. I do that by double clicking the icons on the map. The final result looks like that:
Now I right click on the left hand list to get the context menu again. The item "Delete non-selected" is now available. I select it to remove all waypoints that are not on our route. Next I select "Proximity" and set all waypoints to a 100m proximity alert to make my GPSr barf when getting close.
Route or Track?
Tadaa! This will give us a really miserable result. We need a Plan B.
Plan B is to draw a distance polyline. The best way to do this is using a vector map. There are two screencasts  that explain the process on details. The final result is a tour of 14.5 km and looks like that:
The guys are is still not happy. 14.5km is ok to walk in the flat. But what about the hills? I right click the distance polyline in the left hand tool view and select "Make Track" from the menu. A dialogue pops up and I select to set a trackpoint every 10m and to use local DEM data. If you have no local data attached to the current map you can load the needed data from www.geonames.org. Pressing "Ok" will hide the distance polyline, create a track and switch to the track tool view. In 14.5 km we will have a total ascend of 325m. I select the track to see the profile on the map canvas. You have to enable that feature in the system's setup menu, or you select "Edit" from the context menu in the track list.
Prepare the GPSr
I stored all geocache waypoints to the device. But as I have one of these modern units that can show raster maps as well as vector maps. I want to use the nice raster map that I own for the hike. To do so I select the map to be displayed and zoom to a fitting viewport. Next I choose "Select Sub Map" (F5) from the map menu. I use the mouse with the left button to select an area on the map. You will notice the grid. As I want to export the map as Garmin Custom Map (GCM) it is limited to 100 tiles of size 1024x1024 pixel. The grid helps you to count the tiles. You can remove/add tiles to the selection if you click on them with your mouse. I did that in the corners of the selection. Also notice that the map I use is a multi level map. It has several maps of different scale as stack displaying the map that fits the current zoom level best. However GCM only allows one level. Luckily QLandkarte GT calculates the grid and the selection for the most detailed level.
To convert the selection to a GCM I use the "Export Map" button and get the export dialogue. I setup all parameters and provide the output path and file prefix. For GCM export this is the file name of the resulting KMZ file. After I pressed "Export" QLandkarte will some magic with GDAL and a tool that comes together with QLandkarte. "--- finish ---" tells you when it's done. I copy the resulting KMZ file to the CustomMaps folder on my device.
Finally! We are done with our studious preparations. Of course we forget to carry enough water and some food. The choice to wear sneakers was brilliant for the camp site, but not for everything else we encounter this day. Anyway, around 5 hours later we reach the camp again. After a cool bath in the near by river, loads of drinking water, some food and a cool beer, we hit the netbook again.
Read Data from the GPSr
For my Garmin GPSMap62s retrieving data from the unit is as easy as writing data. I simply have to open the GPX files created by the unit. QLandkarte GT is able to open several GPX files at once, if you select several files in the file dialogue. To do so you select File->Load Geo Data (Ctrl+L). But this works only if the files are in the same folder. If you want to load more data from other folders you can use File->Add Geo Data (ALT+A) to load the files without removing the previous content loaded.
The most interesting item on the device is the recorded track. Usually the track has a peculiar color and name when loaded from the device. Thus the first thing I do is to silence the color and to change the name. I do that by selecting the track. You can right click on the track in the list and select edit, or you click on the small profile graph in the map canvas. Either way, the track edit dialogue will show up.