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TDoA maps
Hi John,
Some observations & suggestions based on use.
Could all the green known reference location markers be shown by default on the TDoA results maps rather than just one selected marker. Very often if I'm trying to see if the results are anywhere near a known location, I have to go back to the TDoA map and then select another reference station before swapping back to the results map to see if the new selection is any closer. It would be much better if they were all shown rather, than having to second guess which one to display. The existing reference locations tick boxes could still be used to disable them if the are not required. The display would then be more consistent when switching between maps.
Could the map limits and zooms be linked so that any change to the current map is carried ever to the other maps. I quite frequently zoom or move the results map and then forget to change the KiWi TDoA selection map before I press submit. I only discover this when the results come back and the map is not centered where I expected it to be. This happens less now that the re-submit option is available, but it still occasionally catches me out. Also when the KiWI map and results maps are at different zoom and center positions, it makes it more difficult to judge which KiWi's to try next in order to narrow down the location.
Also if a KiWi that was used to obtain the results map becomes unavailable for a period (all channels in use of no GPS) it seems to disappear from the results map. This can make it difficult to decide which KiWi's to use for the next run if the original stations are no longer shown on the map. Could the original KiWi's used remain shown on the results map ? Could KiWi's that can be used for TDoA but which are not currently available perhaps be shown greyed out rather than not being shown at all ? This would allow them to still be selected (and saved in a stored URL string) for later use when they become available again. It would also facilitate (as previously suggested) a TDoA to be setup and automatically run once all the selected KiWi's become available for use.
Sometimes it's difficult to see the 'most likely position' location marker on the results map if the plots are very clean and there is no visible heatmap. In some cases the marker can be hidden by a green reference location marker. Maybe some radial distance rings could be added (as a map option) to the most likely position marker ? This would help to highlight the marker position and also quickly show how far off the TDoA plot was from a known location.
One (final) minor point, and I'm probably being too picky. But I'm not sure about the 'Submit' and 'Rerun' button titles. Maybe something like 'Sample' / 'Capture' / 'Acquire' and 'Repeat' / 'Redraw' / 'Refresh' would perhaps be more descriptive ?
Regards,
Martin - G8JNJ
Some observations & suggestions based on use.
Could all the green known reference location markers be shown by default on the TDoA results maps rather than just one selected marker. Very often if I'm trying to see if the results are anywhere near a known location, I have to go back to the TDoA map and then select another reference station before swapping back to the results map to see if the new selection is any closer. It would be much better if they were all shown rather, than having to second guess which one to display. The existing reference locations tick boxes could still be used to disable them if the are not required. The display would then be more consistent when switching between maps.
Could the map limits and zooms be linked so that any change to the current map is carried ever to the other maps. I quite frequently zoom or move the results map and then forget to change the KiWi TDoA selection map before I press submit. I only discover this when the results come back and the map is not centered where I expected it to be. This happens less now that the re-submit option is available, but it still occasionally catches me out. Also when the KiWI map and results maps are at different zoom and center positions, it makes it more difficult to judge which KiWi's to try next in order to narrow down the location.
Also if a KiWi that was used to obtain the results map becomes unavailable for a period (all channels in use of no GPS) it seems to disappear from the results map. This can make it difficult to decide which KiWi's to use for the next run if the original stations are no longer shown on the map. Could the original KiWi's used remain shown on the results map ? Could KiWi's that can be used for TDoA but which are not currently available perhaps be shown greyed out rather than not being shown at all ? This would allow them to still be selected (and saved in a stored URL string) for later use when they become available again. It would also facilitate (as previously suggested) a TDoA to be setup and automatically run once all the selected KiWi's become available for use.
Sometimes it's difficult to see the 'most likely position' location marker on the results map if the plots are very clean and there is no visible heatmap. In some cases the marker can be hidden by a green reference location marker. Maybe some radial distance rings could be added (as a map option) to the most likely position marker ? This would help to highlight the marker position and also quickly show how far off the TDoA plot was from a known location.
One (final) minor point, and I'm probably being too picky. But I'm not sure about the 'Submit' and 'Rerun' button titles. Maybe something like 'Sample' / 'Capture' / 'Acquire' and 'Repeat' / 'Redraw' / 'Refresh' would perhaps be more descriptive ?
Regards,
Martin - G8JNJ
Comments
I think I need to loosen up the criteria for "GPS is okay" so you don't have as much problem with the third issue. Same for "all channels in use".
The fourth issue of overlapping/obscured markers is definitely a problem. I like your idea of additional highlighting of the likely position marker.
And I agree about the button names..
Great, thanks for considering the comments, I look forward to trying them out :-)
Regards,
Martin - G8JNJ
Unfortunately it looks like the recently introduced Google maps free usage limit has now been exceeded and the TDoA maps have started to display the 'For development purposes only" tags on the map tiles.
Regards,
Martin - G8JNJ
I can see why that jars and other options are being considered.
They had suggested Leaflet (an open-source JavaScript library for mobile-friendly interactive maps) https://leafletjs.com/ as being worth looking at, but I'm sure there are many other contenders too.
I think this decision may actually cost Google more than they may gain in the long term, and it's not as though they really need the money either.
Regards,
Martin - G8JNJ
It also seems like there is Leaflet open source for all the Google map API packages the TDoA extensions uses: day/night overlay, marker labels, marker clustering, lat/lon graticule etc.
Can you clarify the TDoA situation for me.
Does the Google map problem actually prevent the TDoA application from working or is it just a mainly cosmetic issue ?
I ask because I've not been able to get any TDoA results back for the past couple of days, and I get the "pair contour error: zoom map in or check reception" message returned instead, although this may be completely unrelated.
This occurs even with the 'new algorithm,' and 'new map format' checkboxes unticked.
Regards,
Martin - G8JNJ
>Something else for me to look into..
>
Hi John,
Yes, sadly this seems to be the case, I think something else has broken over the past few updates.
I'm just not able to get any TDoA results back for about 95% of the time, even running some I'd previously stored in DX tags and have run perfectly several times in the past, as I often use them to test and help validate new TDoA runs, that I think may be suffering from errors due to 'unhelpful' propagation conditions.
I just wish I could provide more help, as I realise that you are up to your neck in it............
Regards,
Martin - G8JNJ
I like the new TDoA maps in v1.238, I think I actually prefer them to the original :-)
Thanks for the quick fix.
Regards,
Martin - G8JNJ
If you are using Leaflet (or even if not) these links (cribbed from another forum) may be of interest
OpenStreetMap Donations https://wiki.openstreetmap.org/wiki/Donations
OpenStreetMats Help Site https://help.openstreetmap.org/questions/
Nominatim (lookup) https://wiki.openstreetmap.org/wiki/Nominatim
Install and Host http://nominatim.org/release-docs/latest/admin/Installation/
Leaflet https://leafletjs.com/
Leaflet Marker Clusters https://github.com/Leaflet/Leaflet.markercluster
Leaflet Control OSM Geocoder https://github.com/k4r573n/leaflet-control-osm-geocoder
Loading Indicator https://github.com/ebrelsford/
Leaflet.loading Switch2OSM https://switch2osm.org/serving-tiles/
Build Tile Server https://switch2osm.org/manually-building-a-tile-server-18-04-lts/
Good procedure for setup https://ircama.github.io/osm-carto-tutorials/tile-server-ubuntu/
Map Server Setup Tasks https://meta.wikimedia.org/wiki/Maps_server_setup_tasks
Apache mod_tile https://wiki.openstreetmap.org/wiki/Mod_tile
Performance Tuning http://www.geofabrik.de/media/2012-09-08-osm2pgsql-performance.pdf
Regards,
Martin - G8JNJ