Does Google Navigation GPS Requires 3G to work?

[Smokeyham]

GPS Map Data

Smokey,

I admire you for asking in an old (appropriate) thread.

Yes, you are correct. Unless you have a third party application, or store your maps on the sd card there will be no maps available for the phone. The GPS component will stand alone to provide a latitude and longitude (which you will need a third paty app like GPS status to see/use easily) but the phone needs 3g or wifi to download maps on the fly.

Craig

Hi Craig,


Thanks for your kind words, and information. You also answered another question I had, which was about whether you can display your current Lat/Long even if you don't have a cellular signal.

I have downloaded the GPS Essentials App, and will be curious to try it when I am out of cellular range.

 

[Bear in NM]

Smokey,

Just remember that the phone uses assisted GPS to triangulate your position from cell towers if you have this turned on. And the phone functions as a stand alone gps unit if you have no cellular communication, or a combination of both. What the phone lacks is any kind of gps application that even remotely resembles an entry level dedicated GPS unit, like decent waypoint storage, routes tracks etc. But there are plenty in the market. I will take a look at GPS essentials, I have not tried that one. Thanks.

What has my curiosity going is whether any of these other programs can/will be able to take advantage of the new cached maps. I am guessing probably not, as most software/companies who tile maps tend to do so in a propriatary nature, but I hope I am wrong. Google + open source could mean good things.

Craig

 

[RW-1]

Question;

If it caches the maps (taking up a ton of space, but that's beside the point), what happens if you drive off-course? How big a cache does it download? Or does it do the whole country in one fell swoop?

Hey FBM, it can't be too large, or at least, too large to matter during your trip now in V5, because its not map tiles, but map data to construct it. If it did, certainly you could clear cache afterwards, etc.

But from my reading of the Google mobile blog, this rerouting thing has a few more updates to go on it.


As Bear indicated - Let's remember something agps is still gps, it uses the sat's. It will also use assisted signals from data to get a position fix more quickly, and here is the confusion - Technically it doesn't need it to get a GPS position calculation, it can do this from the sat's alone.

HOWEVER, almost all of the apps in use need the data connection to DL the map data to USE with the gps location information, hence you need both to begin a trip routing.

If you had cached maps on the phone tpo cover a route, then I believe you could get it without a 3G signal at this point, or with the next couple of updates to GMaps, since it will cache your most used area's/routes.

 

[Bear in NM]

You guys got my curiosity up, as I do not use navigation, and have been relying mostly on 3rd party apps for my gps.

Google maps still uses some type of tiling process. The tile visibility appears to be tied to the zoom level you use when scrolling around. If you zoom at a certain level, and scroll around your screen, these maps get stored at that zoom level. If you turn data off, go back into maps and visit the same spot, if you try to zoom closer you will likley see distortion, as the correct tile at the correct zoom level has not been cached. What is different is that these tiles seemed to be stored in a very few actual different file locations.

I tested loading both terrain and satellite at very high zoom values, actually max zoom, and scrolled around a very large area. Like 30 or so square miles. I think I am at 30 or so of meg's of data map cache. By traditional .jpg or .tif standards this is a SIGNIFICANT reduction in size. I have another program that I use that this measurement would be in the gig's of storage data, and in literally hundreds if not thousands of individual files. And the way that the satellite and terrain data still pops up in blocks indicates that Google is still using this type of data as a raster image, while the roads (and possibly names) appears to be vector data. I can only guess they have worked out some kind of crazy compression process.

So yes, the storage may seem kinda high, but it reality it is a major breakthrough. And with my testing to date, my suggestion for a trip would be to choose the type of data you want (sat/terrain/etc), pop into maps, zoom to the level you will want to use, and scroll around at this level to encompass the entire area you want to have available. For my work this is not a big deal, as I use other types of maps not available through google, but if you can live with google maps this is some pretty interesting stuff. I wish I lived somewhere where navigation actually worked, it would be fun to test.

Craig

 

[furbearingmammal]

It's kinda fun opening a can of worms.

I would say even 500MB of data would be a tremendous breakthrough compared to the 1GB my cheap-butt, two-year-old GPS unit uses. So, it sounds like Google is making tremendous strides in this area as well. Will be REALLY interesting to see where things go before year end. Thanks everyone! I really want to see where this leads.

 

[takeshi]

Just remember that the phone uses assisted GPS to triangulate your position from cell towers if you have this turned on.

aGPS is not tower triangulation. They're 2 entirely different things.

I tested loading both terrain and satellite

Terrain and satellite are a bit different than the maps view. IIRC the vector graphics apply to just the standard maps.

 

[Bear in NM]

Thanks, I knew I would get the technical terms buggered, but the intent, the phone has two ways to get positions sort of gets the point across.

I spent time on the google page reading what they say they have accomplished with this vector/raster thing, and it does appear that perhaps they been a little overzealous with what they say they have done v. what is in the works. Which is fine, as what they have accomplished is pretty nice. Just the cache would be great, but having the size relatively managable is pretty sweet. And I concur that the terrain and satellite data do appear to be "rastering" but as their web page states integration of the raster and vector data I still cannot tell if there is any of that going on in sat/terrain.

As I mentioned above, what will be very interesting to see if they allow ap integration with the cached imagery. Historically companies that spend resources creating these images, "stiching" them together and providing proper geo referencing are generally pretty closed when it come to integration outside their software. Hey Google, open source this I dare you...........

Craig

 

[furbearingmammal]

Wow, would that create a [family friendly forum frowns on foul language-edit]storm.

 

[takeshi]

Thanks, I knew I would get the technical terms buggered, but the intent, the phone has two ways to get positions sort of gets the point across.

More than two, actually. WiFi can be used as well.