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Offline maps way too small !?

Richard R

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Using Mavic 3 with RC Pro Controller both with latest firmware updates. Offline maps is a great addition but even though you can visibly select a slightly larger area, the actual saved area is tiny. This makes it difficult to cover larger areas you may wish to fly in. You have to download overlapping small areas and hope there are no spaces 😞. As with Google offline maps, you can select and save large geographic areas. Most of us have enough memory with SD cards so cannot see a logical reason for this..
 
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Desperately waiting for a solution to download maps for an entire country or world. Let me know if you figured out.
 
Desperately waiting for a solution to download maps for an entire country or world. Let me know if you figured out.
DJI are aware but who knows if they will fix it. It’s mostly unusable at moment.
 
I have a 1 TB Micro SD card in my DJI RC
Ok then.

I downloaded a map of my country a few years ago - not any DJI map though, just a standard WMS protocol tiles which can be then used for `mapserver` or merged together and opened with `QGIS`. I used a few scripts I found on Github. The source of the maps was Geoportal, and resolution was 25 cm/px. It took considerably more than 500GB actually, but you can reduce that if you download lower resolution - many services don't even provide 25 cm/px, but only 1 m/px.

You just need to figure out which service you want to download from, and then prepare a script which does that. I finally switched to using `gdal_translate` to download only the areas I'm interested in rather than the whole map. And the command `gdal_translate` don't tend to change often, so my scripts from a few years ago would probably create a a good map today (this way I can get an updated map every few years). This gives a TIFF file which can be opened in QGIS without any additional processing (if you use `-of GTiff`). You just need to find (or write) an XML file which described the service you're downloading from.

And if you mean downloading for the Dji Go app - that would require writing a simple app which uses the same map API and creates the large cache, then copying that cache to Dji Go - a bit more work, but nothing an IT student can't handle.

EDIT:
Also worth noting that every map service has a specific license. You're typically not allowed for commercial use of the data you've downloaded for free.
 
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Ok then.

I downloaded a map of my country a few years ago - not any DJI map though, just a standard WMS protocol tiles which can be then used for `mapserver` or merged together and opened with `QGIS`. I used a few scripts I found on Github. The source of the maps was Geoportal, and resolution was 25 cm/px. It took considerably more than 500GB actually, but you can reduce that if you download lower resolution - many services don't even provide 25 cm/px, but only 1 m/px.

You just need to figure out which service you want to download from, and then prepare a script which does that. I finally switched to using `gdal_translate` to download only the areas I'm interested in rather than the whole map. And the command `gdal_translate` don't tend to change often, so my scripts from a few years ago would probably create a a good map today (this way I can get an updated map every few years). This gives a TIFF file which can be opened in QGIS without any additional processing (if you use `-of GTiff`). You just need to find (or write) an XML file which described the service you're downloading from.

And if you mean downloading for the Dji Go app - that would require writing a simple app which uses the same map API and creates the large cache, then copying that cache to Dji Go - a bit more work, but nothing an IT student can't handle.

EDIT:
Also worth noting that every map service has a specific license. You're typically not allowed for commercial use of the data you've downloaded for free.
In rereading my comment I realized it sounded a bit pretentious. I needed an SD card for the RC and the only one I had was the 1 TB SD b bought from Amazon for $150 that I used to transfer a bunch of media files for work. I find it incredible that a thing the size of my thumbnail can hold an entire terabyte of data. I don't even know if the RC can fully use an SD that big.
I am disappointed about the low resolution of the offline maps. Completely unusable for me - just a sea of a single green color with no marks, features, or landmarks at all in my area when I zoom in. I live in the middle of a heavily forested rural area with no cell service at all. I was hoping to use satellite maps as a reality check when setting up waypoint missions at home to fly the perimeter of my property and the like. I had hoped to use Litchi - which I'm familiar with from my Phantom days - but there's no SDK, and the RC apparently can never be used with 3rd party apps, no satellite view (offline, at least), and now, no useable 2D maps. But at least the DJI RC can do waypoints now. I guess I'll just have to set up all my waypoints by flying them manually.
 
So ,
I managed to find a way to download larger map potions , by triggering what I call the square bug . Takes me under 1 minute to trigger it .

However ...... . DJI limits the size of the offline map directory to 1GB . And 1GB for openstreetmap png data is just nothing .

To give you an example .
A tiny tiny piece of 1 small country is already more than 1GB and over 10000 files . Largest size rectangle I was able to download was 67000 png files , being 4GB .
Yes all of these files are kept in 1 directory , so if you have your card formatted in FAT32 .. you are hitting the hard limit of the filesystem by downloading a tiny tiny section of a very small country !

Onto the next .
Once you reboot the RC controller , you get the following :
- the offline map is not in the list anymore , despite all the files being there
- profile - storage - sdcard . cached offline maps does not show any MB anymore (not 0 , just shows nothing) .
- trying to download any other portion of a map simply hangs the app and you will get a message if you want to wait or close .
- screenshots now often end up corrupted . either a message "couldnt save screenshot" or it saves but the image is partially broken .

So basically , even though you can download larger maps , it is completely unworkable on the DJI RC controller .

The fundamental issue here is the use of openstreetmaps in my opinion . Their system (or at least the DJI implementation of it) , is not made for this purpose .
Downloading 1 full country would be so many png files in 1 directory that you will even hit the filesystem limit on exfat (4.7 milllion files) . And even if it would stop at 4.6 million files , and DJI would lift the 1GB limit , would the DJI RC hardware and software actually be able to handle that amount of files ?

Next .
I tried using DJI pilot 2 to download maps , but it is a completely different format than on the DJI RC controller . And hence you can not transfer anything between the 2 systems .

Very sad story and very customer unfriendly and practically unusable maps implementation if you ask me .
 
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Just joined this forum after seeing this thread in a google search for any options to the crap-map issue. Even went to map-tiler to see If they are aware of issue with DJI controllers. A fellow air 3 ownwe with the RC2 bought an RC-N2 controller on Ebay. Owner apparently totaled his new drone without insurance and decided to leave the game. Waiting for the buyer to bind the new screenless controller to the air 3 and report back. DJI wrote in early Sept that they expected to make the RC-N2 controllers available for sale in October, but time is running out . Quality drones and section 8 maps.
 
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