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 .