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[Jon Hacking]

Originally Posted by transmitterdan

I think it is really important for the mbtiles folks to understand the best way to create tile sets before jumping all over the developers. There are many examples of poorly designed tile sets out there.

I don’t personally use mbtiles much. But it is crazy to me to shove 4-10GB of image data down OpenCPNs throat and then bitch about rendering speed.

A hi res screen only needs about 20MB of pixel data. Many of these mbtiles have way too much detail for the zoom level because the tile set builders are not optimizing the resolution for the zoom level.

Thanks for this, TDan (& Thomas). The way my mbTiles render isn't a problem, so I'm not sure that turning off quilting will have a significant effect, but I'll give it a try (although it would mean turning it back on to look at KAPs or CM93).

TDan, how do you think mbTiles should be designed?

Mine have multiple zoom levels, & I *assume* that OpenCPN chooses the correct zoom level for what it's trying to display. Yes, I probably could have gotten away with only using Z18 (generally the highest I go) & let OpenCPN reduce the pixels, but that would have taken much longer to make (& probably longer to render), as Sat2Chart makes the mbTiles for all zoom levels you want, & I also wanted to load up SAS's cache with zooms 10-18. A bit of a shotgun approach, to be sure, but I often don't know where I'm going to need the detail.

And, to be honest, I was cramped for time. We were back in the land of unlimited free internet for only 2 months & I wanted to make 500GB of mbTiles, & I needed to work with Paul to smooth out the bugs & add features to Sat2Chart.

I didn't mean to sound like I was "bitching about rendering speed". In fact, OpenCPN seems to render mbTiles faster than my (high res) KAPs. I can move around in mbTiles, but moving around with KAPs showing gets slow enough that I usually bail out to CM93, move, & then come back to my KAPs.

The routes I used to make my mbTiles are the same routes I used to make my KAPs. KAPs take a LONG time to make (maybe 6/min & I made 300,000) so I made those routes pretty carefully to follow the coastlines closely. I also couldn't make them too big, so they generally cover only 1 island or a small island group, & large islands are broken up into multiple stretches of coastline (max ~100nm).

[Bluechip27]

Tearing my hair out at the moment. I'm running Opencpn 4.1.1028 on a Tesco Hudl 1 running Android 4.2.2. According to the notes on Google Play this version of Opencpn should work on Android 3 upwards. Opencpn installs fine and picks up the GPS and shows correct location on the crude world map which is incorporated within Opencpn .... BUT ... when I install CM93 vector charts, no matter what I try Opencpn does not use those charts. I've installed the charts correctly by selecting the directory holding the CM93 charts and done a full data base update which takes quite a while so presumably it is doing something! I've inspected the Opencpn config file just to double check that it has picked up the correct chart directory and it has. Out of curiosity I installed the same version of Opencpn on my son's smartphone which runs a later version of Android (5.1.1) and the exact same CM93 charts and that works perfectly fine! The only difference I can see is that the installation on the Android 5.1.1 version has created an additional folder 'CM93' within the Files folder, the contents of this additional folder are files whose names end in 'coverset_sig.A' through 'coverset_sig.G'. I'm wondering if Opencpn can actually access charts on Android 4.2.2 ? Does anyone have any experience or advice please?

[Rasbats]

Bluechip27 ...

My HUDL 1 is also Android 4.2.2. Here the charts are in a folder on the external SD card: "/mnt/external_sd/CM93".

All is working fine. You need a main CM93 folder and when you add a directory to OpenCPN with the toolbox use that folder.

I don't have any files with names like "coverset_sig.A" only numerical folders under "CM93" with sub-folders "A", "C" and "Z".

Mike

[Jon Hacking]

Bluechip, when you "install CM93", what are you actually doing? The "install" should be no more than a file-copy. Note that you want to point OpenCPN at the CM93 folder, not any of the (numerical) sub-folders. It will automagically pick up sub-folders.

Rasbats Mike, thanks for the Android location. Under CM93 are a bunch of folders named with numbers, & under each of those are folders named with letters A-G. Inside those letter-folders are the actual data files, & they have filenames of ######.A to ######.G. Think of the numbers as locations, & the letters as zoom levels.

[bcn]

Bluechip...

the Android version of OpenCPN maintained by Dave (based on the actual OpenCPN 5.0.2) has no problem to manage chart directories, even in devices with Android 4.4.x or 4.x.x
This one: https://play.google.com/store/apps/d...pencpn.opencpn

What you are using is the forked one from the very beginning of the Android version of OpenCPN. From November, 3rd 2015
Nobody has never done any update, maintenance or bug corrections on that version.
It is trial&error: if it works, then ok, if not bad luck.

[spiv]

5.0.2, no SOG & COG in status bar.

After updating my Android OP, I've been playing with settings and found some great features I didn't know about.
However, somehow now I cannot see SOG & COG in the toolbar, even though I can see VMG in the route bar.

I tried for hours and read both the manual and forum posts, but I am lost [emoji30] [emoji30]
Can someone help me to restore the visibility of SOG & COG in the status bar Pkease?

[spiv]

And occasionally I get this - 0.00 kn??

[spiv]

O. O0 kn...

[spiv]

Ok, I found the fix for both problems:
I had enabled "Calculate SOG & COG from position changes" in Settings > own ship.
Disabling it restored functionality.

[Bluechip27]

Rasbats / Jon Hacking, thank you both for the replies and it's encouraging that Rasbats has it working fine on Android 4.2.2 but can I ask what version of OpenCPN are you using? Is it 5.02 rather than the 4.1.1028 which I did my testing with? I'm hoping that you are going to tell me that it's 5.02 in which case I have a simple solution, all I would have to do is upgrade to OpenCPN 5.02.

[bcn]

AO 4.1.208 does not know about plug-ins at all. But the already built-in ones.

[Rasbats]

Bluechip27 ...

AO 5.0.2!

Mike

[Bluechip27]

Thank you Mike (Rasbats), very much appreciated, now that I know that Opencpn 5.02 handles CM93 vector charts fine on Android 4.2.2 all I have to do is install the 5.02 and I'm in business.
Regards,
Mike

[Ivanm]

How can I change the colour of Ais targets in night mode to be brighter I use Cm93 Charts strugle to see targets in night mode

[Ruthlesstexas]

Hello very new to Raspberry pi and understanding the language. I’m following the steps listed OpenCpn.org and when I get to

sudo apt-get install opencpn

It says

Package opencpn is not available, but is referred to by another package. This may mean that the package is missing, has been obsoleted, or is only available from another source.

Just wanted to download the software
Thanks