OpenCPN Radar Overlay PlugIn

[GHammond]

Anomalies with openGL on 64 bit and 32 bit linux?

I finally got a Navico/Simrad 4G radar mounted. Plugged it into a hub. Works great. Thank you so much to the developers.

Here's the anomaly. I have 3 linux boxes (2 Thinkpads and one Intel atom board). All running recent Arch Linux. All can apparently control the radar; all can receive the disply packets from the radar (according to wireshark). Two of them (running 64 bit Arch) cannot, however, display the radar image. Only the 32 bit Arch box can display the imagery on screen. So it seems the 64 bit boxes work right up to the point of drawing the radar picture on the screen but cannot actually paint the pixels.

Note this is the BR24 plugin NOT the Gradar plugin that I'm using.

Of course there could be other differences between the boxes but I'm strongly tempted to pursue the 32/64 bit difference. All 3 boxes have standard Intel graphics hardware. I did download the multilib 32 bit intel libraries for the 64 bit boxes in case there were some calls to those libraries, but it made no difference.

The opencpn logs look much the same on all the boxes - no obvious errors.

Any ideas on how to pursue this? Are there any known issues with 64 bit openGL that would/might be a factor? Any flags that might make a difference?

I am not using any other hardware - no Navico screens or MFDs. I can supply wireshark captures or logs if any of that be useful?

The radar is a fantastic addition to openCPN. Thank you so much to all involved.

Best

Pete

[maxxflow]

Hi Pete,

I'm using the BR24Radar_pi on 64 bit Ubuntu, it works great here.

Do you get something similar to the following (repeatedly) in opencpn.log?

01:38:56 CET: Rotating image for HDT=0.000000 Correction=0 Rotation=0.000000 Result=0.000000
01:38:56 CET: max_range=1706 angle_prev=4094

If you do, you could (assuming you compiled the plugin yourself) open up plugins/BR24Radar/src/br24radar_pi.cpp, and try the following:

1. Find br24radar_pi::RenderRadarOverlay, for me it's row 823
2. A bit further down, find the following rows and comment them out, like this:
   

           // Skip angles that have not been received for three rotations. We may want to fine-tune this further.
           //if (!m_scan_range[angle][0] && !m_scan_range[angle][1] && !m_scan_range[angle][2]) {
           //    continue;
           //}

3. Further down yet, find the following, and add a line as described:
   

           for (int radius = 0; radius < 512; ++radius) {
               int red = 0, green = 0, blue = 0, strength = m_scan_buf[angle][radius], alpha;
               strength = 255; // <<----------- Add this line
               alpha = strength * (MAX_OVERLAY_TRANSPARENCY - settings.overlay_transparency) / MAX_OVERLAY_TRANSPARENCY;

...and recompile.

This is what I did to troubleshoot a similar problem, that turned out to be a network issue.
If the OpenGL rendering works, you should now get a solid red overlay all over the chart in OpenCPN.

Good luck,
Joel

[bdbcat]

Hello GRadar geeks...

Thanks to Chuck Skerry, we have a new version of the Garmin GRadar PlugIn for OpenCPN.

This is Version 1.3.

New features include:
-timed transmit
-guard zones with alarm
-selectable color scans

The Windows DLL is attached here, and the source is available at github. Consult the opencpn.org site for details.

This is very nice work, Chuck. We all seriously appreciate the coding effort involved. I look forward to testing the new features at sea.

Thanks again
Dave

[GHammond]

Dear Joel

That was really helpful - thank you.

I changed the source as you suggested and the screen did NOT draw red all over.

I then added another line of code inside the drawing code to make a log entry each time the radar tried to draw a blob to make sure that the drawing code was being called - and quickly generated a huge log which proved that the radar plugin was trying to draw blobs and they do not appear.

In other words, I did this:

                glColor4ub((GLubyte)red, (GLubyte)green, (GLubyte)blue, (GLubyte)alpha);    // red, blue, green
                wxLogMessage(wxT("Drawing blob right now"));
                draw_blob_gl(angleDeg, radius,  blobRadius, .75);

So...I think it must be an openGL phenomenon: it can't be just a 64 bit issue since you're running 64 bit so I'll concentrate on the openGL flags/switches/variables.

The only other anomaly I can see by comparing the logs from the working box with the non working is that the non working box always reports max_range as 0 -- like this:

10:48:51 SGT: Rotating image for HDT=0.000000 Correction=0 Rotation=0.000000 Result=0.000000
10:48:51 SGT: max_range=0 angle_prev=4095

Not sure if this is material.

If any one has any ideas I'm all ears...

Thank you Joel

Pete

[rontom]

Hello

I have been trying to steady my Boat down when i am using Radar overlay at slow speeds, I purchased a Digital Yacht fluxgate compass to help compensate for the Pitch and Yaw in rough weather, The fluxgate is communicating with the Computer alright, it shows magnetic heading in the magnetic heading window in the opencpn program, but it does not slow the boat motion on the computer screen down, so the targets and the Beach are pitching and yawing with the Boat at slow speeds.
The Gradar works fine at 7 knots, its when i get below that speed is when things worsen.
I don't know if i have the compass is hooked up right, or is all the right input is going into the computer, I have included some screen shots of the NMEA Debug window, Hope somebody can tell me by looking at them if i am doing it right, or some input would be appreciated. also these screen shots were taken at the Dock, not underway, i had the screen dimmed down because it was still dark at 7am.
The Fluxgate compass came with a Tera Term program to speed up or slow down the in put, but i do not want to use it unless i have to.

Thanks
Jim

[ChuckSK]

Jim

The gradar_pi uses true heading HDT to align the image with the display. If HDT is not available, course over ground COG is used. Your fluxgate compass is providing a magnetic heading HDM from the HDG message. So COG is being used for alignment.

If a magnetic variation value is available, ocpn will calculate HDT from HDM + Mag Variation. If you install the WMM_pi it will provide the mag variation.

Check in the gradar log to see if the HDT is being received.

Chuck

[rontom]

Thanks Chuck

I am going out fishing tomorow, i will have a chance to play with it, I really like the GRadar, just at low speed i have problems.

Thanks
Jim

[BMD21]

I'm going to upgrade the boat's radar after the first of the year. The 2 choices are the new (yet to be delivered) Garmin xHD18 or the B&G 4G. And I've read every message in this forum. And I'm confused about using a 4G radar. I'd like to reduce my confusion before I buy one or the other.

Now the questions.

For Garmin, it looks like everything is straight forward. I've downloaded Gradar and it's a matter of getting the radar plugged in. I understand that.

It turns out that the B&G 4G is not too much more than the Garmin will be, and on the small boat we have, I really don't use anything more than 10 nM, mostly on the way to Santa Cruz Island, so the close in resolution would be better for us. However, I'm not certain of the status of the 4G plug in. I understand that several people have used it and are thrilled. I've been to the github page and to be honest, I haven't compiled a program since the '60s, using the yellow brick road.

So could someone provide the detailed steps for incorporating BR24radar_pi into openCpn? Do I have to compile a specific version of openCpn? So the radar overlay isn't a separate add-in? Does someone have a compiled version I can download? Do I have to recompile every time I upgrade openCpn? Remember ver. 3.3 is on the way.

Is there a way to get a radar image by itself into a PC running Windows? Even if not using openCpn?

Boris

[BluegillBoy]

I too would like a summary! i'm about to buy a 3G (good enuf for me, and cheaper) but want to make sure i can can get it going with OCPN. likewise, i'm not a compiler, just a user.

Boris, here's some outside info that might help as well:

OpenBR24 | Free software downloads at SourceForge.net
OpenBR24 - shown working without a nav program, and alos with what looks like google earth?? this URL is the early version of OpenBR24 that was 3G specific, but perhaps the info applies to the new 4G version as well.

And this one
Panbo: The Marine Electronics Hub: Radar on your PC, laptop or tablet
saying there was a beta plugin as of last January.

[Helmsmatt]

Hi Dave,
We just installed the Garmin HD radar head. We're trying to download the new version 1.3 plug-in you mention, but can't find it anywhere on the OpenCPN site. We see a file in your post but it downloads as a PDF. We tried to change the file name to end in dll but that did not work.
Help?
Thanks,
Matt

[bdbcat]

Matt...

Lets see your OpenCPN logfile, please.

Thanks
Dave

[Helmsmatt]

Hi Dave, thanks for the quick reply.
I don't think I'm ready to bother you yet. We haven't wired the network cable to the PC yet, just downloaded the version 1.2 plug in. It seems to work as well as it can without the scanner connected. Our issue is that the only place we can find the version 1.3 dll is on the forum, and our PC considers it a .pdf. OpenCPN doesn't recognize it as a .dll, so won't show it as a useable plug-in. Could it be a typo in the forum? The version 1.2 .dll worked fine.
Give me a couple of days to install the network cable and scanner power-up switch. I'm sure I'll have questions and maybe you can help me locate a working version 1.3 .plug-in.
I really would like the features that the new version enables.
Thanks,
Matt

[AISEAG]

Originally Posted by Helmsmatt

... locate a working version 1.3 .plug-in.
...Matt

Hello Helmsmatt,

You should be able to get this version here : Opencpn Beta File Thingie

username : rguser
password : rgpass

and have a look on the 3.3.1117 directory;

Serge

[GHammond]

Boris...

How to install the B&G/Navico 4g radar plugin.

I don't use Windows. That said, here is the high level overview.

1. You download the source code for openCPN somewhere on your computer.

2. You will find that the source code includes a folder that is called "plugins". You will find some plugins already in there by default.

3. You change to that folder in a terminal window/command box and you use git to download the additional source code for the radar plugin. This is extra source code beyond the normal opencpn source code. You will then have an extra folder inside the plugin folder containing the 4g source code.

4. THEN you compile the whole lot - the basic openCPN plus the additional plugin.

5. This gives you a version of openCPN with the 4g radar plugin functioning.

6. Yes, you will need to recompile every time openCPN changes enough to warrant it - this isn't a big deal after you've done it a couple of times.

7. Right now the 4g plugin is very much Alpha code and the standalone radar display is commented out and non functional - it will ONLY work as a chart overlay.

As far as I know compiling on Windows is more complex than on Linux (which takes me less than 5 minutes) and requires software that you might not have - see the standard instructions:

Compiling - Windows | Official OpenCPN Homepage

An alternative, which will probably make you groan, is to consider, at least briefly, a so called "live" version of linux on a usb stick onto which you could compile the linux version of openCPN. All of the needed software is then free. You could use this on the same computer that you use windows on without altering your normal installation. This may be more work than you want if you're not already familiar with linux....

Hope this helps you to make a decision. I have a B&G4g and it works pretty well - even though the software is unstable and has very limited functionality right now.

Before you buy anything you can try compiling the basic program + the 4g plugin. If you simply can't do it then you will be able to eliminate that possibility and simplify your decision...

Pete

[rgleason]

I'll be darned, the file is there! I just checked.