Corner points when creating boundary

Easting is adjusted then the new easting is used to calculate the new northing. Sneaky for sure. Maybe that’s it.

yes, that is! good catch. A couple temp values with original values and you are good. It’s tricky because depending on the rotation, it may or may not affect the result.

Here is the latest. Yes, it made very little difference where it was located. Not enough to see in GE. But for sure it is close now.

public void BuildPointLATLON(double easting, double northing)
double XO = 0;
double YO = 0;
XO = (Math.Cos(pn.convergenceAngle) * easting) - (Math.Sin(pn.convergenceAngle) * northing);
YO = (Math.Sin(pn.convergenceAngle) * easting) + (Math.Cos(pn.convergenceAngle) * northing);
XO = XO + pn.utmEast;
YO = YO + pn.utmNorth;
UTMToLatLon(XO, YO);

Right on! It isn’t much of a difference, but it is wrong. Best to have it work correctly. Once the distances increase, the little bit adds up to a lot.

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Yes, I agee. Small errors can lead to big, or hard to find problems later. Thanks again for your patience and expertise.

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Built similar. The first picture shows a boundary and run with a boundary built with WalkAbout. The second picture shows a screen shot during WalkAbout record boundary. Just walk to the corners you want to record with GPS on a stick. Notice the tractor is turned off as well as the ability to run any section control. The little yellow arrow is north. The point is direct under GPS. Thought process- Head to the field on ATV with tablet and GPS on a pole. Hop off and mark the corner. Drive to the next point. etc.

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Kent, that is exactly how I’d want to survey our fields for maximum accuracy. I cheer for this feature!

Would it be possible to export a boundary run in Agopengps to a KML file, which can again be imported as a boundary, on another device? Then Agopengps would be the only tool you need to run all the farm’s boundaries and have the KML’s at hand for new devices or any other occasion in the future. It would solve my issues with getting precise boundaries into Agopengps and keeping them forever.

Yes, that is what it’s supposed to do. I’ve only tested it in the simulator. But in the simulator, you guide the point to where you want the boundary and click point. I think there is a 5 point minimum built in AOG. I’ll have to check that. But when you close the field it saves the kml file including the boundary. This could easily be set to build a separate kml file for just the boundary. Any of this can be imported into google earth or other kml readers.

I saved solely the boundary feature of a field KML you posted here Section Path to KML - Google Earth - #8 by KentStuff and indeed no problem to import as the boundary for a new field.

Then it should work. I’ll try some field testing and see what I get.
Edit: Rained all day. Have to try another day.
Edit2: Another all day rain. Maybe clearing out tomorrow.

Hi, I’m just wondering in which version is this background button?
It would be nice to have it on Github, it’s a bit confusing to have someone downloaded from telegram and some verses on gihub.

This is my local edit. Mostly un tested. It can be found as a fork under Brian’s main Github. None of these edits are in the official release.

This one?

Yes. Look on this forum for the instructions for getting the background file built. It needs to be named right and in the field folder before you click the background button.
Edit: It is in section to kml forum.

working on version 4, lots of changes like for boundary where you can add/delete single points, free record, delete the whole path and start again, set the offset of the point you want to record…

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Kind of working, but need some adjustments

looking forward to testing it :slight_smile:

Make sure that while in google earth that you set the view to straight up and north. Keyboard short cut. U and N. File, copy or save image. Then crop to the thin red line that is drawn around the field. Precision cropping is important. Looking good anyway.
Edit: Should have said to open a field that has a boundary first. Close that session of AOG. In that field directory there should be a file AOG…kml. Open that file in GE. In the left panel it should have your file. Expand it and turn off everything except crop line(or cut line, I can’t remember ). Then start your straight up and north. Copy etc.

I built a just boundary.kml and tried to import it into a new field. If I load it into GE and then save to new kml. It works fine. Just opening it I get an error. Seams AOG needs a one line coordinate list where I have multiple lines. (at least that’s what I’m guessing right now. ) Back to coding. Getting closer.
@kareldew Better. I had to write the BoundaryKML file with the coords as a single line. That was a bit tricky on my end. But yes, now you can use AOG to record a boundary, save it as a kml and import it into any new field.

Listed below is the portion of the kml writer that writes the list of boundary Lat, Lon to a single line of text. Must be a million other ways to do this but this is what I finally got to work.

string Combined = " " + bndkml[0].northing + “,” + bndkml[0].easting + ",0 ";
for (int i = 0; i < count8; i++)
Combined += bndkml[i].northing + “,” + bndkml[i].easting + ",0 ";
Combined += bndkml[count8-1].northing + “,” + bndkml[count8-1].easting + “,0”;//Close the loop

Alright, after nearly 6 inches of rain, finally tested walkabout. Worked like a charm. Just walk to the points and click point. It draws a straight line from last point to here. It also draws a dashed line from the first point, through you and back to the last point. That part works really well. I was not able to get NTRIP connected in laptop so the error is the typical 1 meter±. I brought the whole thing back inside and run the simulator the local sim cords. I then saved the field, which saves the kml file. When opening in GE it overlaid nicely. I then used the cut line to crop and save the background. Then loaded in AOG. Yeap, I’d say it works. I’ll upload a picture later.

Edit: This is without NTRIP. The line walked was on the edge of the vertical asphalt in the picture. The GPS was placed on the he fence on the right in the picture. Measuring the difference in GE is less than 2 meters. The simplicity of walking to the corners was easy enough.

Here it is in AOG. Coming from the other direction.


More Testing Today. This should have been a separate reply but discourse would not let me.

First let me preface this with I think I got the NTRIP working. I can’t tell. Now…

Been doing some testing on walkabout and flag placement and GE. Brian is correct. GE can be very far off. Just scrolling through the years you can be off by 3 or 4 meters. I have a 2004 set that is 50 meters off. Yes, Brian, that’s not a typo either. My house is actually not even in view. So, wanted to test flag to flag, or path to path. In the image below, the flags were placed before lunch and I re walked it after lunch. First was disappointed, but on investigation of the path segments they are 1 meter in length. My guess is that the fix trigger is not allowing the recording of the actual point. Brian would know more about that than I would. That being said it may be necessary to “magnify” the points during the walkabout or force a pinpoint. Probably can just get ahead of the trigger.

Back to GE and the background. Since the image can be and is off most of the time. I propose a shift background routine that you can line up and or scale the background to a minimum of three reference points. I’ll do some more thinking and testing.


Working on sliding image to match the field Lat and Lon. The little circles on the left, you just click it in the direction you want it to slide. Not nearly 50 meters but 2 to 3 meters it will. In the image below it was slid over to line up with the asphalt on the right and the fence at the top of the view. The image is actually upside down as the vehicle is driving south. But the two circles show the image needed to move up and to the left, hence the circle offset. I also used this to pan around the field while driving without the background. That worked well also.

Slide Background