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Is there a way to move a GIS stake to a defined co-ordinate position? 

 

For example, with a normal stake, you can place a stake, and then amend the X, Y details to move it to an accurate position.

Can you do the same with a GIS stake, to identify a particular co-ordinate position, i.e. 257850E, 667750N (British Grid) - without having a line or point on the drawing already in this position to snap to? 

 

 

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First set your file to use OSGB 36 Datum, Then set the origin (search for) 49ºN, 2ºW (this is British Grid Origin) and it will set the point. You can also go to the File Georeferencing dialog and set the coordinate points of 49, -2 there also.

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@bgoff Thanks @bgoff  - I've already set my file to use OSGB 36 and the origin is set, the file is accurately positioned and georeferenced.

 

My question is about whether or not I can position a GIS stake point by typing in the co-ordinate, or if point and click to position is the only method? 

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@lisagravy I was just on with Tamsin, I now better understand your question on how you are using it there. I will research this and I am positive Tamsin will have an answer for you locally. 

 

As for moving the stake, it can be moved but only using LAT/ LONG not to be moved by Meters X/Y. To move use the "Set Location" Button at the bottom of the OIP for LAT/ LONG. To move by meters in an x/y fashion it cannot do that (or at least I haven't figured it out yet).

 

Hope this helps.

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27 minutes ago, lisagravy said:

@bgoff Thanks @bgoff  - I've already set my file to use OSGB 36 and the origin is set, the file is accurately positioned and georeferenced.

 

My question is about whether or not I can position a GIS stake point by typing in the co-ordinate, or if point and click to position is the only method? 

Hi again Lisa

Yeah - Bryan and I talked and discussed your requirement in a bit of detail.

If you are using Long and Lat within your geographic coordinate system, then the answer is YES! You can use the Set Geolocation button on the Object Info palette, with the stake selected (You can also do this with the Modify > Move > Move Geographic menu option). However, if you want to work in Easting and Northing, in Meters (as I know you do!), then it doesn't offer that option. I am going to check with the developer whether the X and Y coordinates would help, but given that X and Y generally remains true to the original equirectangular non-georeferenced coordinate system, I believe the answer will be no. But I will confirm. 

 

But I think being able to move to a specific Easting and Northing in meters would be a really nice enhancement.

 

Have not forgotten your other question which came through on email - and I'm getting you a definitive answer!

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Thanks @Tamsin Slatter - I guess.... (possibly incorrectly?!) that if I move the User Origin back to British Grid origin 0,0 after geolocating my file - by firstly defining it's current Easting and Northing position via GIS stake, and then moving it to the negative X and negative Y values of this - this sets my X and Y values to be the same as the eastings and northings? And then I could use the X Y positions of the GIS stake to move? 

 

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16 minutes ago, Tamsin Slatter said:

being able to move to a specific Easting and Northing in meters would be a really nice enhancement

Yes! I would love to see an implementation of this as well, so fingers crossed.
 

Little bit of trivia as to why this "might" be difficult. The Minute ticks along the Northings equate to 1 nautical mile, so this conversion is reasonably easy to do... But the Eastings Minute ticks do NOT equate, as they get closer together the nearer to the poles you are...
This might introduce errors going from N/E to X/Y in metres, but I'm sure the programming wizards should have a way forward.

Thanks @lisagravy for raising a brilliant question!!! Looking forward to a definitive answer!!

image.thumb.png.78274cb3d2bef561fb55a48fc7c9aaa2.png

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1 minute ago, lisagravy said:

Thanks @Tamsin Slatter - I guess.... (possibly incorrectly?!) that if I move the User Origin back to British Grid origin 0,0 after geolocating my file - by firstly defining it's current Easting and Northing position via GIS stake, and then moving it to the negative X and negative Y values of this - this sets my X and Y values to be the same as the eastings and northings? And then I could use the X Y positions of the GIS stake to move? 

 

The problem with that is that X and Y will never completely match Easting and Northing when the geographic coordinate system is active. You can use the Great Circle tool to look at the difference. For example, draw a 50m length line with the Great Circle and then it will give you the true length of that line in Easting and Northing. They will be slightly different. So, even if the User Origin is aligned to the origin of the British National Grid (off the Scily Isles), there will still be differences between X and Easting and Y and Northing.

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12 minutes ago, Tamsin Slatter said:

The problem with that is that X and Y will never completely match Easting and Northing when the geographic coordinate system is active. You can use the Great Circle tool to look at the difference. For example, draw a 50m length line with the Great Circle and then it will give you the true length of that line in Easting and Northing. They will be slightly different. So, even if the User Origin is aligned to the origin of the British National Grid (off the Scily Isles), there will still be differences between X and Easting and Y and Northing.

 

Thanks @Tamsin Slatter ! I've had a quick play with the Great Circle tool and a read through of @RussU 's post, and I get what you mean! Can see a difference of around 7 or 8mm over the 50m section I've tested. I just wasn't sure if because British Grid is a projected grid system it would have worked locally or not.

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Sorry to continue this @Tamsin Slatter, but actually the discussion on the X&Y / E&N discrepancy has actually raised another couple of points for us!

 

My (albeit limited!) understanding of British National Grid is that the Eastings and Northings are projected flat and are equally spaced, which is how we used them before accurately just by referencing X and Y? I did a test where I imported a DWG file not geo-referenced, and checked an X Y position on a standard stake, and then imported a georeferenced version of the same file to check the Eastings and Northings of the same point on a GIS stake, and I get the same answer from X,Y to E,N.

 

If X and Y will never completely match Easting and Northing when the co-ordinate system is active, how does this work in terms of us actually drawing information?

 

For example, should we still be drawing accurately using the standard poly line / arc tools etc, and lengths and dimensions as we did before? Would you ever draw with Great Circle? 

 

Also - a lot of our 2020 files have an active geographic co-ordinate system turned on as default (before we really understood what this was)... we've been using these files as per our existing workflow, i.e. X & Y as British Grid, ignoring all the georeferencing settings. (Though to be fair the georeferencing tick box on all the layers is disabled.) Will this affect any of our dimensioning on these files? 

 

Edited by lisagravy
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@RussU It depends on the project really? The drawing I have open is just under 1km square. I need to be able to provide a contractor with co-ordinate points for that, usually set out to the nearest millimetre? (Some other drawings are obviously much smaller!)

 

Edit: I typically work in Scotland, and British Grid origin is south west England so in terms of X, Y distance from user origin 0,0, this can be X: 300000m Y: 800000m, which would relate to British Grid Easting 300000, Northing 800000m, if that makes sense? 

Edited by lisagravy
Adding in origin information
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Hi Lisa

 

So, that's correct - and actually answers your other question too.

If you import the DWG into the standard X and Y coordinates with no georeferencing, and make a note of the coordinates of a known point, then repeat the test with a georeferenced file, then the coordinates of that point SHOULD match in X and Y and E and N. In the georeferenced version of that import, the X and Y coordinates in the original file have been projected into the georeferenced version of the coordinate system. The benefit of this is that you can combine GIS data (such as Shapefiles) with traditional X and Y CAD data.

Before Vectorworks 2020 - it was very difficult to combine the two. Because you could not import the DWG into the Georeferenced coordinate system.

 

So, your X and Y file should definitely match the E and N file.

However, once you are working in a georeferenced file, my point is that you should use the E and N only, as these will be the accurate numbers. The X and Y in such a file is no longer relevant.

 

It is my belief that should you then export these E and N coordinates back to DWG, they will give accurate X and Y for the recipient, even if they have no knowledge of or GIS capability - but I do want my genius colleague who developed all this to confirm that.

Hope that makes sense!

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Ok, Let me wrap my head around this over-night and have an answer (I hope) tomorrow.
I too deal with sites several km long (not very wide but very long) so the contractors do want GPS setting out data.... but then the installers want the dims in mm.

 

You have raised an excellent point here

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Thanks @RussU - much appreciated.

 

Also thanks @Tamsin Slatter - I have tested exporting the georeferenced file to DWG and reimporting in a non-georeferenced file, and it doesn't maintain X, Y co-ordinates unfortunately.

 

I think the reason is that if you geo-locate, and effectively move the user and internal origin to the project location, the export retains the X, Y position relative to this origin point. If you didn't geolocate it might retain the X, Y co-ordinates, but then we would obviously have issues with functionality of the file? The only way I can get it to work is by geo-locating, but then moving the user origin back to the equivalent of British Grid 0,0. Then the X, Y in the file looks to be representative of the E, N values... and exports and imports again ok.

 

But I don't want to start doing this if there are issues with it I can't see... 🙈 

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3 minutes ago, lisagravy said:

Thanks @RussU - much appreciated.

 

Also thanks @Tamsin Slatter - I have tested exporting the georeferenced file to DWG and reimporting in a non-georeferenced file, and it doesn't maintain X, Y co-ordinates unfortunately.

 

I think the reason is that if you geo-locate, and effectively move the user and internal origin to the project location, the export retains the X, Y position relative to this origin point. If you didn't geolocate it might retain the X, Y co-ordinates, but then we would obviously have issues with functionality of the file? The only way I can get it to work is by geo-locating, but then moving the user origin back to the equivalent of British Grid 0,0. Then the X, Y in the file looks to be representative of the E, N values... and exports and imports again ok.

 

But I don't want to start doing this if there are issues with it I can't see... 🙈 

I am checking this out for you Lisa... I will let you know as soon as I get the answer. 😀

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@Tamsin Slatter Thanks! I do get that typically when you are in a georeferenced file you want to be working with the projected co-ordinates (E, N) and ignore the X, Y as irrelevant.

 

Just thinking (hoping!) that specifically for British Grid, as the projected co-ordinate system is actually projected flat onto an equally spaced grid of metres, in this particular case the X and Y might also remain reflective of the projected Eastings and Northings when displayed in metres? (as it would obviously make my life much easier 😂)

 

Thanks for checking it out.

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Yes - that's my understanding too. They won't match while you are working in a Georeferenced file, but when you export back to DWG, the E and N should just unwrap to boring old X and Y. I'm just testing a couple of things... Hold that thought. 

(We are all going to need a large glass of wine/whisky tonight!)

 

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So my testing with British Grid so far is that the E and N don't unwrap back to X, Y if you have geolocated the georeferenced file to move both origins to the project data - they relate to the new X, Y positions relative to the origin, which don't relate to anything.

 

BUT, if you move the User Origin in the geolocated file relative to British Grid 0,0... and then check the X,Y positions of a GIS stake which shows the E, N positions, I can get my X, Y to match E and N, and export to DWG perfectly? 

 

But yes, my mind is a bit fried by it all, a large glass of wine / whisky is required! 

Screenshot 2019-10-21 at 17.21.33.png

 

(Also note for this that the co-ordinate precision is set to 0.0001m)

Edited by lisagravy

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😂 Thanks! 

 

Also should say - I found this relevant resource on the Vectorworks University site (though it is American). 

 

https://university.vectorworks.net/mod/scorm/player.php?scoid=196&cm=302&currentorg=articulate_rise 

 

The first section relates to 2019, which is different so don't watch it because it's just confusing 🙈 but have a look from 22:45 mins into the video, to around 29 mins in, where they seem to manually set the user origin to match the geo-referencing co-ordinate system... which apparently is due to be an automatic option in SP2?

Edited by lisagravy
Added video link!
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Morning all.

I have had a chat with our engineer and done some more testing myself.

 

For the British National Grid, if you align the User Origin, with the Easting and Northing Origin within the Geographic Coordinate System (EPSG code 27700 - the default in the UK templates), CAD drawing within that coordinate system will have the correct X and Y coordinates on export to DWG. So, if you are sending stuff back to someone who has no concept of GIS systems and their software does not use it, this will be fine.

 

The issue currently, within SP1, is that there is not easy way to align the User Origin with the Geographic Coordinate System, because you can't see it and there is nothing to snap to. But there is a way to do it (details below). Even better though, from SP2, there WILL be a way to do this within the Tools > Origin > User Origin command (thank you engineering team!)

 

Here's how to do this in SP1:

  1. Open a UK template - this will already have the default EPSG 27700 code to set the geographic coordinate system to British National Grid.
  2. Set the Document Units to Meters, with an appropriate precision.
  3. Import your DWG using the Document Contains Georeferenced Geometry option on the import dialog. This will import the DWG into the geographic coordinate system. Also import any Shapefiles if you are using those.
  4. Use the Geolocate tool to move the INTERNAL origin close to your geometry (just click on the drawing). This will not change any coordinates with in the Easting and Northing coordinates - it simply ensures that the geometry is close to the internal origin and avoids the traditional problems with any CAD system of placing a huge calculation burden on the system with every move of the mouse.
  5. At this point, the User Coordinate System (User Origin) and the rulers will not show anything relevant. Don't panic!
  6. Choose Tools > Origin > User Origin and choose the option to set it by next click. Click on the Internal Origin, to align it with the Internal Origin. (Again, don't panic - this is temporary!)
  7. Use the Stake tool and place a Stake on the Internal Origin (and User Origin). Set it to display Coordinate Point (E,N) in Meters with full precision.
  8. Make a note of the E and N numbers from the Stake (screenshot, write it down, or ungroup it to get the text - whichever method you prefer).
  9. Now change the X and Y coordinates of the Stake to match the E and N, but with a negative. For example: If E is 10000 and N is 5000, set X to -10000 and Y to -5000. This will move the stake to the origin of the Geographic Coordinate System, and give you a valuable snap point.
  10. The Stake should still be selected, so click Fit to Objects to find it.
  11. Now run Tools > Origin > Internal Origin again and choose again the option to set it by next click.
  12. Click on the Insertion point of the Stake. The User Origin is now aligned with the Geographic Coordinate System. The rulers will show relevant values.

Using the above method, I was then able to draw new stuff over my DWG, and then export the drawing back to DWG. I then imported it into a blank file WITHOUT using the Document Contains Georeferenced Geometry option, and all was good. The coordinates of the site matched, and the size and position of my new stuff also matched.

 

I do hope this helps clear up confusion and doesn't add to it!

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