Shared Coordinates - True North

[craig.johnsonJ84C6]

Two project files, and a shared coordinates file. The project files have been linked into the Shared Coordinates file, positioned on the site plan, and coordinates published. In each project file, the positions have been acquired from the Shared Coordinates file. So far so good...

Project 1, True north is correct in the file. This project was set up a while ago, and it must have been done in the beginning before the Shared Coordinates were made. 

Project 2, True north is incorrect, and just the same as Project North.

• Should I set True North in the Shared Coordinates file? Or do it individually in each of the files (Project 1 already has this)?
• Will True North changing in the Shared Coordinates file affect each project? 

(A separate Shared Coordinates file with nothing in it has proved to be the most understandable way to manage locations. But I am still green at this, as it is a simple, but yet complicated thing...)

[Ilic.Andrej]

Sharing coordinates between two projects doesn't mean they nececarely need to have the same angle between Project North and True North. For example, the front facade of the first building faces South, while the front facade of the other building faces Southeast... In this case, you would set different Project North for each of the building projects...

[barthbradley]

I'm not following. If Projects are Shared, and the Coordinates of the Project having an "Angle to True North"  was Published to the Linked Project, then that Project should have an "Angle to True North" as well.  It is possible that the Coordinates were Published to a Site Name other that "Internal".  In the Project that you say has no "Angle to True North",  Go to Manage: Location: Site to see if other Site Names exist.  I'll bet you have one that corresponds to the "True North" of the Project it is Linked into. Make that Site Name "Current" and then toggle your Plan View "Orientation" from "Project North" to "True North".  

FWIW, I'll add that a Link Project can have many "True North" orientations by virtue of Named Sites.  It is best practice to Publish to Named Sites - not the default "Internal".  

[craig.johnsonJ84C6]

Correct, they already have different Project North's. It's just one of them, which was created first, doesn't have the correct True North.

So I wasn't sure if setting True North in the Shared Coordinates file, would change both files. Or if I should just set True North in the file where it's not set.

I guess: Will setting True North in the Shared Coordinates file mess with the True North of the two Project Files.

[craig.johnsonJ84C6]

That makes sense. I closed the projects and am busy for the next while, but will be checking that first.

[ToanDN]

You only need to set True North in the Shared Coordinates Authoring model. When you publish / acquired shared coordinates from this model to others, True North and Survey Points in those models will change to match those of the Authoring model.

[craig.johnsonJ84C6]

Thanks--this makes sense. I'll test it later.

[craig.johnsonJ84C6]

Here are the coordinates for each project.. (Altered so that you can't find me).  They were created at 2 different times, and I think we decided to make them have a Shared Coordinate system after the first was created.. They all function properly in relation to one another.  All with "internal (current)" Site. I hope this helps..

We are in early SD's and haven't brought in M/E/P/S yet. So I can abandon this--in which case--what's the best way to abandon the shared coordinates? Set everything back to 0,0,0. It's not imperative that we have them. We can work around that issue.

SHARED COORDINATES FILE
Survey Point:
N/S: 0
E/W: 0
ELEV: 0
Angle to True North: 0

Project Base Point:
N/S: -900
E/W: -600
ELEV: 208'
Angle to True North: 0

(True North in this project is not True North. True North and Project North are the same in this project. And appropriate for this project.)
_____________________________________

PROJECT 240
Survey Point:
N/S: -800'
E/W: -600
ELEV: 0'

Project Base Point:
N/S: -800'
E/W: -600'
ELEV: 208'
Angle to True North: 0.00

(True North in this project is not True North. True North and Project North are the same in this project)

_____________________________________

PROJECT 245
Survey Point:
N/S: 0
E/W: 0
ELEV: 0

Project Base Point:
N/S: -1300
E/W: -500
ELEV: 208'
Angle to True North: 49*

(True North is True North in this project. Project North has been rotated to appropriate angle for the project)

[barthbradley · Accepted solution]

This information is not relevant to Sharing.  Are all the links positioned correctly in the Parent Project(s)? If so, you are good to go. If not, move the Link to the correct position and save that new position back to the Link.  

Here's an excellent resource to read to gain a better understanding of Shared Coordinates:

https://s3.us-east-2.amazonaws.com/pfacs.downloads/Conferences/Aubin_HAND_2015_RTC_Shared_Coordinate....

[ToanDN · Accepted solution]

There is a flaw in this setup. The True North should be true in the Shared Coordinates Authoring model. If you say that an untrue True North is appropriate in that model then you picked the wrong one to be the Shared Coordinates Authoring model.

Here is the setup I would go with:
- Choose a model that the True North matter to be the Shared Coordinate Authoring. An overall Site Model is the most appropriate.
- Link your other models in the Authoring model, move them, rotate them, elevate them to their correct location, then publish Shared Coordinates to these links.

And that is it. You don't need to be worried about manually messing with True North and Survey point in any of the linked model. Their True North is true, linking one into another using Shared coordinates will place them all in the right spot. It never fails.

[barthbradley]

What's the flaw?  

The way I read it:

Project 245 is rotated 49 degrees from 12 o'clock high in the Shared Coordinates File. Project 240 is not rotated  in the Shared Coordinates File. 

[craig.johnsonJ84C6]

I accepted this solution, as I think it helps the most with the link. I have a question about starting this process over, but I guess I can start a new thread for that one? The question is if I start all over again, will it mess up anything in the models themselves--views, etc. I don't want to piss off any of my co-workers if I do anything overnight. 

I just always have hesitancy when moving the Survey Point... And I think it was moved in the 240 project a while back.

[craig.johnsonJ84C6]

@ToanDN  I like your simplification of it. If I go into the two projects, unclip and reset their coordinates to 0,0,0, and make sure True North isn't changed. Sync. Then go into the Site (I've named it Shared Coordinates), and make sure they are positioned correctly there. Publish their coordinates. Save. Then acquire coordinates in their respective files from the Site file. Would that mess up anything on the sheets/etc? (Will my co-workers notice anything regarding their views?

(I know this post is convoluted and I'm potentially in over my head here, but I'm learning, and you all are making better sense of this now)

[barthbradley]

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@craig.johnsonJ84C6 wrote:

I accepted this solution, as I think it helps the most with the link. I have a question about starting this process over, but I guess I can start a new thread for that one? The question is if I start all over again, will it mess up anything in the models themselves--views, etc. I don't want to piss off any of my co-workers if I do anything overnight. 

I just always have hesitancy when moving the Survey Point... And I think it was moved in the 240 project a while back.

---

I'm not clear why you want to start over. You can use the Reconcile Tool to Publish them to different site names, if that's what you want to do, but you don't have to move anything or "start over".  What are you trying to correct?  

BTW: you can Move the SP Marker in the Linked Projects without affecting/moving it's Origin. The SP Origin is what is being read when linking by shared coordinates.  

[ToanDN]

No issues at all when you reset the re-publish OR re-acquire shared coordinates.

But you don't publish AND acquire. Choose one or the other:
- If you link the buildings in the shared coordinates model, move them, then use Publish to save the Shared Coordinates to the links.
- If you link the shared coordinates model to the building models, move it, then use Acquire to get the Shared Coordinates from the site.

I personally prefer Acquire, especially if the models are on BIM360.

[craig.johnsonJ84C6]

@barthbradley I guess I have the thought of starting over, in order to do it again from scratch to better understand the methodology. This is a topic I've had an interest in for a while, but haven't had the opportunity to explore it in depth. Even more--apply it in a real world scenario...

[craig.johnsonJ84C6]

@ToanDN Good to know. The last I want is for someone to come in first thing in the morning and say their section/plan on the sheet no longer exists! Panic! End of the world!

I'll wait until this evening to try and understand some more about it by interacting with them. For now, they they do relate to one another correctly and Project North is correct in both. And I know, if it ain't broke don't fix it.. But I like to know how things work..