Topography Rotated incorrect with option from file

[Anonymous]

Hi,

I have a model that is orientated 'by shared coordinates'in RD-new for the Netherlands

When i import a file that has the ground contours to make a mesh the angle is incorrect.

Even when i use true north. Please supply the correct steps to import this in a correct way.

[barthbradley]

Have you previously rotated the toposurface to the correct position AND orientation relative to the Project North (the Orthogonal View)? You need to do that  before you set up shared positioning between the 2 files.   

The procedure would be to Link the Topo into a Project North view and manually rotate the Topo. Its rotation in the Project will be equal to the Project's Angle to True North.  After doing that, you would save the position by Publishing or Acquiring Coordinates to/from the Link.  

[Anonymous]

I don 't understand, no linking is used. I shoul clarify my problems a bit further maybe. What is have is a CSV file that contains typical survey points on national grid and level. The format is readable and has this format:

45,67,34

85,67,78

Etc.

These points now can be used in a (single) revit model to create a topo object (under tab ribbon massing and site). But before i use this my rvt file should be made 'compatible' to read them the right way so that the surface is made on the right spot. This means shared coordinates an north direction should be correct as in 'the real world' But somehow, this not seem to work the way it should.. 

[SteveKStafford]

I'd tackle it this way.

Create a separate site model

Create a toposurface using your points file

The finished surface should be oriented correctly with True North "UP" and at the site surface elevation relative to zero (sea level).

Save the model

Assuming your building model is built using a Project North, where the top of a plan view is not True North.

Link the Bldg model into the Site model

Move, rotate and elevate model to the correct position

Publish Coordinates

Save the Model > Choose Save when prompted to save changes to bldg model.

In the Building model a plan view assigned to True North should "rotate" the building to match that of the True North orientation in the site model. In other views assigned to Project North the previous orientation you used to create the model should be shown.

If you link the Site model using By Shared Coordinates it will land in the correct position relative to the building.

You should also find that if you change the Type parameter Elevation Base for your Levels it will display the Shared Coordinate elevation (sea level reference value) instead of a Project Elevation of zero.

[barthbradley]

Okay, so you are creating Topography from a Point File. Basically the same procedure as I mentioned above. You need to manually rotate the Toposurface to the correct orientation in the Project -- just as you would for any element you placed in your project. 

...Note that the Point File is x,y,z data -- not bearings.  

@Anonymous: Can to post your CSV?  I curious about what's going on in your bottom screenshot. I'm referring to those weird "rays" emanating from the Toposurface and all converging on one point.    

[barthbradley]

Actually, @SteveKStafford, in this case, wouldn't the workflow be:

1. Create the  CSV TopoSurface in a fresh Project (both Project North and True North at default 12 o'clock)

2. Link Topsurface into Building Project

3. Rotate Toposurface to correct orientation relative to Building.

4. Acquire Coordinates.  

???

...if True North is necessary in Building Project - Angle to True North would equal the rotation in step #3.  

[SteveKStafford]

Either "direction" will work, Revit doesn't care.

Acquire if the site is linked to the building and Publish if bldg is linked to the site. I'm biased toward reality - building is built on site...site is not built on the building. As such I favor building (linking) the building to the site model.

If the project is hosted on BIM 360 then only Acquire is an option so site to building is necessary or Specify Coordinates at Point.

[Anonymous]

"I'm biased toward reality - building is built on site...site is not built on the building. As such I favor building (linking) the building to the site "

If the coordinate systems are right linking would be fine. I will check if this helps. In general, i must say Revit is a pita bigtime in coordinat systems. Sorry for my conclusion.

---

[SteveKStafford]

I don't struggle with it at all but I work with lots of people that do so I get it. I suppose its similar to how math is easy for some people but complete gibberish to other people?

My problem with working with a points file is there is rarely any reference to the building so the resulting topography has no reference markers to use for building positioning. It would help if you're careful to include one point in the file that does represent a building corner, it will just be tricky to find it. That's why I prefer to have a survey file with contours that has a property boundary as well as other site related features to reference. If you have a survey based on the same coordinates then it is easier, we just have to move both the surface and survey together (when linked to a building) or they just line up in the Site model and the survey DWG provides the references to locate the building properly.

[Anonymous]

Not math, it is to many parameters that influence the placement. Could be a hell of a lot easier if Autodesk would bring in some logic in these two. In essence there are only two: translation + rotation. I have been working with software that have just this.

[SteveKStafford]

Well that's how I feel about that other software 🙂

[barthbradley]

@Anonymous: Honestly, I'm not so sure the struggles you are having are due to Revit.  Could be CSV file.  I few posts back, I asked if you could post it for us to inspect.  If you could post the RVT as well as the CSV; that would be great.  We might discover a cure for your frustration.  

...BTW: were you provided any other information with the CSV?  

[Anonymous]

The CSV is a export from the dutch national GIS database for groundheight for the Netherlands (AHN). The points where made after determinating contour lines with a interval of 100 mm as DXF. I don't believe Revit can import any other way than DWG or CSV points. Thanks in advance for any further insights is the highly complex theorie of different ways for manipulating coordination points and helping in my struggle.

Some files to get your head around. Stipped models and a screenshot.

https://we.tl/t-q4sV56na2G

[SteveKStafford]

I've linked the DWG file you shared into a Site Model and acquired coordinates. I created a toposurface based on it. I linked your Stripped model into it and moved it to what I guess it should go on site. I then used Publish Coordinates and renamed the location. In your Stripped model I linked the site model using By Shared Coordinates.

I didn't use the CSV for the above, it didn't seem necessary. If I create a toposurface using it and set the units to millimeter it is consistent with the toposurface that is created via the DWG file.

DOWNLOAD LINK to files

[barthbradley]

.

[Anonymous]

The objective is to make a toposurface based on csv. I dont want to use linked dwg because of the limitations.

To illustrate the issue i will make a short screencast later on. That might help for you to understand.

[barthbradley · Accepted solution]

What limitations are you taking about?  The ACAD file you posted today contains the information you need to create a Toposurface using Import Instance method.  It works fine.  Why do you need to do the Toposurface via the Point File method? I'm guessing it's going to create the exact same Toposurface.  No? 

...the attach RVT contains 2 Toposurfaces overlapping each other. One was created from Import Instance, and the other from the Point File.  What's the difference?

[barthbradley]

Okay, so I did find some slight differences. Perhaps the CSV reflects the most current grading. Attached RVT has only one Toposurface. It was created from your Point File. Coordinates were pulled from the AutoCAD drawing you provided us today.

[Anonymous]

What i meant with linking DWG is the method of creating a mesh in Autocad or Civil3D and using this as reference. Revit has a hard time working with others them rvt itself. However, your method to create a toposurface directly from the linked contours works so much better than importing CSV points. Thanks!

[dennis.huisman]

Nou are right Hans, I had the same  issue.

The problem seems the linked topo interacts as a model, not as a toposurface.

(You can see the linked topo wil move with the other models when you change the location, this should not be the case with a topography) I gues this is coused by the different approach between civil and architectural modelers (civil don 't use location only 1coordinate, arch uses one location per building).

I choose to create a location for the linked topo and use it as a link in my overall coordination model (which is an empty model only for geo-location and linked models).