Accurate location of projects in real world coordinates is critical when dealing with multiple disciplines and software platforms in a project. We always kick off a project in the right place and often are the first to model up project boundaries and setouts for use by the rest of the project team. So it has to be right.
We will often receive a point cloud and then need to link into Revit accurately and make sure we can do it repeatedly. If we also have a geolocated cadastral survey drawing this becomes pretty easy. But what to do if the survey is using a different projection or doesn’t have any geolocation information at all? This happens often for us to so when we need to have geolocated coordinates for our site this is one of the workflows we use.
Go to landgate https://map-viewer-plus.app.landgate.wa.gov.au/index.html
find site then select button, choose points only, draw rectangle and confirm points you want are cyan.
Once you have selected all the required points hit the menu dots and view the points in the Attribute Table.
Then select export selected to a CSV file. This is a Comma Separated Values text file that we will convert in Excel
To open the CSV file in Excel.
- Open Excel.
- Click New, then click on Blank workbook.
- Click on the Data tab.
- Click Get External Data From Text.
- Navigate to the CSV-formatted file saved on your system, select it, then click Import (When browsing to find the file, set browser to look for All Files or for Text Files)
You should then see the points in each cell and can see the coordinates system used in the column headers.
Fire up Autocad and you can use each of these to draw a point or line start and end in autocad to get a geolocated boundary line to use 😊
Once you have your Cadastral file saved you may link in a point cloud with the same coordinates system and it should match up perfectly.
You can now link the cadastral boundary file into Revit and once you have located in the correct position to your building model you may inherit coordinates from the linked cadastral file.
Point Clouds that you then link to Revit should drop into the correct place when linked using shared coordinates.