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Map coordinates (georeferencing)

Put the project on a map grid such as MGA, the British National Grid or UTM, so IFC and DXF exports land where surveyors expect them.

Map coordinates tie the project to a national map grid: where its origin is in eastings and northings, how high it sits, and which way the grid runs. Exports then carry them, so a surveyor's CAD drawing or a GIS lines up with your model, and a consultant's georeferenced IFC lands in the right place in yours.

Choose a grid

Map coordinates start from the site's location, so set that first in the Site panel (an address, or the latitude and longitude). Then, in Map coordinates, choose a Coordinate system:

  • your national grid, where Stori3D knows one for the place: GDA2020 / MGA and GDA94 / MGA in Australia, NZGD2000 / New Zealand Transverse Mercator 2000, OSGB36 / British National Grid, ETRS89 / UTM in Europe and NAD83 / UTM in North America;
  • WGS 84 / UTM, which works almost anywhere;
  • Another (EPSG code) for any other grid, with numbers from a survey.

Each choice shows its EPSG code. Choose None to take map coordinates off.

What Stori3D works out

With a grid chosen, Stori3D works out the Easting and Northing of the project origin (plan 0, 0 on the ground floor) from the site's location, along with how far grid north is from true north and the grid's scale there. Move the site and they follow.

The location comes from the map, so these numbers are a good starting point rather than survey accuracy. The British National Grid also involves a change of datum, good to a few metres.

Use a survey's numbers

If a surveyor has given you the coordinates of a point you've used as the origin, type them into Easting and Northing. From then on the project keeps your numbers, and Grid north and Scale factor appear for you to enter as well. Work out from the location goes back to the worked-out numbers.

For Another (EPSG code), type the EPSG code and a Name, then the survey's easting, northing, grid north and scale factor.

Height above datum is the height of the ground floor (level 0) above the grid's height datum, usually sea level. It goes into exports either way.

Exports that use them

  • IFC: every IFC export writes the site's latitude and longitude and true north. With map coordinates it also writes an IfcMapConversion to the grid (IfcProjectedCRS), so Revit, Archicad, Solibri and BIM viewers place the model on the map. See Exporting.
  • DXF of a plan: in the 2D drawings view, Export → DXF in map coordinates (.dxf) writes the level plan in eastings and northings, turned to the grid.
  • 3D DXF: File → Export → 3D DXF in map coordinates (.dxf) writes the model's meshes in eastings, northings and heights above the datum.

Bring in a georeferenced IFC

When you import an IFC that has map coordinates (an IfcMapConversion):

  • If your project uses the same grid, the model lands where the map puts it, turned to suit, so a consultant's model lines up with yours.
  • If your project has no site yet, it takes the file's location, true north and map coordinates.

Heights still follow the file's storeys, which land on levels at the same elevation. See Importing.

AI agents

Agents can set map coordinates with the site: a grid's EPSG code, the origin's height, and a survey's easting and northing. See AI agents.

Still stuck? Contact us, or ask in the app: Help → Contact support.