SCALGO Live Documentation

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User Interface - ´╗┐Coordinate Systems

Coordinate system selection in the User menu

For country-wide setups, SCALGO Live by default uses the coordinate system used by the main elevation model available for the specific country, i.e.:

  • Denmark: ETRS89 / UTM zone 32N
  • Sweden: SWEREF99 TM
  • Norway: ETRS89 / UTM zone 33N
  • Finland: ETRS89 / TM35FIN
  • Great Britain: British National Grid
  • Poland: ETRS89 / Poland CS92

This is to ensure that the analysis is done directly on the raster elevation data made available by the national authorities, and the results you see on your screen match this data one-to-one.

To interact with other coordinate systems, SCALGO Live has the following features and options.

Point query results, profile exports, and coordinate look-up

The coordinate system used for showing the results of point queries etc. can be set in the User menu in the top-right side of the screen. This also controls the coordinate system used for looking up coordinates input into the Address search bar, and when exporting profiles in a tabular format.

Note that this is not always the same as the default coordinate system for the country.

Export map

Images and PDFs generated through the Export map function always use the country-specific default coordinate system mentioned above. This cannot be changed. PDFs exported using the "Advanced" mode include georeferencing information supported by various tools to place the document correctly in relation to other georeferenced data.

Download data

Reprojecting data on download

When downloading data using the Download tool and when downloading watershed areas, you can choose to either leave the data in the original coordinate system (this is the default), or to reproject it to another coordinate system of your choice. For vector data, reprojection does not have a big impact on accuracy, but raster data will (necessarily) become a little blurred when reprojecting it.

Dragging in vector data

When dragging vector data such as Shapefiles onto the dock, they are automatically reprojected to the country-default coordinate system mentioned above, so it shows in the right place with respect to other data in SCALGO Live.

This requires that the vector data is georeferenced (e.g. for Shapefiles, make sure to include a .prj file along with the .shp, .shx and .dbf files when dragging it in).

Workspaces from imported raster data

When creating a new workspace from imported raster data, the computations on the workspace will be done in the coordinate system of the raster data (to prevent loss of accuracy), but the results will be displayed in the country-default coordinate system.

Workspaces from LandXML or point cloud data

When creating a new workspace from LandXML or point cloud data, the data will be reprojected to the country-default coordinate system.

Uploading new raster data into an existing workspace

When uploading new raster data into an existing workspace, you can choose whether to keep the existing projection, or switch to the projection of the imported data.

See also the manual entry for Importing existing terrain data.

EPSG codes

To input custom coordinate systems for reprojecting data on download, or when creating a workspace, SCALGO Live uses EPSG codes. These standardized codes generally help in using the same definitions across different software packages, and are simple to input. In case you don't know the EPSG code for a projection of interest, you can look it up in online databases such as epsg.io or spatialreference.org.