How to automatically get the measurement units in Grasshopper/Rhino

How to automatically find out if your Rhino document is set to millimetres or metres:

private void RunScript(ref object scale)
  {
    int rtnval = 1;
    Rhino.RhinoDoc  doc = Rhino.RhinoDoc.ActiveDoc;
    Rhino.UnitSystem  system = doc.ModelUnitSystem;
    if(system.ToString() == "Meters") rtnval = 1;
    else rtnval = 1000;
    scale = rtnval;
  }

This script returns a value of 1 if the document is in metres, or 1000 otherwise. (I assume that the user will only be using mm or m.)

To use, create a C# component in Grasshopper and copy the part between the curly brackets to the code of the C# component. Make sure that the component has an output called ‘scale’.

…or download the component from below:

Download