Measure the distance of a polyline in three dimensions

Summary

The measure tool only measures polylines on a plane. You can measure a polyline in three dimensions with the script provided in this document. You must have the Spatial or 3D Analyst extension loaded in order for this operation to work properly.

Procedure

1. Open a new script window.
   
   
   A. Activate the Project window.
   B. Click the Scripts icon.
   C. Click New.
   
   
2. Copy the code into the new script window.
   
   

   Code:
   '-- This script uses an active grid theme and a polyline graphic in your view. 
   '-- It calculates the 3-dimensional distance of that polyline using the values of 
   '-- the grid cells as a base.  
   
   theView = av.getactivedoc 
   if (theView.Is(View).Not) 
   then 
   MsgBox.Info 
   ("The active window must be the View", 
   "Please try again") 
   exit 
   end 
   theDisplay = theView.GetDisplay 
   theDistUnits = theDisplay.GetDistanceUnits 
   theMapUnits = theDisplay.GetUnits 
   if (theDistUnits <> theMapUnits) 
   then 
   MsgBox.Info 
   ("The View's Distance Units and Map Units"+NL+ 
   "must be the same. Go to View Properties"+NL+ 
   "and check it out.","Please try again") 
   exit 
   end 
   theGTheme = theView.GetActiveThemes.Get(0) 
   if (theGTheme.Is(GTheme).Not) 
   then 
   MsgBox.Info 
   ("The active theme must be a GRID theme", 
   "Please try again") 
   exit 
   end 
   theSelGraphicList = theView.GetGraphics.GetSelected 
   theNumSelGraphics = theSelGraphicList.Count 
   if (theNumSelGraphics < 1) 
   then 
   MsgBox.Info 
   ("You must first have a graphic selected.", 
   "Please try again") 
   exit 
   end 
   if (theNumSelGraphics > 1) 
   then 
   MsgBox.Info 
   ("You must have only ONE graphic selected.", 
   "Please try again") 
   exit 
   end 
   thePolyline = theSelGraphicList.Get(0).GetShape 
   if (thePolyline.Is(Polyline).Not) 
   then 
   MsgBox.Info 
   ("The graphic must be a single Polyline.", 
   "Please try again") 
   exit 
   end 
   thePointList = thePolyline.AsList.get(0) 
   
   '-- Initialize the counters 
   
   measureCount = (thePointList.Count) - 2 
   trailLength = 0 
   birdLength = 0 
   startMark = 0 
   endMark = 1 
   
   '-- Calculate the distances 
   
   theGrid = theGTheme.GetGrid
   for each i in 0..measureCount 
   av.ShowMsg("Calculating Trail Distance...") 
   av.SetStatus((i/measureCount) * 100) 
   p1 = thePointList.Get(startMark) 
   p2 = thePointList.Get(endMark) 
   v1 = theGrid.CellValue(p1,(Prj.MakeNull)) 
   v2 = theGrid.CellValue(p2,(Prj.MakeNull)) 
   len = p1.distance(p2) 
   rise = (v1 - v2).Abs 
   hypo = ((len^2) + (rise^2)).sqrt 
   trailLength = trailLength + hypo 
   birdLength = birdLength + len 
   startMark = startMark + 1 
   endMark = endMark + 1 
   end 
   
   '-- Display the results 
   
   birdLength = birdLength.SetFormat("d.d").AsString 
   trailLength = trailLength.SetFormat("d.d").AsString 
   av.ClearMsg 
   av.ClearStatus 
   if (theDistUnits = #UNITS_LINEAR_FEET) 
   then theUnits = " feet." 
   elseif (theDistUnits = #UNITS_LINEAR_METERS) 
   then theUnits = " meters." 
   else theUnits = " map units." 
   end 
   MsgBox.Info("This is the distance of your trail:" 
   +NL++NL+"2-dim distance:"++birdLength+theUnits+NL+ 
   "3-dim distance:"++trailLength+theUnits, 
   "As the crow flies vs. As the person walks") 

   
   
3. Compile the script by clicking the compile button.
   
   
4. Ensure that the View's Map Units and Distance Units are correct and the same.
5. Make the grid theme the only active theme in the View.
6. Create and only select one polyline graphic at a time.
7. Make the script window active.
8. Run the script by clicking the run button.