obstruction = false
            --Three spatial coordinate components of a UnitSet2 unit
            y2 = unitset2posits[n].y + altoffset2
            x2 = unitset2posits[n].x
            z2 = unitset2posits[n].z

            m = 1
            
            t = 0
            --check checks of ponits between the UnitSet1 unit and the
            --UnitSet2 unit.  If at any point there is a terrain obstruction, then
            --obstruction (initialized to false) will be set to true.
            --print('here2')
            if (radius and (((x2 - x1)^2 + (z2 - z1)^2)^0.5 > radius)) then
                obstruction = true  --not techinically an "obstruction", but logically the same
                --print('out of range')
            else
                --print('here3')
                while (t <= 1) do
            
                    t =  m/checks
                            
                    yline = y1 + (y2 - y1)*t    
                    xline = x1 + (x2 - x1)*t        
                    zline = z1 + (z2 - z1)*t
                
                    --now do a terrain height @ position check
                    xpcheck = xline
                    zpcheck = zline
                
                    pcheck = { x = xpcheck, y = zpcheck }
                
                    yland = land.getHeight(pcheck)
                
                    --If the land altitude is EVER greater than the
                    --line altitude, set obstruction to true
                    
                    if yland > yline then
                        --print('here- obstruction')
                        obstruction = true
                        break
                    end
                    m = m + 1
                end --while (t <= 1) do
            end