Development of Linear Measure Tool using Application Framework Venkatesh Merwade

Overview Necessity for Linear Referencing Application Framework About Linear Measure Tool PolylineM LengthDown Application of LMT Conclusions, Acknowledgements, Questions!

Necessity for Linear Referencing GIS often represents spatial information with two dimensional coordinate systems. Location of river gauging station x,y coordinates - (992506,301256) Linear measure - HydroCode = 30021, m=165 Add route events Find distance between two points and so on.

Application Framework What is it?? It’s an ArcMap extenstion Designed to access ArcMap layers for input and create new output layers (right now used only for input).

Why AppFramework? Here is how it all works AppFramework Get hold of MxDocument Get hold of Map Get hold of FeatureLayer Get hold of FeatureClass Get hold of required Field in FeatureClass Do Something, have fun! Display results AppFramework

Sub LengthDown() Dim pMxDoc As IMxDocument Dim pMap As IMap Set pMxDoc = ThisDocument Set pMap = pMxDoc.FocusMap Dim pFLayer As IFeatureLayer Dim pFeature As IFeature Set pFLayer = pMap.Layer(0) Dim pFC As IFeatureClass Set pFC = pFLayer.FeatureClass Dim pTable As ITable Set pTable = pFC Dim j As Long j = pTable.FindField(“LengthDown") If j = -1 Then MsgBox “Field not found" Exit Sub End If MsgBox “Field Found” End Sub

Linear Measure Tool (LMT) It’s developed in Visual Basic as a DLL. Uses AppFramework for input. Register in ArcMap to use it. Toolbar with some cool options for Linear Referencing. Works only with PolylineM layer and uses LengthDown for multiple features option.

Why LMT is so cool! It has some cool options! Assign Ms Read Ms Finds out distance between two points Deals with both Individual and Multiple Features Changes the MDomain on fly if necessary It flashes but never crashes (sometimes gives error message, but that’s not LMT, it’s user!)

Application of LMT

Conclusions Using Visual Basic, I can do some cool stuff too. It’s very easy. Here we are dealing with only one type of Layer (PolylineM). AppFramework is more useful when dealing with different types of layers and fields.

Acknowledgements Dr. Maidment Tim Whiteaker CRWR crew