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How to save a Layer to a Projection?

#1

  In 2.x, there is a convenient way to save a Layer to a projection to avoid having to do projection on the fly. The layer has the function SaveToProjection.


Dim Layer As New Layer("...\MyLayer.shp")

Dim GeoToUTM17N As New GeodeticToUTM17N()


Layer.SaveToProjection("UTM17N", GeoToUTM17N , True)


 


    I could not find a such a simple API in 3.x. What would be the way to accomplish that task in 3.x? Are you planning on offering a simple API for that in the near future?


Thank you.


 


 


 



#2

Adolfo, 
  
 Thanks for reminding. I have writen it down and we will discuss it. I believe we will add a similar API in the near future. 
  
 Now you can accomplish this with the following code. 
  
 
            string sourceShapeFile = @"C:\temp\Countries02.shp";
            string targetShapeFile = @"C:\temp\Countries02Test.shp";
 
            ShapeFileFeatureLayer worldLayer = new ShapeFileFeatureLayer(sourceShapeFile);
            worldLayer.ZoomLevelSet.ZoomLevel01.DefaultAreaStyle = AreaStyles.Country1;
            worldLayer.ZoomLevelSet.ZoomLevel01.ApplyUntilZoomLevel = ApplyUntilZoomLevel.Level20;
 
            worldLayer.Open();
            Collection<Feature> allFeatures = worldLayer.QueryTools.GetAllFeatures(ReturningColumnsType.AllColumns);
            worldLayer.Close();
 
            ShapeFileFeatureSource.CloneShapeFileStructure(sourceShapeFile, targetShapeFile);
            ShapeFileFeatureSource targetFeatureSource = new ShapeFileFeatureSource(targetShapeFile, ShapeFileReadWriteMode.ReadWrite);
            targetFeatureSource.Open();
            proj4Projection.Open();
            targetFeatureSource.BeginTransaction();
            foreach (Feature feature in allFeatures)
            {
                Feature projectedFeature = proj4Projection.ConvertToExternalProjection(feature);
                targetFeatureSource.AddFeature(projectedFeature);
            }
            TransactionResult result = targetFeatureSource.CommitTransaction();
            proj4Projection.Close();
            targetFeatureSource.Close();
 
  
 Thanks, 
  
 Ben

#3

Thank you, Ben. I used your code and I succesfully save a shapefile to UTM from an original shapefile in StatePlane. On my machine, on a 23 Meg shapefile, it took about 35 seconds so I guess this is decent performance.


 



#4

Great! We are working on this and the API (static ShapeFileFeatureSource.SaveToProjection) will be available in the upcoming version. Keep letting us know your great ideas, Adolfo. :) 
  
 Ben.