Infrastructure Modeling DevBlog

Setting the center of map programmatically

By Daniel Du

Q:

I want to zoom a map to screen center without changing the scale, how can I do it?

A:

In Map 3D, if you have connected to FDO data sources and added them to map, you can call AcMapMap.ZoomToExtent() to set the new extent of map. It accepts a parameter of MgEnvelope type. If you do not have any FDO data source, you have to use AutoCAD APIs.

Here is the code snippet:

[CommandMethod("ZoomCenter")]

public void ZoomCenter()

{

 

  Document doc = Application.DocumentManager.MdiActiveDocument;

  Database db = doc.Database;

  Editor ed = doc.Editor;

 

  Point3d centerPt;

  PromptPointOptions ppo = new PromptPointOptions(

                "Click on map to zoom center:");

  PromptPointResult ppr = ed.GetPoint(ppo);

  if (ppr.Status == PromptStatus.OK)

  {

    centerPt = ppr.Value;

 

    AcMapMap map = AcMapMap.GetCurrentMap();

    MgEnvelope mapExtent = map.GetMapExtent();

 

    //There are some FDO feature source connected

    if (!mapExtent.IsNull())

    {

      double centerX = mapExtent.LowerLeftCoordinate.X

                                    + mapExtent.Width / 2;

      double centerY = mapExtent.LowerLeftCoordinate.Y

                                    + mapExtent.Height / 2;

 

      ed.WriteMessage("center:" + centerX.ToString() + ","

                                + centerY.ToString() + "\n");

 

      MgEnvelope newExtent = new MgEnvelope(

          centerPt.X - mapExtent.Width  / 2,

          centerPt.Y - mapExtent.Height / 2,

          centerPt.X + mapExtent.Width  / 2,

          centerPt.Y + mapExtent.Height / 2);

 

      map.ZoomToExtent(newExtent);

    }

    else

    {

      //no FDO data source, use AutoCAD API

 

      using (Transaction Tx = db.TransactionManager.StartTransaction())

      {

        ed.UpdateTiledViewportsInDatabase();

 

        ViewportTableRecord viewportTableRec = Tx.GetObject(

                ed.ActiveViewportId, OpenMode.ForWrite)

                as ViewportTableRecord;

 

        viewportTableRec.CenterPoint = new Point2d(centerPt.X, centerPt.Y);

 

        ed.UpdateTiledViewportsFromDatabase();

 

        Tx.Commit();

      }

 

    }

 

 

  }

 

}

Hope this helps.

Computing distance in Map 3D using .net API

By Daniel Du

Q:

I'd like to know how to compute the distance of two points using map 3D .net API

A:

Here is the sample code to do the same:

[CommandMethod("ComputeDistance")]

public void ComputeDistance()

{

  //I am using LL84 coordinate system for this sample

  //As an example, this is longtitue/Latitue of two points

 

  double x1 = -87.7104750022991;

  double y1 = 43.7017449116101;

  double x2 = -87.703061972587;

  double y2 = 43.7016702994388;

 

  Editor ed = Application.DocumentManager.MdiActiveDocument.Editor;

 

  //Get coordinate system of current map

  AcMapMap currentMap = AcMapMap.GetCurrentMap();

  string srsWkt = currentMap.GetMapSRS();

  //ed.WriteMessage("srs = " + srsWkt + "\n");

  MgCoordinateSystemFactory coordSysFactory = new MgCoordinateSystemFactory();

  MgCoordinateSystem coordSys = coordSysFactory.Create(srsWkt);

 

  //compute gread circle distance

  double distance = coordSys.MeasureGreatCircleDistance(x1, y1, x2, y2);

  distance = coordSys.ConvertCoordinateSystemUnitsToMeters(distance);

  ed.WriteMessage("gread circle dist = " + distance.ToString() + "\n");

 

  //compute Euclidean distance

  distance = coordSys.MeasureEuclideanDistance(x1, y1, x2, y2);

  distance = coordSys.ConvertCoordinateSystemUnitsToMeters(distance);

  ed.WriteMessage("Euclidean distance = " + distance.ToString() + "\n");

 

 

  //Another method, compute the distance from Newyork to Boston

  MgCoordinateSystemMeasure coordSysMeasure = coordSys.GetMeasure();

  double dist = coordSysMeasure.GetDistance(-74.806394, 40.714169, -71.061342, 42.355892);

  dist = coordSys.ConvertCoordinateSystemUnitsToMeters(dist);

  ed.WriteMessage("distance from Newyork to Boston is " + dist.ToString() + " meters\n");

 

}

Hope this helps.

Mimic OnCheckIn Event in Map 3D

By Daniel Du

Have you ever run into such scenario that value of one field is computed from other fields? For example we can calculate the total land price from land price per unit and area. Most RDBMS can do this with stored procedure or similar, but for file based data source like SDF or SHP file, we have to do this ourselves by code. A good chance to do the calculation is when the modification on features are checked in, it would be better if Map 3D API provides an event like OnCheckIn, unfortunately, there is no such events in Geospatial Platform API.

But it can be done by a combination of serials events, they are FeatureInserted, FeatureUpdated, and FeatureDeleted of AcMapFeatureService.

Following code snippet domos how to use FeatureUpdated event, you can implement the other two to mimic OnCheckIn event is Map 3D. I blogged this topic a few years ago on my personal blog, if you prefer to read Chinese, please go to this link.

// (C) Copyright 2012 by Autodesk

//

using System;

using Autodesk.AutoCAD.Runtime;

using Autodesk.AutoCAD.ApplicationServices;

using Autodesk.AutoCAD.DatabaseServices;

using Autodesk.AutoCAD.Geometry;

using Autodesk.AutoCAD.EditorInput;

using Autodesk.Gis.Map.Platform;

using OSGeo.MapGuide;

 

// This line is not mandatory, but improves loading performances

[assembly: CommandClass(typeof(MapOnCheckIn.MyCommands))]

 

namespace MapOnCheckIn

{

 

  // This class is instantiated by AutoCAD for each document when

  // a command is called by the user the first time in the context

  // of a given document. In other words, non static data in this class

  // is implicitly per-document!

  public class MyCommands

  {

 

    Editor ed = Application.DocumentManager.MdiActiveDocument.Editor;

 

    //Following code sample demos how to mimic the OnCheckIn event

    //when features are updated using fs.FeatureUpdated,

    //You will need to implement FeatureDeleted  and FeatureInserted yourself

 

    [CommandMethod("AddFsEvents")]

    public void AddFeatureServicesEvents()

    {

      AcMapFeatureService fs = AcMapServiceFactory.GetService(

          MgServiceType.FeatureService) as AcMapFeatureService;

      fs.FeatureUpdated += new FeatureUpdatedHandler(fs_FeatureUpdated);

 

      AcMapMap currentMap = AcMapMap.GetCurrentMap();

      currentMap.FeatureInstanceModified +=

        new FeatureInstanceModifiedHandler(currentMap_FeatureInstanceModified);

 

    }

 

    // Triggered at once when the feature is updated, even it is not checked,

    // This is not what we want.

    void currentMap_FeatureInstanceModified(object sender,

                  FeatureInstanceModifiedEventArgs args)

    {

      ed.WriteMessage("FeatureInstanceModified fired!\n");

    }

 

    //Triggered  when the feature is updated and checked in,

    //This is the one we are looking for, it only triggered when checked in

    //We can get the feature which is being checked in by Args.GetFeature()

    //if more than one feature are updated, it will be fired more times

    //so you can catch this even to handle each of them.

 

    void fs_FeatureUpdated(object sender, AcMapFeatureEventArgs args)

    {

      ed.WriteMessage("FeatureUpdated fired! \n");

      ed.WriteMessage("--------------------------------------\n");

      ed.WriteMessage("PropertyName \t Value \n");

      MgPropertyCollection props = args.GetFeature().GetProperties();

      int propCount = props.Count;

      for (int i = 0; i < propCount; i++)

      {

        string propName = props[i].Name;

        string valueString;

        switch (props[i].GetPropertyType())

        {

          case MgPropertyType.Int32:

            valueString = (props[i] as MgInt32Property).GetValue().ToString();

            break;

 

          case MgPropertyType.String:

            valueString = (props[i] as MgStringProperty).GetValue().ToString();

            break;

          default:

            valueString = "<***>";

            break;

        }

 

        ed.WriteMessage(propName + "\t" + valueString + "\n");

 

      }

      ed.WriteMessage("------------------------------------\n");

 

 

    }

  }

 

}

 

Hope this helps.

Run MapClean Profile Programmatically

By Daniel Du

I am asked about this question: I know how to run MapClean in Map 3D UI, and create/load profile to run the mapclean process repeatedly. but is it possible to run MapClean programmatically? The answer is yes, we can create a custom application to run MapClean programmatically. Here is the code snippet, please note that we need add reference to ManagedMapApi.dll, which can be found in Map 3D installation folder.

 

[CommandMethod("clean")]

public void DrawingCleanUp()

{

 

  Autodesk.Gis.Map.Topology.Variable cadAction

    = new Autodesk.Gis.Map.Topology.Variable();

  //Load a dpf script file, it can be generated by Map 3D UI

  cadAction.LoadProfile(@"C:\Work\mapcleandemo\myclean.dpf");

 

  //The instance of this class should be released by explicitly

  //calling Dispose() in order to avoid memory leak.

  //See also 'using' keyword in C# and VB.Net.

  using (Autodesk.Gis.Map.Topology.TopologyClean cadCleanobj

      = new Autodesk.Gis.Map.Topology.TopologyClean())

  {

    //Open a file first to avoid MapTopologyException

    cadCleanobj.Init(cadAction, null);

 

    cadCleanobj.Start();

    cadCleanobj.GroupNext();

 

    while (!cadCleanobj.Completed)

    {

      cadCleanobj.GroupFix();

      cadCleanobj.GroupNext();

    }

    //Commit the changes

    cadCleanobj.End();

  }

 

}

 

Hope this helps!

Change the name of the current map in the Display Manager

By Daniel Du

If you are trying to change the name of current map in display manager from “Default”? Here is the solution. To change the map name in the Display Manager, you need to get the map Id and use this map ID to get the map object, then assign a new value to the "Name" property of the map object. You will be using the Display Manager API for this.

// (C) Copyright 2012 by Autodesk

//

using System;

using Autodesk.AutoCAD.Runtime;

using Autodesk.AutoCAD.ApplicationServices;

using Autodesk.AutoCAD.DatabaseServices;

using Autodesk.AutoCAD.Geometry;

using Autodesk.AutoCAD.EditorInput;

using Autodesk.Gis.Map;

using Autodesk.Gis.Map.Project;

using Autodesk.Gis.Map.DisplayManagement;

 

// This line is not mandatory, but improves loading performances

[assembly: CommandClass(typeof(ChangeMapNameInDM.MyCommands))]

 

namespace ChangeMapNameInDM

{

 

  // This class is instantiated by AutoCAD for each document when

  // a command is called by the user the first time in the context

  // of a given document. In other words, non static data in this class

  // is implicitly per-document!

  public class MyCommands

  {

 

    Editor ed = Application.DocumentManager.MdiActiveDocument.Editor;

    MapApplication app = HostMapApplicationServices.Application;

 

    [Autodesk.AutoCAD.Runtime.CommandMethodAttribute("CHGMAPNAME")]

    public void ChangeMapName()

    {

      try

      {

        string mapName = null;

        PromptResult stringPromptResult = null;

        bool succeeded = false;

        stringPromptResult = ed.GetString("\nEnter the new Map name:");

 

        mapName = stringPromptResult.StringResult.Trim();

        if (stringPromptResult.Status == PromptStatus.OK

                          && mapName.Length > 0)

        {

          succeeded = changeMapName(mapName);

        }

        else

        {

          ed.WriteMessage("\nERROR: Invalid Map name");

        }

 

        if (!succeeded)

        {

          ed.WriteMessage("\nERROR: Name change failure");

        }

      }

      catch (System.Exception err)

      {

        ed.WriteMessage(err.Message);

      }

    }

 

 

    private bool FindCurrentMapId(ref ObjectId currentMapId)

    {

      bool isFound = false;

      // Get the project associated with the current AutoCAD document

      ProjectModel project = null;

      Autodesk.AutoCAD.DatabaseServices.TransactionManager TM

        = app.ActiveProject.Database.TransactionManager;

      project = app.ActiveProject;

 

      try

      {

        using (Transaction trans = TM.StartTransaction())

        {

          ObjectId managerId = DisplayManager.Create(project)

                              .MapManagerId(project, true);

          MapManager manager = trans.GetObject(managerId, OpenMode.ForRead)

                              as MapManager;

          if (null != manager)

          {

            currentMapId = manager.CurrentMapId;

            isFound = true;

          }

          trans.Commit();

        }

      }

      catch (Autodesk.AutoCAD.Runtime.Exception)

      {

        ed.WriteMessage("\nUnable to get the current Map's Object ID.");

      }

 

      return isFound;

    }

 

    public bool changeMapName(string name)

    {

      // Get the Object Id for the current Map

      ObjectId currentMapId = new ObjectId();

      string message = "";

      Autodesk.AutoCAD.DatabaseServices.TransactionManager TM

        = app.ActiveProject.Database.TransactionManager;

 

      if (!FindCurrentMapId(ref currentMapId))

      {

        return false;

      }

 

 

      try

      {

        using (Transaction trans = TM.StartTransaction())

        {

          Map currentMap = (Map)trans.GetObject(currentMapId, OpenMode.ForWrite);

          // Change the name

          currentMap.Name = name;

 

          trans.Commit();

        }

 

      }

      catch (Autodesk.AutoCAD.Runtime.Exception ex)

      {

        message = string.Format("\nUnable to change name, msg:{0}",

                                ex.Message);

        ed.WriteMessage(message);

      }

 

      return true;

    }

  }

}

 

Please note that this method does not work for Map 3D 2013, it throws an exception with error message “eCreateInvalidName”, a change request have been logged, I will update this blog if there are some new information about this.

Using FDO API to select Features from FDO Data Source

By Partha Sarkar

Following code snippet demonstrates how to establish a connection using a specific FDO provider (in this case it's SDF Provider) and then use FDO.Filter to query a set of FDO Features based on a specific query condition.

 

OSGeo.FDO.IConnectionManager connManager = FeatureAccessManager.GetConnectionManager();

IConnection conn = connManager.CreateConnection("OSGeo.SDF.3.7");

conn.ConnectionInfo.ConnectionProperties.SetProperty("ReadOnly", false.ToString());           

string fileName = @"C:\2013_Release\Map3D_2013\2013_API_Samples\Platform_API\Data\SDF\Roads.sdf";

conn.ConnectionInfo.ConnectionProperties.SetProperty("File", fileName);

conn.Open();

 

// Create the selection command

ISelect selCmd = (ISelect)conn.CreateCommand(CommandType.CommandType_Select);           

Identifier id = new Identifier("Roads");

selCmd.FeatureClassName = id;

 

// Set a Filter to Select road Lengths greater than 6000 meter

OSGeo.FDO.Filter.Filter filter = OSGeo.FDO.Filter.Filter.Parse("LENGTH > 6000");

selCmd.Filter = filter;

IFeatureReader ftrRdr = selCmd.Execute();

ed.WriteMessage("\nStreet name   ---------------  Length \n");

while (ftrRdr.ReadNext())

{

    string streetName =  ftrRdr.GetString("ST_NAME");

    double length = ftrRdr.GetDouble("LENGTH");

    ed.WriteMessage(streetName + "     " + length + "\n");

}

conn.Close();

 

Hope this is useful to you!

 

Remove the Discrepancy Between ArcView/ArcGIS and Map 3D When Deleting Features

By Daniel Du

In last post, I introduced how to delete selected features in Map 3D using APIs, some users argue that there is a discrepancy for SHP files when examining the file in ArcGIS, the deleted features in Map 3D still appear in ArcGIS when FDO connection in Map 3D is still open.

To better understand this problem, let’s examine the modification date of files firstly. Following screen-shot is the shp files before deleting in Map 3D:

And following is another screen-shot when the features are deleted in Map 3D using the custom command we introduced in last post.

You may notice that only the *.dbf file is modified, while *.shp does not.

Is this a bug of Map 3D? First, here are some background regarding SHP files and the FDO SHP provider:

· A  DBF record holds the attributes + a Delete flag. When a geometry is deleted this flag is set. The geometry is still in the SHP file but marked for deletion in DBF. If you are interested in the DBF specification, please refer to this doc.

· The weird aspect of this flag is that while it is part of the ESRI SHP specification it is ignored by applications like ArcGIS or TatukGis Viewer.

In the past development team made a significant deal of effort to address this issue. They ended up by compressing (i.e. effectively deleting the records) the SHP files (.dbx, .shx, .shp) when the last connection is closed. This is because, obviously, it is non-performant to compress the files for every single deleted feature (these files can be extremely large). o it is as designed, shp file is only compressed when the connection is closed.

But for some reason, customer may want to sync the changes between Map 3D and ArcGIS more frequently, is there any a way to compress the shp explicitly? Unfortunately, there is no such APIs in Map 3D, but since it will be compressed when the connection is closed, how about to close the connection programmatically? Yes, that is the solution.

If you examine the BuidMap sample in Map 3D ObjectARX SDK, you will understand that the process of creating a connection to FDO datasource and adding layer to map is actually a process of create feature source and layer definition using resource service. So we of cause can disconnect by deleting these resources.

Here is the code snippet:

 

[CommandMethod("CloseConnection")]

public void CloseConnectionForLayer()

{

RemoveLayer("Layer1");

}

 

public void RemoveLayer(string layerName)

{

Document doc = Application.DocumentManager.MdiActiveDocument;

Editor ed = doc.Editor;

Database db = doc.Database;

 

AcMapMap map = AcMapMap.GetCurrentMap();

 

// remove the layer

var layers = map.GetLayers();

if (!layers.Contains(layerName))

{

  ed.WriteMessage("\nLayer does not exist: " + layerName);

  return;

}

 

MgLayerBase layer = layers.GetItem(layerName);

layers.Remove(layer);

 

// remove the layer resource

MgResourceIdentifier identifier = layer.LayerDefinition;

MgResourceService resourceService

  = AcMapServiceFactory.GetService(MgServiceType.ResourceService)

  as MgResourceService;

 

if (resourceService.ResourceExists(identifier))

  resourceService.DeleteResource(identifier);

 

// remove the feature source

identifier = new MgResourceIdentifier(layer.FeatureSourceId);

if (resourceService.ResourceExists(identifier))

  resourceService.DeleteResource(identifier);

 

 

}

 

By this way, the SHP layer is removed from map and FDO connection is closed, let’s examine the modification data again, the SHP files (.dbx, .shx, .shp) are modified. The result will be synced with ArcGIS now.

If you need to keep working the SHP file in Map 3D, you need to re-create the connection using the way introduced in BuildMap Sample. As you can imagine, this workaround may cause performance issue if you do that very frequently, so please apply it only when necessary.

Hope this helps.

Deleting Selected Features in Map 3D using APIs

By Daniel Du

Feature editing is probably the most common operation in Map 3D. In this blog I will show you how to delete selected features in Map 3D. Let's dive into the code directly, as the code is pretty self-explanatory. Just please note that you need to commit the changes using aclayer.SaveFeatureChanges(opt):

Here is the code snippet:

    [CommandMethod("DeleteSelectedFeatures", CommandFlags.UsePickSet

          | CommandFlags.Modal | CommandFlags.Redraw)]

    public void DeleteSelectedFeatures()

    {

      Editor ed = Autodesk.AutoCAD.ApplicationServices

          .Application.DocumentManager.MdiActiveDocument.Editor;

      MgFeatureService _featureService = AcMapServiceFactory

        .GetService(MgServiceType.FeatureService) as MgFeatureService;

      PromptSelectionResult res = ed.SelectImplied();

 

      if (PromptStatus.OK == res.Status)

      {

        // Convert the SelectionSet to MgSelectionBase

        // using AcMapFeatureEntityService.

 

        Debug.Assert(res.Value != null);

        ObjectId entityID = res.Value[0].ObjectId;

        int entitytype = AcMapFeatureEntityService.GetEntityType(entityID);

        if (entitytype == EntityType.BulkEntity)

        {

          MgSelectionBase curSelection = AcMapFeatureEntityService

                                    .GetSelection(res.Value);

 

          foreach (MgLayerBase layer in curSelection.GetLayers())

          {

            string filter = curSelection

                  .GenerateFilter(layer, layer.FeatureClassName);

 

            if (filter != "")

            {

              MgFeatureCommandCollection featCommands =

                new MgFeatureCommandCollection();

 

              string strclassName = layer.FeatureClassName;

              MgDeleteFeatures delFeat =

                new MgDeleteFeatures(strclassName, filter);

              featCommands.Add(delFeat);

              try

              {

                AcMapLayer aclayer = layer as AcMapLayer;

                MgPropertyCollection pProps = aclayer

                  .UpdateFeatures(featCommands);

 

                // save and update the layer, commite the changes

 

                MgFeatureQueryOptions opt = new MgFeatureQueryOptions();

 

                // build the filter string, this is required for

                // data source such as Sql Server/Oracle...

 

                String commitFilter = "";

                if (aclayer.IsCached()

                    && EditMode.EditSet == aclayer.EditMode)

                {

                  commitFilter = ClassSystemProperties.FeatureStatus

                    + " = "

                    + ClassSystemProperties.FeatureStatusDeleted;

                }

 

                opt.SetFilter(commitFilter);

 

                //This is a must

 

                aclayer.SaveFeatureChanges(opt);

                aclayer.ForceRefresh();

              }

              catch (Autodesk.AutoCAD.Runtime.Exception ex)

              {

                ed.WriteMessage(ex.Message);

              }

            }

          }

 

          //remove the highlight

 

          AcMapFeatureEntityService.UnhighlightFeatures(curSelection);

        }

      }

    }

Here is the screen-shot of running this custom command, user should select some features to be deleted firstly:

Once the command is executed, the selected feature is deleted:

Hope this helps!

Delete Map 3D Object Data Table using ActiveX Automation API

By Partha Sarkar

Currently there is no method exposed through Map 3D ActiveX Automation API to delete the Object Data table. We can use the following MAP LISP API functions as a workaround (ade_oddeletetab tabname)

This function deletes the specified table. You can use SendCommand method of document object to invoke this function. The following example shows how to remove a OD Table in Map 3D - 

 

Sub f_deleteOdtable(ps_odTableName As String)

  ThisDrawing.SendCommand ("(ade_oddeletetab """ & ps_odTableName & """) ")

End Sub 

 

Sub f_test()

  Call f_deleteOdtable("test")

  'you must have an object data table by name "test"

End Sub

 

Verify if a FDO feature attribute is 'empty' using Map 3D API

By Partha Sarkar

In the screenshot below, we can see the Name attribute of two features are Empty. In my FDO data set I have hundreds of thousands of features and I would like to find out if any attribute is empty (i.e. there is no Value) for selected features in Map 3D using API.

 

 

Here is a relevant C# code snippet in Map 3D which will check if the “Name” attribute of any selected Feature is Empty and if it is Empty, it will show the Feature ID and a message that “Name Attribute is Empty “ at the Map 3D command Line.

 

AcMapMap currentMap = AcMapMap.GetCurrentMap();

MgLayerCollection layers = currentMap.GetLayers();

 

PromptSelectionResult selResult = ed.GetSelection();

if (selResult.Status == PromptStatus.OK)

{

  SelectionSet selSet = selResult.Value;

  MgSelectionBase selectionBase = AcMapFeatureEntityService.GetSelection(selSet);

 

  //Ensure user selected a feature

  MgLayerBase myLayer = null;

  foreach (MgLayerBase layer in selectionBase.GetLayers())

  {

    if (layer.Name == "API_Poly_Objects")   // change to your own layer name

    {

      myLayer = layer;

      break;

    }

  }

  if (myLayer == null)

  {

    ed.WriteMessage("No Feature is selected from the designated Layer ! ");

    return;

  }

 

  //get the properties

  MgFeatureReader reader = selectionBase.GetSelectedFeatures(myLayer, myLayer.FeatureClassName, false);

  try

  {

    while (reader.ReadNext())

    {

      string featureName = reader.GetString("Name");  // this this just a demo, change this according to your data field

      if (featureName == "")

      {

        Int32 FeatureID = reader.GetInt32("ID");  // this this just a demo, change this according to your data field

        ed.WriteMessage("\n Feature ID :" + FeatureID.ToString() + " Name Attribute is Empty ");

      }

    }

  }

  finally

  {

    reader.Close();

  }

}

 

Hope this is useful to you!