[mapguide-users] help

Kenneth Skovhede, GEOGRAF A/S ks at geograf.dk
Wed May 20 03:42:25 EDT 2009


UNIT is the coordinate system unit, eg. degrees, meters or inches.

If the layers and map have the correct coordinate systems assigned,
MapGuide will automatically convert the data to display correctly,
so you get the correct map.

You do not have to work with the projection string manually.
Beware of trying to calculate coordinates manually based on the UNIT, 
because
projections are not always compatible just because the use the same UNIT.
Instead, use the MgCoordinateSystem classes to convert points from one 
projection to another.

Regards, Kenneth Skovhede, GEOGRAF A/S



saloua wakrim skrev:
> but please if you know what that UNIT means in coordinates System say 
> it me:
>  
>
> <
>
> CoordinateSystem>GEOGCS["WGS84 Lat/Long's, Degrees, -180 ==> 
> +180",DATUM["D_WGS_1984",SPHEROID["World_Geodetic_System_of_1984",6378137,298.257222932867]],PRIMEM["Greenwich",0],*_UNIT_*["Degree",0.017453292519943295]]</CoordinateSystem> 
> cause i want draw polygone representing view of cam (dome) and it must 
> be proportional to the real view of cam, and my layer must be added to 
> map with another layer wich contains cams so i must know wich units is 
> used on map(m, km, cm) or what? that what i do that i convert (m) to 
> unit by this code:
>  
>
> MgCoordinateSystemFactory
>
> csFactory = new MgCoordinateSystemFactory(); MgCoordinateSystem srs = 
> csFactory.Create(map.GetMapSRS()); MgCoordinateSystemMeasure mesure = 
> new MgCoordinateSystemMeasure(srs);
>
> distanceunits = pointa.Distance(pointb, mesure);
>
> Response.Write(
>
> "distance entre les deux points du calque en unit‚: 
> "+distanceunits.ToString());
>
> distancemeters = srs.ConvertCoordinateSystemUnitsToMeters(distanceunits);
>
> but i don't know if this layer (wich contains polygone) will be 
> compatible with another layer or not? if you don't understand me say 
> it me please. thanks or advance, i ask you cause i remark that you 
> master more than onother mapguide developpers mapguide, thanks on 
> advance.  
>
> 2009/5/19 Kenneth Skovhede, GEOGRAF A/S <ks at geograf.dk 
> <mailto:ks at geograf.dk>>
>
>     There is an example for MgCreateSdfParams() in the
>     "buffer.(php|aspx|jsp)" file in the folder
>     C:\program
>     files\MapGuideOpenSource2.0\WebServerExtensions\www\mapviewer(php|net|java)
>
>     It also shows how to set the coordinate system.
>     If your data has the correct projection, MapGuide will convert it
>     to fit the map projection.
>     If that does not work, you have to manually convert the items,
>     which is not a trivial procedure.
>
>     Regards, Kenneth Skovhede, GEOGRAF A/S
>         
>
>
>
>     saloua wakrim skrev:
>>     hi! did you know lease how MgCreateSdfParams() works and what
>>     attributes i must give it cause ii think that the prob i have is
>>     coordinates i use for inserting polygone or line or point wich
>>     are not compatibl with map cordinates 
>>
>>     2009/5/11, Kenneth Skovhede, GEOGRAF A/S <ks at geograf.dk
>>     <mailto:ks at geograf.dk>>:
>>
>>         Yes, that looks right.
>>
>>         You must also refresh the map (refresh/pan/zoom/etc.) in the
>>         browser via javascript.
>>
>>         In addition to my other suggestions, you can also check the
>>         error log for messages.
>>
>>         Regards, Kenneth Skovhede, GEOGRAF A/S
>>             
>>
>>
>>
>>         saloua wakrim skrev:
>>>         hi! please i want know if this code is that what all i must
>>>         do for adding new layer to map and see it in viewer frame or
>>>         i must do some relation with the feature source i create in
>>>         my code?? thanks on advance
>>>          
>>>
>>>         myLayer =
>>>
>>>         New MgLayer(layerDefId, resourceSrvc)
>>>
>>>         myLayer.SetName(myLayerName)
>>>
>>>         myLayer.SetLegendLabel(myLayerName)
>>>
>>>         myLayer.SetDisplayInLegend(
>>>
>>>         True)
>>>
>>>         myLayer.SetSelectable(
>>>
>>>         False)
>>>
>>>         map.GetLayers().Insert(0, myLayer)
>>>
>>>         myLayer.ForceRefresh()
>>>
>>>         map.Save(resourceSrvc)
>>>
>>>          
>>>         2009/5/10 Kenneth Skovhede, GEOGRAF A/S <ks at geograf.dk
>>>         <mailto:ks at geograf.dk>>
>>>
>>>             The code looks alright.
>>>             Do you refresh the map afterwards?
>>>             What is in the "insertResults" ?
>>>             (There can be a hidden error, due to a bug in MapGuide)
>>>             Are you sure that the LayerDefinition matches the
>>>             FeatureSource?
>>>             Try to create the FeatureSource and LayerDefinition in
>>>             "Library://" instead,
>>>             so you can examine the layer from Studio/Maestro.
>>>
>>>             Regards, Kenneth Skovhede, GEOGRAF A/S
>>>                 
>>>
>>>
>>>
>>>             saloua wakrim skrev:
>>>>             i try the following code for displaying layer wich
>>>>             contains line in map, so i digitize a line, create
>>>>             temporary feature for this line, create a layer wich
>>>>             contains it and add it to the map. it doesn't give me
>>>>             some error but  i can see the line in the map (i can
>>>>             draw it). Please help me. the code is following:
>>>>              
>>>>              
>>>>
>>>>             String
>>>>
>>>>             dataSource = "Session:" + sessionid1 + "//" +
>>>>             myLayerName + ".FeatureSource"; MgResourceIdentifier
>>>>             dataSourceId = new MgResourceIdentifier(dataSource);
>>>>             MgFeatureService featureSrvc =
>>>>             (MgFeatureService)siteConnection.CreateService(MgServiceType.FeatureService);
>>>>             if (DoesLayerExist(myLayerName, map) == false)
>>>>
>>>>             {
>>>>
>>>>              
>>>>
>>>>             //create Feature Source MgClassDefinition myClassDef =
>>>>             new MgClassDefinition();
>>>>
>>>>             myClassDef.SetName(myLayerName);
>>>>
>>>>             myClassDef.SetDescription(myLayerName +
>>>>
>>>>             " Feature Source");
>>>>
>>>>             myClassDef.SetDefaultGeometryPropertyName(
>>>>
>>>>             "SHPGEOM"); MgDataPropertyDefinition prop = new
>>>>             MgDataPropertyDefinition("KEY");
>>>>
>>>>             prop.SetDataType(
>>>>
>>>>             MgPropertyType.Int32);
>>>>
>>>>             prop.SetAutoGeneration(
>>>>
>>>>             true);
>>>>
>>>>             prop.SetReadOnly(
>>>>
>>>>             true);
>>>>
>>>>             myClassDef.GetIdentityProperties().Add(prop);
>>>>
>>>>             myClassDef.GetProperties().Add(prop);
>>>>
>>>>             prop =
>>>>
>>>>             new MgDataPropertyDefinition("ID");
>>>>
>>>>             prop.SetDataType(
>>>>
>>>>             MgPropertyType.Int32);
>>>>
>>>>             myClassDef.GetProperties().Add(prop);
>>>>
>>>>             MgGeometricPropertyDefinition geomProp = new
>>>>             MgGeometricPropertyDefinition("SHPGEOM");
>>>>
>>>>             geomProp.SetGeometryTypes(
>>>>
>>>>             MgFeatureGeometricType.Curve);
>>>>
>>>>             myClassDef.GetProperties().Add(geomProp);
>>>>
>>>>             MgFeatureSchema schema = new
>>>>             MgFeatureSchema(myLayerName + "Schema", myLayerName +
>>>>             "SchemaDesc");
>>>>
>>>>             schema.GetClasses().Add(myClassDef);
>>>>
>>>>             MgCreateSdfParams sdfParams = new
>>>>             MgCreateSdfParams("MGA-56 (GDA94 / MGA zone 56)",
>>>>             map.GetMapSRS(), schema);
>>>>
>>>>             featureSrvc.CreateFeatureSource(dataSourceId, sdfParams);
>>>>
>>>>              
>>>>
>>>>              
>>>>
>>>>             //create layer //String layerDef = "Session:" +
>>>>             sessionid1 + "//" + myLayerName + ".LayerDefinition";
>>>>             MgResourceIdentifier layerDefId = new
>>>>             MgResourceIdentifier("Library://essaicalque/Redline.LayerDefinition");
>>>>
>>>>
>>>>              
>>>>
>>>>              
>>>>
>>>>             MgByteSource content = new MgByteSource(@"C:\Program
>>>>             Files\MapGuideOpenSource\WebServerExtensions\www\essaiselect2\Layerdef.xml");
>>>>
>>>>
>>>>             resourceSrvc.SetResource(layerDefId, content.GetReader(),
>>>>
>>>>             null); //code enlev‚ d'ici: ajouter layer resource … la
>>>>             carte //il faut ajouter l'autre code: add layer
>>>>             resource to map //DOMDocument domdoc = new
>>>>             DOMdocument(); MgLayer
>>>>             result=add_layer_resource_to_map(layerDefId,resourceSrvc,myLayerName,myLayerName,map);
>>>>
>>>>
>>>>             }
>>>>
>>>>             MgInsertFeatures insertFeatures = new
>>>>             MgInsertFeatures(myLayerName, makeLine("1", x0, y0, x1,
>>>>             y1)); MgFeatureCommandCollection commands = new
>>>>             MgFeatureCommandCollection();
>>>>
>>>>             commands.Add(insertFeatures);
>>>>
>>>>             int commandIndex = commands.IndexOf(insertFeatures);
>>>>             MgPropertyCollection insertResults;
>>>>
>>>>             insertResults =
>>>>             featureSrvc.UpdateFeatures(dataSourceId, commands,
>>>>
>>>>             false); MgLayer myLayer1 =
>>>>             map.GetLayers().GetItem(myLayerName) as MgLayer;
>>>>
>>>>             myLayer1.ForceRefresh();
>>>>
>>>>              
>>>>
>>>>             //commands.Add(new
>>>>             MgInsertFeatures(myLayerName,makeLine("1", x0, y0, x1,
>>>>             y1)));
>>>>
>>>>              
>>>>
>>>>             map.Save(resourceSrvc);
>>>>
>>>>              
>>>>
>>>>             <
>>>>
>>>>             script runat=server> Boolean result;
>>>>             MgPropertyCollection makeLine(String Name, Double x0,
>>>>             Double y0, Double x1, Double y1)
>>>>
>>>>             {
>>>>
>>>>             MgPropertyCollection PropertyCollection = new
>>>>             MgPropertyCollection(); MgInt32Property nameProperty =
>>>>             new MgInt32Property("ID", 1);
>>>>
>>>>             PropertyCollection.Add(nameProperty);
>>>>
>>>>             MgWktReaderWriter wktReaderWriter = new
>>>>             MgWktReaderWriter(); MgAgfReaderWriter agfReaderWriter
>>>>             = new MgAgfReaderWriter(); MgGeometry geometry =
>>>>             wktReaderWriter.Read("LINESTRING XY (" + x0 + " " + y0
>>>>             + "," + x1 + " " + y1 + ")") as MgLineString;
>>>>             //MgGeometry geometry =
>>>>             wktReaderWriter.Read("LINESTRING(3 4,10 50,20 25)") as
>>>>             MgLineString; MgByteReader geometryByteReader =
>>>>             agfReaderWriter.Write(geometry); MgGeometryProperty
>>>>             geometryProperty = new MgGeometryProperty("SHPGEOM",
>>>>             geometryByteReader);
>>>>
>>>>             PropertyCollection.Add(geometryProperty);
>>>>
>>>>             return PropertyCollection;
>>>>
>>>>             }
>>>>
>>>>             Boolean
>>>>
>>>>             DoesLayerExist(String LayerName, MgMap Map)
>>>>
>>>>             {
>>>>
>>>>             MgLayerCollection layers = Map.GetLayers();
>>>>
>>>>             result = (layers.Contains(myLayerName));
>>>>
>>>>             return result;
>>>>
>>>>             }
>>>>
>>>>             MgLayer add_layer_resource_to_map(MgResourceIdentifier
>>>>             layerresourceid, MgResourceService rs, String
>>>>             layername, String layerlegendlabel, MgMap map)
>>>>
>>>>             {
>>>>
>>>>             MgLayer myLayer = new MgLayer(layerresourceid, rs);
>>>>
>>>>             myLayer.SetName(layername);
>>>>
>>>>             myLayer.SetLegendLabel(layerlegendlabel);
>>>>
>>>>             myLayer.SetDisplayInLegend(
>>>>
>>>>             true);
>>>>
>>>>             myLayer.SetSelectable(
>>>>
>>>>             true);
>>>>
>>>>              
>>>>
>>>>             if (!map.GetLayers().Contains(layername))
>>>>
>>>>             {
>>>>
>>>>             map.GetLayers().Insert(0, myLayer);
>>>>
>>>>             }
>>>>
>>>>             myLayer.SetVisible(
>>>>
>>>>             true);
>>>>
>>>>             myLayer.ForceRefresh();
>>>>
>>>>             map.Save(resourceSrvc);
>>>>
>>>>             return myLayer;
>>>>
>>>>             }
>>>>
>>>>             </
>>>>
>>>>             script>
>>>>
>>>>              
>>>>
>>>>              
>>>>
>>>>              
>>>>
>>>>             ------------------------------------------------------------------------
>>>>
>>>>             _______________________________________________
>>>>             mapguide-users mailing list
>>>>             mapguide-users at lists.osgeo.org <mailto:mapguide-users at lists.osgeo.org>
>>>>             http://lists.osgeo.org/mailman/listinfo/mapguide-users
>>>>               
>>>
>>>             _______________________________________________
>>>             mapguide-users mailing list
>>>             mapguide-users at lists.osgeo.org
>>>             <mailto:mapguide-users at lists.osgeo.org>
>>>             http://lists.osgeo.org/mailman/listinfo/mapguide-users
>>>
>>>
>>>         ------------------------------------------------------------------------
>>>
>>>         _______________________________________________
>>>         mapguide-users mailing list
>>>         mapguide-users at lists.osgeo.org <mailto:mapguide-users at lists.osgeo.org>
>>>         http://lists.osgeo.org/mailman/listinfo/mapguide-users
>>>           
>>
>>         _______________________________________________
>>         mapguide-users mailing list
>>         mapguide-users at lists.osgeo.org
>>         <mailto:mapguide-users at lists.osgeo.org>
>>         http://lists.osgeo.org/mailman/listinfo/mapguide-users
>>
>>
>>     ------------------------------------------------------------------------
>>
>>     _______________________________________________
>>     mapguide-users mailing list
>>     mapguide-users at lists.osgeo.org <mailto:mapguide-users at lists.osgeo.org>
>>     http://lists.osgeo.org/mailman/listinfo/mapguide-users
>>       
>
>     _______________________________________________
>     mapguide-users mailing list
>     mapguide-users at lists.osgeo.org <mailto:mapguide-users at lists.osgeo.org>
>     http://lists.osgeo.org/mailman/listinfo/mapguide-users
>
>
> ------------------------------------------------------------------------
>
> _______________________________________________
> mapguide-users mailing list
> mapguide-users at lists.osgeo.org
> http://lists.osgeo.org/mailman/listinfo/mapguide-users
>   
-------------- next part --------------
An HTML attachment was scrubbed...
URL: http://lists.osgeo.org/pipermail/mapguide-users/attachments/20090520/a42b8876/attachment.html


More information about the mapguide-users mailing list