AutoCAD Map 3D 2009 Geospatial Platform … Up Visual Studio To use the Geospatial Platform API, follow the instructions in the AutoCAD Map 3D ObjectARX .NET Developer’s Guide. Add

Overview

Topicsinthissection

IntroductionRelationshiptoMapGuideGeospatialPlatformAPIDocumentationSettingUpVisualStudioSampleApplications

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Introduction

TheAutoCADMap3D2009GeospatialPlatformAPIisusedformanaginggeospatialdatainamap.ItsharesmanyclassesandmethodswithAutodeskMapGuide®EnterpriseandMapGuideOpenSource,soapplicationswrittenforoneproductcanworkinanotherwithminimalmodification.

TheGeospatialPlatformAPIisnotthesameastheAutoCADMap3DObjectARX.NETAPI.FordetailsaboutthisAPIseetheObjectARX.NETDeveloper’sGuideandtheObjectARX.NETAPIReference.


RelationshiptoMapGuide

ManypartsoftheGeospatialPlatformAPIaresharedbetweenAutoCADMap3DandMapGuideWebServerExtensions.Therearedifferencesintheproducts,though,thataffecthowtheAPIisused.

TheMapGuideAPIisdesignedtobeusedinawebserverenvironment,andisavailableinPHP,Java,and.NET.AutoCADMap3Disdesignedtobeusedinadesktopenvironmentandexposesonlya.NETAPI.

AutoCADMap3DstoressomeresourceinformationdirectlyintheDWGfile,whileMapGuideusesanexternalrepository.ThisisexplainedinmoredetailinResources.TheMapGuiderepositoryisstructuredlikeafilesystem,withahierarchyoffolders.Toensureasmuchconsistencybetweentheproductsaspossible,AutoCADMap3Dusesasimilarstructureforitsinternalrepository.

SomemethodsintheGeospatialPlatformAPIarenotvalidinAutoCADMap3D,andwillthrowanexceptionifcalled.GenerallythesewillbemethodsthatdonothavecorrespondingfunctionalityintheAutoCADMap3Denvironment.Forexample,AutoCADMap3Ddoesnothavetheconceptofpermissionsonresourcessoanymethodsdealingwithpermissionsareinvalid.TheseareidentifiedintheAPIReference.

AllmapdatainaMapGuideapplicationiswrittenandreadthroughFDOconnections.Thismeansthatupdatesoccurimmediately.AutoCADMap3DworkswithdatastoredintheDWGfileaswellasFDOdata.Dependingonthemethodchosen,updatesinaAutoCADMap3Dapplicationmaybecachedandnotwrittendirectlytothefeaturesource.

DifferencesinoperationbetweenAutoCADMap3DandMapGuidemeanthatinsomecasestheGeospatialPlatformAPIhasadifferentimplementationintheproducts.AutoCADMap3DincludesasetofclassesthatextendtheAPI.Forexample,theGeospatialPlatformAPIhasanMgLayerBaseclass.AutoCADMap3DextendsthisintheAcMapLayerclass.

AllclassesthatarepartoftheGeospatialPlatformAPIbeginwiththeprefixMg.ClassesthatextendtheGeospatialPlatformAPIforuseinAutoCADMap3DbeginwiththeprefixAcMap.

AutoCADMap3DincludesthefollowingenumsthatarenotpartoftheGeospatialPlatformAPI:

EditMode

HighlightMode

AutoCADMap3Dalsoincludeseventhandling,whichisnotapartoftheGeospatialPlatformAPI.FormoredetailsseetheGeospatialPlatformSupplementReference.


GeospatialPlatformAPIDocumentation

ThedocumentationfortheGeospatialPlatformAPIisin3places:

AutoCADMap3DGeospatialPlatformDeveloper’sGuide(thisguide)

AutoCADMap3DGeospatialPlatformAPIReference

AutoCADMap3D.NETReferenceSupplement

TheGeospatialPlatformAPIreferencecontainsdocumentationaboutclassesandmethodsthatarecommontoAutoCADMap3DandMapGuide.WhenamethodbehavesdifferentlyinAutoCADMap3Dthisisnotedinthereference.

TheGeospatialPlatformSupplementReferencecontainsdocumentationaboutclassesandmethodsthatareusedonlywithinAutoCADMap3D.InmostcasestheclassesextendclassesintheGeospatialPlatformAPIReference.

TheGeospatialPlatformAPIworkswiththeFeatureDataObjects(FDO)API.FDOdocumentationisavailablewithAutoCADMap3D,bothintheproductinstallationhelpfolderandintheSDK.

Note TheAPIReferencesareavailableinCHMformat.TheDeveloper’sGuidesareavailableinPDFandCHMformat.ToviewallCHMdocumentationaspartofonehelpsystem,opensdk.doc.main.chm.


SettingUpVisualStudio

TousetheGeospatialPlatformAPI,followtheinstructionsintheAutoCADMap3DObjectARX.NETDeveloper’sGuide.Addthefollowingreferencetotheproject:

AcMapApiMgd.dll

ThisassemblycontainstheGeospatialPlatformAPIandaddsthenamespaceOSgeo.MapGuide.ItislocatedintheAutoCADMap3Dinstallationfolder.


SampleApplications

TheSDKincludessampleapplicationsintheMapSamples\Platformfolder.SeetheDeveloperSamplesGuidefordetails.ThesamplesserveasagoodintroductiontomanyaspectsoftheGeospatialPlatformAPIandcanbeusedasastartingpointfordevelopingcustomapplications.


Resources

Topicsinthissection

IntroductionWorkingWithResourcesDifferencesBetweenAutoCADMap3DandMapGuideSample-UsingResources


Introduction

IntheGeospatialPlatformAPI,resourcesarethefilesandconfigurationinformationnecessarytodrawlayersandmaps.Therearevarioustypesofresourcesrequired.Forexample,aFeatureSourcedescribesthelocation,type,andotherdetailsneededforaccesstoGISfeaturedata.ALayerDefinitiondefinesthedataandstyleforalayer.

Resourcesarestoredinaresourcerepository.AutoCADMap3DhasasinglerepositorynamedLibrary.ThisrepositoryiscontainedwithintheDWGfile.

MapGuideusesmultiplerepositories.TheLibraryrepositorycontainspersistent,site-widedata.ThereisasingleLibraryrepositoryforeachMapGuidesite.TherearemultipleSessionrepositories,eachonecontainingdatafromasingleMapGuidesession.Sessionrepositoriesareuniquetoanindividualsessionandcannotbeshared.AllMapGuiderepositoriesaremanagedonthesiteserver.

AllowableresourcetypesaredefinedasstaticmembersoftheclassMgResourceType.SomeresourcetypesapplyonlytoMapGuide.

ThefollowingresourcetypesarevalidforbothMap3DandMapGuide:

ResourceType Description

FeatureSource Containstherequiredparametersforconnectingtoageospatialfeaturesource.

LayerDefinition Containstherequiredparametersfordisplayingandstylingalayer.Layerscanbedrawinglayers,vectorlayers,orgrid(raster)layers.

SymbolDefinition Definesasymboltobedisplayedonamap.

ThefollowingresourcetypesareonlyvalidforMapGuide:

ResourceType Description

ApplicationDefinition DefinesaflexibleWeblayoutfortheFusionframework.

DrawingSource ContainstherequiredparametersforconnectingtoaDWGfile.

Folder Afolderintheresourcerepository.

LoadProcedure ContainstherequiredparametersforloadingnewdataintotheMapGuiderepository.

Map Containstherun-timedefinitionofamap.

MapDefinition Definesaninitialmapstate,usedasthebasisforcreatingarun-timemap.

PrintLayout DefinesthecomponentsofaprintedmapcreatedfromMapGuide.

Selection Containsselectioninformation.

SymbolLibrary Definesalibraryofsymbols.

WebLayout DefinesthecomponentsofaWeblayoutforaMapGuideViewer.

Resourcerepositoriesarestructuredlikedirectories,withfolders,subfolders,anddocuments.EachresourceisanXMLdocumentintherepository,namedwitha

uniqueresourceidentifier.Aresourceidentifierismadeupofthefollowingparts:

Repositorytype—either“Library”or“Session”.Map3Donlyuses“Library”.

Repositoryname—forlibraryrepositories,anemptystring.Forsessionrepositories,auniquesessionidentifierassignedbythesiteserver.

Path—thepathtothefoldercontainingtheresource.

Name—theresourcename,withouttheextension.

Resourcetype—theresourcetype(theextension).ThismustmatchoneoftheallowabletypesdefinedinMgResourceType.

Forexample,thefollowingcouldbeanameforafeaturesourceineitherMap3DorMapGuide:

Library://Samples/CityOutline.FeatureSource

ThefollowingcouldbeanameforamapdefinitioninMapGuide:

Session:70ea89fe-0000-1000-8000-005056c00008_en//Map.MapDefinition

ResourceService

Resourcesaremanagedbytheresourceservice,anMgResourceServiceobject.

InAutoCADMap3D,useAcMapServiceFactorytogettheresourceservice:

MgResourceServiceresourceService=

AcMapServiceFactory.GetService(MgServiceType.ResourceService)

asMgResourceService;

InMapGuide,useMgSiteConnectiontogettheresourceservice:

MgSiteConnectionsiteConnection=newMgSiteConnection();

siteConnection.Open(userInfo);

MgResourceServiceresourceService=

siteConnection.CreateService(MgServiceType.ResourceService)


ResourceDependencies

Resourcesmaydependonotheritems:

Someresourcesareselfsufficientanddonotrefertoanyotherresourcesorfiles.

Someresourcesreferenceotherresources.Forexample,layerdefinitionsandfeaturesourcesarestoredasseparateresources.Alayerdefinitionresourcecontainsareferencetotheresourcesforthefeaturesourcesthatareusedinthatlayer.

Someresourcesuseassociatedresourcedata.Forexample,thisisusedtostoreconfigurationinformationforODBC/WMS/Rasterfeaturesources.

ResourceSchemas

ResourcesarestoredintherepositoryasXMLdocuments.ApplicationsthataddormodifyresourcesmustensurethattheXMLvalidatesagainsttheappropriateschema.

ForAutoCADMap3D,theschemasareavailableaspartoftheSDK,intheSchemafolder.

ForMapGuide,theschemasareinstalledwiththeserverfiles,inInstallDir\Server\Schema.

TheschemasaredocumentedintheXMLSchemasmoduleoftheGeospatialPlatformReference.


WorkingWithResources

ResourcesintherepositorycanbemanagedbyusingtheMgByteSource,MgByteReader,andMgByteSinkobjects.

ToconvertastringrepresentationoftheXMLdataintodataforaresource,firstcreateanMgByteSource.NewMgByteSourceobjectscanbeinitializedwithastringorthecontentsofafile.GetanMgByteReaderfromthebytesourceandpassthattoMgResourceService.SetResource().

Forexample,ifanexternalfilecontainsthestringrepresentationoftheXMLforalayerdefinition,thefollowingwouldreadthecontentsofthefileandstoreitintherepository.

MgResourceIdentifierrID_layer=newMgResourceIdentifier(

@"Library://Data/Zoning.LayerDefinition");

MgByteSourcelayer_byteSource=newMgByteSource(xmlFilePath);

layer_byteSource.SetMimeType("text/xml");

resourceService.SetResource(rID_layer,

layer_byteSource.GetReader(),null);

TherearemanywaysofmodifyingtheXMLinaresource.Thebestmethodtouseinagivensituationdependsonthedevelopmentenvironment,thedeveloper’sfamiliaritywithagiventechnique,andthedesiredresult.Somepossibilitiesaredescribedinthefollowingsections.OthertechniquesforworkingwithXMLdataareequallyvalid.

xsd.exe

For.NETdevelopment,usedwithAutoCADMap3DandtheASP.NETAPIofMapGuide,itispossibletousethetoolxsd.exe,whichisavailablewiththeSDKthatcomeswithMicrosoftVisualStudio.xsd.exereadsanXMLschemaandgenerates.NETclassesforworkingwithXMLdocumentsbasedontheschema.xsd.execangeneratebothVB.NETandC#classes.

Tousexsd,atypicalcommandis:

xsd.exeLayerDefinition-1.0.0.xsd/c/l:cs/n:OSGeo.MapGuide.Schema.LayerDefinition

Foranexampleofhowtousetheseclasses,seetheDeveloperSamplesGuide.

Formoreinformationonxsd,seehttp://msdn.microsoft.com.

layerdefinitionfactory.php

MapGuideincludeslayerdefinitionfactory.php,whichcontainsPHPmethodsforworkingwiththeLayerDefinitionschema.Thesemethodsaredesignedtohandlemostbasictaskswithlayerdefinitions,butdonotprovidecompletesupportforallpossibilities.TheycreatetheXMLbysubstitutingstringsintoexternaltemplates.Itisrelativelyeasytoadaptthetechniquesfromlayerdefinitionfactory.phpforusewithadifferentschemaortotranslatethemintooneoftheotherdevelopmentlanguages.

AutodeskMapGuideStudio

OneofthesimplestwaystocreateXMLtemplatesistouseAutodeskMapGuideStudiowithAutodeskMapGuideEnterpriseorMapGuideOpenSource.UsingStudio,createtheresourceswiththedesiredvalues,thensavethemasXML.Theresultingfilecanbeeditedusingatexteditor,XMLeditor,orwithtechniqueslikethoseinlayerdefinitionfactory.php.

DocumentObjectModel

Finally,allofthedevelopmentlanguagessupportversionsoftheDocumentObjectModel(DOM)API,whichisageneral-purposeAPIforworkingwithandvalidatingXMLfiles.UsingtheDOMAPIrequiresconvertingdataintoastring,thenconvertingthatstringintoanXMLdocument.Forexample,thefollowingtakesresourcedatafromtherepositoryandloadsitintoanXMLdocument:

//usingSystem.Xml;

MgByteReaderbyteReader=

resourceService.GetResourceContent(resourceId);

XmlDocumentdoc=newXmlDocument();

doc.LoadXml(byteReader.ToString());

http://msdn.microsoft.com

ModifytheXMLdocumentusingstandardDOMmethods,thenconvertitbacktoastringandre-savetheresource.

StringxmlString=doc.DocumentElement.OuterXml;

resourceService.SetResource(resourceId,

newMgByteReader(xmlString,"text/xml"),null);


DifferencesBetweenAutoCADMap3DandMapGuide

ThePlatformAPIhasbeenmadetobeasconsistentaspossiblebetweenAutoCADMap3DandMapGuide.However,therearesomedifferences,especiallyinthewaytheyhandleresources.

AutoCADMap3DdoesnotuseApplicationDefinition,DrawingSource,Folder,LoadProcedure,Map,MapDefinition,PrintLayout,Selection,SymbolLibrary,orWebLayoutresources.

InAutoCADMap3D,theresourcesarestoredinsidetheDWGdrawingfileoraDWTtemplatedrawing,notinanexternaldatabase.Thismeansthatresourcesandtheirpathsarespecifictothatdrawing.Inotherwords,thesamerepositorypathinanotherdrawingmaynotbedefined,ormayrefertoadifferentresource.Ifyouneedtoshareresourcesbetweendrawings,youmustaddthemtoeachdrawing.

SessionrepositoriesarenotsupportedinAutoCADMap3D.AllresourcesmustbestoredintheLibraryrepository.

AutoCADMap3Ddoesnotuseresourceheaders.Foranymethodthatallowsthem,forexampleSetResource(),enternullforthatparameter.

ThefollowingmethodsinMgResourceServicearenotsupportedinAutoCADMap3D:

ApplyResourcePackage()

ChangeResourceOwner()

GetRepositoryContent()

GetRepositoryHeader()

GetResourceHeader()

UpdateRepository()

Themethodofspecifyingtheresourcedataforafilediffers.InMapGuide,theprocedureis:

1. InthefeaturesourceXML,providethenameoftheSDFfile.Forexample:

<Value>%MG_DATA_FILE_PATH%

HydrographicPolygons.sdf</Value>

2. UseResourceService.SetResourceData()tospecifythelocationoftheresourcedata(theSDFfile)ondisk.

InAutoCADMap3D,theprocedureistospecifytheabsolutelocationoftheresourcedatainthefeaturesourceXML.Forexample:

<Parameter>

<Name>File</Name>

<Value>C:\MapObjectARXSDK\MapSamples\Platform\BuildMap\Data\SDF\Buffered.sdf</Value>

</Parameter>

NocalltoResourceSerivce.SetResourceData()isrequired.AutoCADMap3DdoesuseResourceService.SetResourceData()forstreams,butonlyfortheconfigurationinformationforODBC/WMS/Rasterfeaturesources.


Sample-UsingResources

Thisexampleshowshowtoaddaresourceprogrammatically,usingexternalfilesthatcontaintheXMLfortheresources.

Topicsinthissection

TheXMLFilesAddingTheResourcePointsToWatch


TheXMLFiles

ThissampleusesdatafromtheBuildMapdevelopersample.WhenyourunBuildMap,itwritesthesefilestothedirectorycontainingBuildMap.dll.SeetheDeveloperSamplesGuidefordetails.

OnefileisZoning.layer.Thisspecifiesallthepropertiesfordrawingonelayerinamap.Notethe<ResourceId>element,whichreferstotheresourceforthefeaturesource.

<?xmlversion="1.0"encoding="utf-8"?>

<LayerDefinition

xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance"

xmlns:xsd="http://www.w3.org/2001/XMLSchema"

version="1.0.0">

<VectorLayerDefinition>

<ResourceId>Library://Data/SDF/Zoning.FeatureSource

</ResourceId>

<FeatureName>Schema:Zoning</FeatureName>

<FeatureNameType>FeatureClass</FeatureNameType>

<Geometry>Geometry</Geometry>

<VectorScaleRange>

<AreaTypeStyle>

<AreaRule>

<LegendLabel/>

<AreaSymbolization2D>

<Fill>

<FillPattern>Solid</FillPattern>

<ForegroundColor>a03cafda</ForegroundColor>

<BackgroundColor>FF000000</BackgroundColor>

</Fill>

<Stroke>

<LineStyle>Solid</LineStyle>

<Thickness>0.0</Thickness>

<Color>FF000000</Color>

<Unit>Centimeters</Unit>

</Stroke>

</AreaSymbolization2D>

</AreaRule>

</AreaTypeStyle>

</VectorScaleRange>

</VectorLayerDefinition>

</LayerDefinition>

ThesecondfileisZoning.FeatureSource,whichdefinesthepropertiesofanSDFfeaturesource.TheFileparameterpointstothelocationondisk.SeeFeatureServiceformoredetails.


<FeatureSourcexmlns:xsi="http://www.w3.org/2001/XMLSchema-instance"xmlns:xsd="http://www.w3.org/2001/XMLSchema">

<Provider>OSGeo.SDF.3.3</Provider>

<Parameter>

<Name>File</Name>

<Value>C:\Map3DSDK\MapSamples\Platform\BuildMap\Data\SDF\Zoning.sdf</Value>

</Parameter>

<Parameter>

<Name>ReadOnly</Name>

<Value>False</Value>

</Parameter>

</FeatureSource>


AddingTheResource

TousetheXMLfilestocreatethelayerandthefeaturesource,useMgResourceService.SetResource().Forexample:

//Addthelayerdefinition.

//Itwillbestoredintherepositoryusingtheresource

//identifier.

MgResourceIdentifierrID_layer=newMgResourceIdentifier(

@"Library://Data/Zoning.LayerDefinition");

//Note:Modifythisdirectorytopointtothelocationof

//theXMLfiles.

StringxmlDirectory=@"C:\Map3DSDK\"

+@"MapSamples\Platform\BuildMap\bin\Debug\";

//ReadtheXMLfile,thensaveitscontentsintheresource

//repository.

MgByteSourcelayer_byteSource=

newMgByteSource(xmlDirectory+"Zoning.layer");

layer_byteSource.SetMimeType("text/xml");

resourceService.SetResource(rID_layer,

layer_byteSource.GetReader(),null);

//Addthefeaturesource

//Note:ThelayerdefinitionXMLrefersto

//'Library://Data/SDF/Zoning.FeatureSource'so

//wemustusethatnamehere.

MgResourceIdentifierrID_feature_source=

newMgResourceIdentifier(

@"Library://Data/SDF/Zoning.FeatureSource");

MgByteSourcefeature_byteSource=new

MgByteSource(xmlDirectory+"Zoning.FeatureSource");

feature_byteSource.SetMimeType("text/xml");

resourceService.SetResource(rID_feature_source,

feature_byteSource.GetReader(),null);

Thenaddthelayertothecurrentmap.Forexample:

MgLayerBaselayer=AcMapLayer.Create(rID_layer,

resourceService);

layer.SetName("NewLayer");

AcMapMapcurrentMap=AcMapMap.GetCurrentMap();

currentMap.GetLayers().Add(layer);


PointsToWatch

InthefeaturesourceXML,theprovidername(forexample,OSGeo.SDF.3.3)mustmatchoneoftheprovidernameslistedintheoutputofMgFeatureService.GetFeatureProviders().

Inthelayerdefinition,theResourceIdvaluemustmatchthepathofthefeaturesource.Intheexampleabove,thispathisusedinthelayerdefinition:

<ResourceId>Library://Data/SDF/Zoning.FeatureSource

</ResourceId>

Sothecorrespondingpathmustbeusedwhenthefeaturesourceiscreated.Forexample:

MgResourceIdentifierrID_feature_source=


@"Library://Data/SDF/Zoning.FeatureSource");

CreatenewlayersusingthestaticmethodAcMapLayer.Create().

CreatenewlayergroupsusingtheAcMapLayerGroupconstructorAcMapLayerGroup(groupName).


FeatureService

Topicsinthissection

OverviewDefiningFeatureSourcesJoinsAddingFeatureClassestoaMapSelectingFeatureDataRepresentationofGeometrySelectingUsingtheAPIUpdatingFeaturesCreatingSDFfiles


Overview

AfeaturesourcerepresentsasingleFDO(FeatureDataObjects)connection.FDOisanAPIforreadingandwritinggeospatialdatainavarietyofformats.FormoredetailsaboutFDO,seethedocumentationincludedwithAutoCADMap3DandtheSDK,orvisitfdo.osgeo.org.

FeatureServiceprovidesacommonAPIforreadingandwritingfeaturedatafromdatasourcesforwhichanFDOproviderexists.

Differentfeaturesourceshavedifferentcapabilities.Forexample,anOracleSpatialdatabasewillhavemorecapabilitiesthananODBCconnection.Somefeaturesourcescanhavemultipleschemas.

Oneschemainafeaturesourcecandescribemultiplefeatureclasses.Forexample,asingleSDFfilecouldcontainafeatureclassforroadsandanotherfeatureclassforhydrography.

InAutoCADMap3D,asingleFDOfeatureclasscorrespondstoasinglemaplayer.Therecannotbemorethanonefeatureclassperlayer,andalayercontainingfeaturedatacannotcontainAcDbentities.

Note AllFeatureServiceoperationsworkwithfeaturesbelongingtothecurrentmap.Togetthecurrentmap,callAcMapMap.GetCurrentMap().


DefiningFeatureSources

TodefineafeaturesourcewithinAutoCADMap3D,createaresourceidentifierforthefeaturesourceandstoreitintheresourcerepository.ThencallMgResourceService.SetResource()withthreeparameters:

AnMgResourceIdentifierthatcontainsthepathintheresourcerepositoryfortheresource.

AnMgByteReaderthatprovidestheXMLdescribingthefeaturesource.ThisconformstoFeatureSource.xsd.

Anullparameterfortheresourceheader.ThisisnotusedbyAutoCADMap3D.

Therepositorypathisoftheform

Library://resourcePath/resourceName.FeatureSource

resourcePathisoptional,butFeatureSource(casesensitive)ismandatory.Forexample,thefollowingcreatesanMgResourceIdentifier:

MgResourceIdentifierparcelId=

newMgResourceIdentifier("Library://parcels.FeatureSource");

TheexactformoftheXMLdescribingthefeaturesourcevariesdependingontheFDOprovider.SeetheschemadocumentationforFeatureSource.xsdandtheConnectionAPIsectionofTheEssentialFDOfordetails.DifferentFDOprovidersacceptdifferentparameters,asdescribedinTheEssentialFDO.Forexample,theAutodesk.Raster.3.2provideracceptsasingleparameter,DefaultRasterFileLocation.ThisissetinaName/ValueparameterintheXMLdata.


<FeatureSource


xmlns:xsd="http://www.w3.org/2001/XMLSchema">

<Provider>Autodesk.Raster.3.2</Provider>

<Parameter>

<Name>DefaultRasterFileLocation</Name>

<Value>C:\some\folder\rasterfile.jpg</Value>

</Parameter>

<ConfigurationDocument>config://rasterfile.jpg

</ConfigurationDocument>

<LongTransaction/>

</FeatureSource>

Someprovidersrequireadditionalconfiguration.Forexample,theAutodesk.Raster.3.2providerrequiresgeoreferencinginformationtodefinethelocationandresolutionoftherasterdataforsomerasterfileformats.Thiscanbeinaworldfileinthesamefolderastherasterfile,oritcanbeinaseparateFDOconfigurationfile.WMSandODBCproviderscanalsorequireseparateconfigurationfiles.

Forthoseprovidersthatdorequireaconfigurationfile,theFeatureSourceXMLcontainsa<ConfigurationDocument>elementthatpointstoresourcedata.CallMgResourceService.SetResourceData()tosetthedata.Thedatanamemustmatchthenameinthe<ConfigurationDocument>element.TheBuildMapsampleusesconfig://aspartoftheresourcedataname,butthisisnotrequired.

Topicsinthissection

Example:DefiningaVectorFeatureSourceExample:DefiningaRasterFeatureSource


Example:DefiningaVectorFeatureSource

Definingavectorfeaturesourcerequirescreatingthefeaturesourcedefinitionandstoringitintheresourcerepositoryusingthefeaturesourceresourceidentifier.ThefollowingexampleassumesthatSDFpathisastringcontainingthefilepathofanSDFfile.ItcreatesafeaturesourcewitharesourceidentifierofLibrary://feature.FeatureSource.

Therearemanywaystocreateafeaturesourcedefinition.Onemethod,usedinthesampleapplicationsandthefollowingexample,usesclassesgeneratedusingtheVisualStudiotoolxsd.exeonFeatureSource.xsd.FeatureSourceTypeandNameValuePairTypeareclassesgeneratedthisway.

Note ResourceservicerequiresdatatobeUTF-8encoded.

//Gettheservices

MgResourceServicers;

rs=AcMapServiceFactory.GetService(MgServiceType.ResourceService)


MgFeatureServicefs;

fs=AcMapServiceFactory.GetService(MgServiceType.FeatureService)

asMgFeatureService;

MgResourceIdentifierfsId=newMgResourceIdentifier(

"Library://feature.FeatureSource");

//Createthefeaturesourcedefinitionwitharequired

//parameterofFileandanoptionalparameterofReadOnly

stringxmlString;

FeatureSourceTypefsType=newFeatureSourceType();

fsType.Provider="OSGeo.SDF.3.2";

NameValuePairTypeparam=newNameValuePairType();

param.Name="File";

param.Value=SDFpath;

NameValuePairTypeparam2=newNameValuePairType();

param2.Name="ReadOnly";

param2.Value="false";

fsType.Parameter=newNameValuePairType[]{param,param2};

//Serializethefeaturesourceobjectmodeltoxmlstring

using(StringWriterwriter=newStringWriter())

{

XmlSerializerxs=newXmlSerializer(fsType.GetType());

xs.Serialize(writer,fsType);

xmlString=writer.ToString();

}

//ConverttheUnicodestringtoUTF8bytesforResourceService

byte[]unicodeBytes=Encoding.Unicode.GetBytes(xmlString);

byte[]utf8Bytes=Encoding.Convert(Encoding.Unicode,

Encoding.UTF8,unicodeBytes);

//CreateabytereadercontainingtheXMLfeature

//sourcedefinition.Storethedefinitionintherepository

MgByteSourcexmlSource=newMgByteSource(utf8Bytes,

utf8Bytes.Length);

rs.SetResource(fsId,xmlSource.GetReader(),null);


Example:DefiningaRasterFeatureSource

Definingarasterfeaturesourceissimilartodefiningavectorfeaturesource.Theparametersvarydependingontheprovider.Mostrasterfilesdonotcontaincoordinatesysteminformation,soitmustbeobtainedsomeotherway.ThiscanbedoneusingaworldfileorthroughadditionalconfigurationfortheFDOprovider.Thefollowingexampleusesthesecondmethod,addingresourcedatacontainingtheconfigurationinformation.

Theresourceidentifiercontainsthelocationintheresourcerepositoryforthefeaturesourcedefinition.

MgResourceIdentifierrasterId=newMgResourceIdentifier(

"Library://rasterFeature.FeatureSource");

stringxmlString;

FeatureSourceTypefsType=newFeatureSourceType();

fsType.Provider="Autodesk.Raster.3.2";

NameValuePairTypeparam=newNameValuePairType();

param.Name="DefaultRasterFileLocation";

param.Value=@"C:\some\folder\rasterfile.jpg";

fsType.Parameter=newNameValuePairType[]{param};

fsType.ConfigurationDocument="config://rasterfile.jpg";

fsType.LongTransaction="";

//Serializethefeaturesourceobjectmodeltoanxmlstring


{

XmlSerializerxs=newXmlSerializer(fsType.GetType());

xs.Serialize(writer,fsType);

xmlString=writer.ToString();

}

byte[]unicodeBytes=Encoding.Unicode.GetBytes(xmlString);

byte[]utf8Bytes=Encoding.Convert(Encoding.Unicode,


MgByteSourcexmlSource=

newMgByteSource(utf8Bytes,utf8Bytes.Length);

MgResourceServicers;

rs=AcMapServiceFactory.GetService(MgServiceType.ResourceService)


rs.SetResource(rasterId,xmlSource.GetReader(),null);

TheconfigurationinformationvariesdependingontheFDOprovider.TheWMS,ODBC,andRasterprovidersmayneedadditionalconfigurationinformation.RefertotheFDOdocumentationintheMapSDKandintheAutoCADMap3Dinstallationfolderformoredetails.

Thefollowingreadstheconfigurationfromafileandstoresitintheresourcerepository.Ensurethatthedatanamematchesthe<ConfigurationDocument>elementinthefeaturesourcedefinition.

MgByteSourcesource;

source=newMgByteSource(@"C:\some\folder\rasterconfig.xml");

rs.SetResourceData(rasterId,"config://rasterfile.jpg",

MgResourceDataType.Stream,source.GetReader());


Joins

Joinsextendafeaturesourcebycombiningitwithdatafromanotherfeaturesource,similartoadatabasejoin.TheyarecommonlyusedtocombineGISdatawithdatafromadatabase.

Forexample,anSDFfilecontainingthefollowingproperties:

parcelgeometry

parcelID

couldbejoinedwithanODBCdatabasecontainingthefollowingproperties:

parcelID

ownername

assessmentvalue

landusedesignation

Thejoinisdefinedinthefeaturesourcedefinition.Eachjoinrequires2featureclasses.TheprimaryfeatureclasscontainsthegeometryfordisplayinAutoCADMap3D.Thesecondaryfeatureclassdoesnotneedgeometry,butitmusthaveapropertythatmatchesapropertyintheprimaryfeatureclass.Intheexampleabove,theSDFfilecontainstheprimaryfeatureclassandtheODBCdatabasecontainsthesecondaryfeatureclass.

Inmostcasesthefeatureclasseswillbefromdifferentfeaturesources,butitispossibletocreateaself-referencingjoinwithin1featureclassorajoinbetween2featureclassesinthesamefeaturesource.

Tocreateajoinedfeaturesource,beginwiththesecondaryfeaturesource.Thisdoesnotrequireanythingspecial.Forexample,thefollowingisasimpleconnectiontoanODBCdatabase:

<FeatureSource



xsi:noNamespaceSchemaLocation="MapFeatureSource-1.0.0.xsd"

version="1.0.0">

<Provider>OSGeo.ODBC.3.2</Provider>

<Parameter>

<Name>Password</Name>

<Value></Value>

</Parameter>

<Parameter>

<Name>GenerateDefaultGeometryProperty</Name>

<Value>false</Value>

</Parameter>

<Parameter>

<Name>ConnectionString</Name>

<Value></Value>

</Parameter>

<Parameter>

<Name>DataSourceName</Name>

<Value>OWNERS</Value>

</Parameter>

<Parameter>

<Name>UserId</Name>

<Value></Value>

</Parameter>

<ConfigurationDocument></ConfigurationDocument>

<LongTransaction></LongTransaction>

</FeatureSource>

Theprimaryfeaturesourcedefinesthejoin.Itmustidentifythesecondaryfeaturesourceandwhichpropertiesaretobeusedforthejoin.Forexample,thefollowingisafeaturesourcedefinitionforanSDFfilewithajointoanODBCdatabase:

<FeatureSource



xsi:noNamespaceSchemaLocation="MapFeatureSource-1.0.0.xsd"

version="1.0.0">

<Provider>OSGeo.SDF.3.2</Provider>

<Parameter>

<Name>ReadOnly</Name>

<Value>false</Value>

</Parameter>

<Parameter>

<Name>File</Name>

<Value>C:\some\folder\Parcels.sdf</Value>

</Parameter>

<ConfigurationDocument></ConfigurationDocument>

<LongTransaction></LongTransaction>

<Extension>

<Name>Parcels_Joins1</Name>

<FeatureClass>SHP_Schema:Parcels</FeatureClass>

<AttributeRelate>

<AttributeClass>Fdo:Parcels</AttributeClass>

<ResourceId>Library://ODBC_1</ResourceId>

<Name>Parcels</Name>

<AttributeNameDelimiter>|</AttributeNameDelimiter>

<RelateType>LeftOuter</RelateType>

<ForceOneToOne>true</ForceOneToOne>

<RelateProperty>

<FeatureClassProperty>APN</FeatureClassProperty>

<AttributeClassProperty>APN</AttributeClassProperty>

</RelateProperty>

</AttributeRelate>

</Extension>

</FeatureSource>

The<Extension>elementdefinesthejoin.<Name>isthenameofthejoin,usedinalayerdefinitionthatreferencesthefeaturesource.Ifafeaturesourcedefinesmorethanonejointheymusthavedifferentnames.<FeatureClass>isafeatureclassintheprimaryfeaturesource.

<AttributeRelate>definesajointoasinglefeaturesource.Itispossiblefortheprimaryfeaturesourcetohavejoinstomorethanonesecondaryfeaturesource.Thisisrepresentedbymultiple<AttributeRelate>elements.Asanexample,theownerinformationcouldbeinonedatabasetableandassessmentinformationcouldbeinanother.

Foreachjoin,<AttributeClass>definestheschemaandfeatureclassinthesecondaryfeaturesource.<ResourceId>istheresourceidentifier.<RelateType>isthetypeofjoin.ThisreleaseofAutoCADMap3Dsupportsleftouterjoinsandinnerjoins.

Thejoincanhavemultiple<RelateProperty>elements.Thesedefinethefieldsthatmustmatchforthejoin.

StorethefeaturesourcedefinitionusingMgResourceService.SetResource(),asdescribedinDefiningFeatureSources.


AddingFeatureClassestoaMap

Toaddafeatureclasstoamap,createalayerdefinitionforthenewlayerandaddittotheresourcerepository.CreateanAcMapLayerandsetitslayerdefinition.AddthelayertothemapusingAcMapMap.GetCurrentMap().GetLayers().Add().

Creatingthelayerdefinitionissimilartocreatingthefeaturesourcedefinition.SeeDefiningFeatureSources.ThelayerdefinitionusestheLayerDefinition.xsdschema,whichincludesstylinginformation.SeeLayerDefinitionfordetails.

The<FeatureName>elementinthelayerdefinitionisoftheform

schemaName:className

whereschemaNameandclassNamearevalidforthefeaturesource.CallMgFeatureService.GetSchemas()togettheschemanamesforafeaturesourceandMgFeatureService.GetClasses()togettheclassnamesforaschema.

Thefollowingexamplecreatesalayerdefinitionforarasterlayerandaddsthelayertothecurrentmap.


stringlayerDefName="Library://rasterlayer.LayerDefinition";

MgResourceIdentifierlayerId=new

MgResourceIdentifier(layerDefName);

//Useclassesfromxsd.exetobuildthelayer

definition

LayerDefinitionTypelayerDef=newLayerDefinitionType();

GridLayerDefinitionTypegridLayerDef=new

GridLayerDefinitionType();

layerDef.Item=gridLayerDef;

gridLayerDef.ResourceId=rasterId.ToString();

gridLayerDef.FeatureName="rasters:classname";

gridLayerDef.Geometry="Image";

GridScaleRangeType[]ranges=newGridScaleRangeType[1];

gridLayerDef.GridScaleRange=ranges;

ranges[0]=newGridScaleRangeType();

ranges[0].ColorStyle=newGridColorStylizationType();

GridColorRuleType[]colorRules=newGridColorRuleType[1];

ranges[0].ColorStyle.ColorRule=colorRules;

colorRules[0]=newGridColorRuleType();

colorRules[0].LegendLabel="";

colorRules[0].Color=newGridColorType();

colorRules[0].Color.ItemElementName=ItemChoiceType.Band;

colorRules[0].Color.Item="1";

ranges[0].RebuildFactor=1;

//SerializethelayerdefinitiontoXML

stringlayerDefString;


{

XmlSerializerxs=newXmlSerializer(layerDef.GetType());

xs.Serialize(writer,layerDef);

layerDefString=writer.ToString();

}

//ConvertUnicodetoUTF-8

unicodeBytes=Encoding.Unicode.GetBytes(layerDefString);

utf8Bytes=Encoding.Convert(Encoding.Unicode,Encoding.UTF8,

unicodeBytes);

//Createabytereadercontainingthelayer

sourcedefinition

xmlSource=newMgByteSource(utf8Bytes,utf8Bytes.Length);

rs.SetResource(layerId,xmlSource.GetReader(),null);

//AddthelayertotheMap

MgLayerBaselayer=newAcMapLayer(layerId,rs);

layer.Name="newLayer";

currentMap.GetLayers().Add(layer);

Thisaddsthenewlayertotheendofthelayercollection,atthetopofthedraworder.

Layerscanbeorganizedintogroups.Toaddalayertoagroupcall

AcMapLayer.SetGroup()withthegroupname.


SelectingFeatureData

IndividualfeatureswithinafeaturesourceareidentifiedbyuniquefeatureIDs.TheformoftheIDdependsonthefeaturesource.CallMgFeatureService.GetClassDefinition()togetthefeatureclassdefinition.CallMgClassDefinition.GetIdentityProperties()togetalistofallpropertiesthatareidentityproperties.

Togetthecurrentlyselectedfeaturesforamap,callAcMapMap.GetFeatureSelection().ThisreturnsanMgSelectionBaseobject.Asingleselectioncancontainfeaturesfrommultiplelayersandclasses.CallMgSelectionBase.GetLayers()togetalllayerscontainingselectedobjects,orselectanindividuallayer.

Forexample,tofindselectedfeaturesontheParcelslayer,


MgFeatureServicefs=

AcMapServiceFactory.GetService(MgServiceType.FeatureService)

asMgFeatureService;

MgLayerCollectionlayers=currentMap.GetLayers();

MgLayerBaseparcelsLayer=layers.GetItem("Parcels");

stringfcName=parcelsLayer.GetFeatureClassName();

MgSelectionBaseselection=currentMap.GetFeatureSelection();

stringselectionFilter=selection.GenerateFilter(parcelsLayer,

fcName);

MgFeatureQueryOptionsqueryOpts=newMgFeatureQueryOptions();

queryOpts.SetFilter(selectionFilter);

MgFeatureReaderfeatureReader;

MgResourceIdentifierfsId=new

MgResourceIdentifier(parcelsLayer.GetFeatureSourceId());

featureReader=fs.SelectFeatures(fsId,fcName,queryOpts);

AselectionconsistsofoneormorefeatureIDs.Toprocessthefeaturesina

selection,createanMgFeatureReaderthatcontainstheselectedfeatures,thencallMgFeatureReader.ReadNext()toadvancethroughthefeaturereader.TocreatetheMgFeatureReader()fortheselectedfeaturesinalayer,callMgSelectionBase.GenerateFilter(),whichcreatesafiltertoselectthefeatures.ThencreateandinitializeanMgFeatureQueryOptionsobject.Finally,callAcMapFeatureService.SelectFeatures().

AnMgFeatureReaderiteratesthroughalistoffeaturesfromasinglefeaturesource.Toadvancetothenextfeatureinthereader,callMgFeatureReader.ReadNext().


RepresentationofGeometry

AutoCADMap3Dcanrepresentgeometricdatain3differentforms:

AGFtextformat,whichisanextensionoftheOpenGeospatialConsortium(OGC)WellKnownText(WKT)format.Thisisusedtorepresentgeometryasacharacterstring.

BinaryAGFformat.TheisusedbytheFDOtechnologysupportingtheFeatureService.

Internalrepresentation,usingMgGeometryandclassesderivedfromit.

ToconvertbetweenAGFtextandtheinternalrepresentation,useanMgWktReaderWriterobject.CallMgWktReaderWriter.Read()toconvertAGFtexttoMgGeometry.CallMgWktReaderWriter.Write()toconvertMgGeometrytoAGFtext.

ToconvertbetweenbinaryAGFandtheinternalrepresentation,useanMgAgfReaderWriterobject.CallMgAgfReaderWriter.Read()toconvertbinaryAGFtoMgGeometry.CallMgAgfReaderWriter.Write()toconvertMgGeometrytobinaryAGF.

Forexample,ifyouhaveaWKTrepresentationofthegeometry,youcouldcreateageometryobjectasfollows:

MgWktReaderWriterwktReaderWriter=newMgWktReaderWriter();

MgGeometrygeometry=wktReaderWriter.Read(wktGeometry);


SelectingUsingtheAPI

SelectionscanbecreatedprogramaticallywiththePlatformAPI.Thisisdonebyqueryingdatainafeaturesource,creatingafeaturereaderthatcontainsthefeatures,thenconvertingthefeaturereadertoaselection(MgSelectionobject).

Tocreateafeaturereader,applyaselectionfiltertoafeatureclassinthefeaturesource.Aselectionfiltercanbeabasicfilter,aspatialfilter,oracombinationofthetwo.ThefilterisstoredinanMgFeatureQueryOptionsobject.

Basicfiltersareusedtoselectfeaturesbasedonthevaluesoffeatureproperties.Forexample,youcoulduseabasicfiltertoselectallroadsthathavefourormorelanes.

Spatialfiltersareusedtoselectfeaturesbasedontheirgeometry.Forexample,youcoulduseaspatialfiltertoselectallroadsthatintersectacertainarea.

Topicsinthissection

BasicFiltersSpatialFilters


BasicFilters

Basicfiltersperformlogicaltestsoffeatureproperties.Youcanconstructcomplexqueriesbycombiningexpressions.Expressionsusethecomparisonoperatorsbelow:

Operator Meaning

= Equality

<> Notequal

< Lessthan

<= Lessthanorequalto

> Greaterthan

>= Greaterthanorequalto

LIKE Usedforstringcomparisons.The“%”wildcardrepresentsanysequenceof0ormorecharacters.The“_”wildcardrepresentsanysinglecharacter.Forexample,“LIKESchmitt%”willsearchforanynamesbeginningwith“Schmitt”.

Thecomparisonoperatorscanbeusedwithnumericorstringproperties,exceptfortheLIKEoperator,whichcanonlybeusedwithstringproperties.

CombineormodifyexpressionswiththestandardbooleanoperatorsAND,OR,

andNOT.

Topicsinthissection

Examples


Examples

Theseexamplesassumethatthefeatureclassyouarequeryinghasanintegerpropertynamedyearandastringpropertynamedowner.Toselectallfeaturesnewerthan2001,createafilterlikethis:

MgFeatureQueryOptionsqueryOptions=newMgFeatureQueryOptions();

queryOptions.SetFilter("year>2001");

Toselectallfeaturesbuiltbetween2001and2004,createafilterlikethis:

queryOptions.SetFilter("year>=2001andyear<=2004");

ToselectallfeaturesownedbyDavisorDavies,createafilterlikethis:

queryOptions.SetFilter("ownerLIKE'Davi%s'");


SpatialFilters

Withspatialfilters,youcandocomparisonsusinggeometricproperties.Forexample,youcanselectallfeaturesthatareinsideanareaonthemap,orthatintersectanarea.

Therearetwowaysofusingspatialfilters:

Createaseparatespatialfiltertoapplytothefeaturesource,usingtheMgFeatureQueryOptions.SetSpatialFilter()method.

IncludespatialpropertiesinabasicfiltercreatedwiththeMgFeatureQueryOptions.SetFilter()method.

TheMgFeatureQueryOptions.SetSpatialFilter()methodrequiresanMgGeometryobjecttodefinethegeometryandaspatialoperationtocomparethefeaturepropertyandthegeometry.ThespatialoperationsaredefinedinclassMgFeatureSpatialOperations.

Toincludespatialpropertiesinabasicfilter,definethegeometryusingWKTformat.UsetheGEOMFROMTEXT()functioninthebasicfilter,alongwithoneofthefollowingspatialoperations:

CONTAINS

COVEREDBY

CROSSES

DISJOINT

EQUALS

INTERSECTS

OVERLAPS

TOUCHES

WITHIN

INSIDE

Note Thespatialoperationsarenotcasesensitive,so“CONTAINS”and“contains”producethesameresult.

Forexample,thefollowingselectsfeaturesthatcrossanarea:

queryOptions.SetFilter(

"SHPGEOMcrossesGEOMFROMTEXT("+wktGeom+")");

Thesamefilteringsyntaxcanbeusedinalayerdefinition,tocreatealayercontainingonlythosefeaturesthatpassthefilter.SeeFilteringLayersByGeometryfordetails.

Note Notallspatialoperationscanbeusedonallfeatures.ItdependsonthecapabilitiesoftheFDOproviderthatsuppliesthedata.Thisrestrictionappliestoseparatespatialfiltersandspatialpropertiesthatareusedinabasicfilter.

Topicsinthissection

CreatingGeometryObjectsFromFeatures


CreatingGeometryObjectsFromFeatures

Youmaywanttouseanexistingfeatureaspartofaspatialquery.Toretrievethefeature’sgeometryandconvertitintoanappropriateformatforaquery,performthefollowingsteps:

Createaquerythatwillselectthefeature.

QuerythefeatureclasscontainingthefeatureusingAcMapLayer.SelectFeatures()orMgFeatureService.SelectFeatures().

ObtainthefeaturefromthequeryusingtheMgFeatureReader.ReadNext()method.

GetthegeometrydatafromthefeatureusingtheMgFeatureReader.GetGeometry()method.ThisdataisinAGFbinaryformat.

ConverttheAGFdatatoanMgGeometryobjectusingtheMgAgfReaderWriter.Read()method.

Forexample,thefollowingsequencecreatesanMgGeometryobjectrepresentingtheboundariesofzone1inthelayernamed“zones”.ItcreatesanMgGeometryobjectandtheWKTrepresentationofthatobject.


MgLayerBaselayer=layers.GetItem("zones");

stringfsId=layer.GetFeatureSourceId();

stringclassName=layer.GetFeatureClassName();

MgFeatureQueryOptionsquery=

newMgFeatureQueryOptions();

query.SetFilter("ZONE_ID=1");

MgResourceIdentifierresId=

newMgResourceIdentifier(fsId);

MgFeatureReaderfeatureReader=

fs.SelectFeatures(resId,

className,query);

if(featureReader.ReadNext())

{

stringgeometryName=layer.GetFeatureGeometryName();

MgByteReadergeometryData=

featureReader.GetGeometry(geometryName);

MgAgfReaderWriteragfReaderWriter=newMgAgfReaderWriter();

MgGeometrygeometry=agfReaderWriter.Read(geometryData);

MgWktReaderWriterwktReaderWriter=newMgWktReaderWriter();

stringwkt=wktReaderWriter.Write(geometry);

}

ThefollowingassumesthatanotherfeatureclasshasageometrypropertySHPGEOM.ItusestheWKTstringinaquerytofindfeaturesintheotherfeatureclassthatintersectthezone:

MgFeatureQueryOptionsqueryOpts=newMgFeatureQueryOptions();

queryOpts.SetFilter("SHPGEOMintersectsGEOMFROMTEXT("+

wkt+")");


UpdatingFeatures

AllupdatestofeaturesinafeaturesourceareperformedusinganMgFeatureCommandCollection.Thefeaturecommandcollectioncancontaincommandstoaddnewfeatures,deleteexistingfeatures,updateexistingfeatures,lockfeatures,orunlockfeatures.

Toaddanewfeature,createanMgInsertFeaturesobject.MgInsertFeatureshastwoconstructors.OnehasanMgPropertyCollectionparameterandisusedtoinsertasinglefeature.TheotherhasanMgBatchPropertyCollectionparameterandisusedtoinsertmultiplefeaturesinasinglecommand.

TheMgPropertyCollectioncontainsvaluesforthefeatureproperties,includingthefeaturegeometryproperty.CreateanemptyMgPropertyCollection,thenaddpropertiesusingMgPropertyCollection.Add().Thedifferentpropertytypes,suchasMgGeometryPropertyorMgInt32Property,areallderivedfromthebaseclassMgProperty.

Mostfeatureclasseswillrequireageometryproperty,whichisusedtodisplaythefeature.Tocreateageometryproperty,startwithanMgGeometryobject.

ConverttheMgGeometrytobinaryAGFformatsuitableforFDO.

MgByteReadergeometryStream;

MgAgfReaderWriteragfReaderWriter=newMgAgfReaderWriter;

geometryStream=agfReaderWriter.Write(geometry);

Createapropertycollectiontocontainthefeatureproperties.Addthegeometryproperty.Addanyotherrequiredproperties.Thepropertynamesarecasesensitiveandmustmatchthenamesdefinedinthefeatureclass.

MgPropertyCollectionproperties=newMgPropertyCollection();

MgGeometryPropertygeomProp;

geomProp=newMgGeometryProperty("SHPGEOM",geometryStream);

properties.Add(geomProp);

Createafeaturecommandtoinsertthefeature,andaddittoafeaturecommandcollection.

MgFeatureCommandCollectioncommands=

newMgFeatureCommandCollection();

MgInsertFeaturesinsertCommand;

insertCommand=newMgInsertFeatures(className,properties);

commands.Add(insertCommand);

CallAcMapLayer.UpdateFeatures()toaddthenewfeature.

mapLayer.UpdateFeatures(commands);

Deletingandupdatingfeaturesissimilar.TheconstructorsforMgDeleteFeaturesandMgUpdateFeaturesrequiredifferentparameters,butthefeaturecommandscanbeaddedtothesameMgFeatureCommandCollection.

Topicsinthissection

EditSets


EditSets

Therearetwodifferentmodesforupdatestofeatures:

Editset

Directupdate

Note SomeFDOproviders,includingthefile-basedprovidersSDF,SHP,andraster,donotsupporteditsetmode.

UpdatesmadeusingeditsetmodearemadetotheworkingcopyinsidetheAutoCADMap3Dapplication,butarenotcommittedtothefeaturesource.Editsmadeusingdirectupdatearechangedinthefeaturesourceimmediately.

Therearetwomethodsforupdatingfeatures:

AcMapLayer.UpdateFeatures()

MgFeatureService.UpdateFeatures()

AcMapLayer.UpdateFeatures()worksdirectlywithfeaturesinthemaplayer.Thisisthepreferredmethodwhenworkingineditsetmode.

MgFeatureService.UpdateFeatures()updatesthefeaturesinthefeaturesource.Thismethodcanbeusedwhenthefeaturesourceisnotbeingdisplayedinalayer.Forexample,anAutoCADMap3DapplicationcouldcreateanSDFfilecontainingresultdatawithouteverhavingtodisplaythedata.

Tosettheupdatemodeforalayer,callAcMapLayer.SetEditSetMode().

Tocommitchangesmadeineditsetmode,callAcMapLayer.SaveFeatureChanges().Thisupdatesthefeaturesource.Todiscardthechanges,callAcMapLayer.DiscardFeatureChanges().


CreatingSDFfiles

Manygeospatialoperationsrequirecreatingnewlayers,addingfeaturestothelayers,andaddingthelayerstothemap.Thelayerscanbetemporaryorpermanent.InAutoCADMap3DthisishandledusingSDFfiles.

AnSDFfilecontainsasingleschemathatcandefinemultiplefeatureclasses.

TocreateanSDFfile,firstdefinetheschemaandanyfeatureclassesusedintheschema.Foreachfeatureclass,definealistofproperties.Inmostcases,thepropertiesshouldincludeanidentitypropertyandageometryproperty,aswellasanyotherproperties.

UsetheFDOAPItocreatetheschema.

ThefollowingcreatesasimpleschemawithanautogeneratedIDproperty,astringproperty,andageometryproperty.

//Createthefeatureclassdefinition

FeatureClassclassDefinition=

newFeatureClass("newClass","classdescription");

//Addanautogeneratedidentityproperty

DataPropertyDefinitionidProp=

newDataPropertyDefinition("id","propertydesc");

idProp.DataType=DataType.DataType_Int32;

idProp.IsAutoGenerated=true;

classDefinition.Properties.Add(idProp);

classDefinition.IdentityProperties.Add(idProp);

//Addanameproperty

DataPropertyDefinitionnameProp=

newDataPropertyDefinition("Name","propertydesc");

nameProp.DataType=DataType.DataType_String;

classDefinition.Properties.Add(nameProp);

//Addageometryproperty

GeometricPropertyDefinitiongeomProp=

newGeometricPropertyDefinition("SHPGEOM","propertydesc");

geomProp.GeometryTypes=MgGeometryType.Polygon;

classDefinition.Properties.Add(geomProp);

classDefinition.GeometryProperty=geomProp;

//Createtheschemaandaddtheclassdefinition

FeatureSchemaschema=

newFeatureSchema("SHP_Schema","Schemadescription");

schema.Classes.Add(classDefinition);

Oncetheschemahasbeencreated,usetheFDOAPItocreatetheSDFfile,setthespatialcontext,andapplytheschema.Thefollowingismodifiedfromtheutilityclassesinthesampleapplications.

//Setconnectionproperties

IConnectionPropertyDictionaryconnProperties=

conn.ConnectionInfo.ConnectionProperties;

connProperties.SetProperty("File",sdfPath);

connProperties.SetProperty("ReadOnly",false.ToString());

//Createdatastore,ie.SDFfile

ICreateDataStorecreateDSCmd=

conn.CreateCommand(CommandType.CommandType_CreateDataStore)

asICreateDataStore;

createDSCmd.DataStoreProperties.SetProperty("File",sdfPath);

createDSCmd.Execute();

try

{

//Opentheconnection

ConnectionStateconnState=conn.Open();

intretryRound=0;

while(++retryRound<5//Try5times

&&(connState==ConnectionState.ConnectionState_Pending

||connState==ConnectionState.ConnectionState_Busy))

{

connState=conn.Open();

}

if(retryRound>=5)

{

thrownew

InvalidOperationException("Failedtoconnecttofile"

+sdfPath);

}

//Createspatialcontext,includingcoordinate

system


stringmapSRS=currentMap.GetMapSRS();

ICreateSpatialContextcreateSCCmd=

conn.CreateCommand(CommandType.CommandType_CreateSpatialContext)

asICreateSpatialContext;

createSCCmd.CoordinateSystemWkt=mapSRS;

createSCCmd.Name="";

createSCCmd.CoordinateSystem=mapSRS;

createSCCmd.Extent=newbyte[]{0,0,0,0};

createSCCmd.Description="Description";

createSCCmd.XYTolerance=0.0;

createSCCmd.ZTolerance=0.0;

createSCCmd.Execute();

//Applyschema

if(schema.ElementState!=

SchemaElementState.SchemaElementState_Unchanged)

{

IApplySchemaapplySchemaCmd=

conn.CreateCommand(CommandType.CommandType_ApplySchema)

asIApplySchema;

applySchemaCmd.FeatureSchema=schema;

applySchemaCmd.Execute();

}

}

catch(System.Exceptione)

{

throwe;//Oraddexceptionhandling

}

finally

{

//Closeconnection

if(conn!=null)

{

conn.Close();

}

}


MapsandLayers

Topicsinthissection

OverviewBasicLayerPropertiesLayerGroupsLayerVisibilityManipulatingLayersLayerDefinition


Overview

Amapiscomposedoflayers,whereeachlayerrepresentsdatafromafeaturesource.

AutoCADMap3DandAutodeskMapGuidedifferinsomeofthewaystheyhandlemaplayers.BecauseMapGuideisaweb-basedmappingproduct,itmustcoordinatelayerdisplaybasedoninformationfromtheclientandtheserver.AutoCADMap3Dcanhandlealllayerdisplaydirectlyfromtheapplication.

Note TheGeospatialPlatformAPIdealsstrictlywithlayersfromFDOfeaturesources.IfamapinAutoCADMap3Dincludesotherlayers,theymustbehandledusingtheappropriatemethodsfromthe.NETAPI.

Alayer(AcMapLayerobject),hasaLayerDefinitionpropertythatpointstoalayerdefinitionintheresourcerepository.ThelayerdefinitioncontentisXMLthatconformstotheLayerDefinition.xsdLayerDefinition.xsdschema.Amongotherelements,itcontainsaResourceIdelementthatidentifiesthefeaturesourceforthelayer.


ms-its:sdk.ref.gis.platform.chm::/xml_schemas/LayerDefinition/LayerDefinition.html

BasicLayerProperties

Amapcontainsoneormorelayers(AcMapLayerobjects)thatarerenderedtocreateacompositeimage.TheAcMapLayerclass,whichappliesonlytoAutoCADMap3D,isderivedfromMgLayerBase,whichispartofthecommonGeospatialPlatformAPIsharedbetweenAutoCADMap3DandMapGuide.

Eachlayerhaspropertiesthatdeterminehowitdisplaysinthemapandmaplegend.Someofthepropertiesare:

Layername:Auniqueidentifier

Visibility:whetherthelayershouldbedisplayedinthemap.Notethatactualvisibilityisdependentonmorethanjustthevisibilitysettingforalayer.SeeLayerVisibilityforfurtherdetails.

Selectable:Whetherfeaturesinthelayerareselectable.Thisonlyappliestolayerscontainingfeaturedata.Itdoesnotapplytolayerscontainingrasterdata.

AcMapMap.GetLayers()returnsanMgLayerCollectionobjectthatcontainsallthelayersinthemap.MgLayerCollection.GetItem()returnsanindividualMgLayerBaseobject,byeitherindexnumberinthecollectionorlayername.

Layersinthecollectionaresortedbydrawingorder,withthetoplayersatthebeginningofthecollection.


LayerGroups

Layerscanbeoptionallygroupedintolayergroups.LayersinthesamegrouparedisplayedtogetherintheDisplayManager.

Thevisibilityforalllayersinagroupcanbesetatthegrouplevel.Ifthegroupvisibilityisturnedoffthennoneofthelayersinthegroupwillbevisible,regardlessoftheirindividualvisibilitysettings.Ifthegroupvisibilityisturnedon,thenindividuallayerswithinthegroupcanbemadevisibleornotvisibleseparately.

Layergroupscanbenestedsoagroupcancontainothergroups.Thisprovidesafinerlevelofcontrolforhandlinglayervisibilityorforgroupinglayersintolegendgroups.

AcMapMap.GetLayerGroups()returnsanMgLayerGroupCollectionobjectthatcontainsallthetop-levellayergroupsinthemap.

Eachlayergroupinamapmusthaveauniquename,evenifitisnestedwithinanothergroup.


LayerVisibility

Whetheralayerisvisibleinagivenmapdependsonthreecriteria:

Thevisibilitysettingforthelayer

Thevisibilitysettingsforanygroupsthatcontainthelayer

Themapviewscaleandthelayerdefinitionforthatviewscale

Inorderforalayertobevisible,itslayervisibilitymustbeon,thevisibilityforanygroupcontainingthelayermustbeon,andthelayermusthaveastylesettingdefinedforthecurrentmapviewscale.

Topicsinthissection

Example:ActualVisibility


Example:ActualVisibility

Forexample,assumethatthereisalayernamedRoadsthatispartofthelayergroupTransportation.Thelayerhasviewstyledefinedforthescaleranges0–10000and10000–24000.

Thefollowingtableshowssomepossiblesettingsofthevariousvisibilityandviewscalesettings,andtheireffectontheactuallayervisibility.

LayerVisibility GroupVisibility ViewScale

ActualVisibility

On On 10000 On

On On 25000 Off

On Off 10000 Off

Off On 10000 Off


ManipulatingLayers

ModifyingbasiclayerpropertiesandchanginglayervisibilitysettingscanbedonedirectlybysettingpropertieslikeAcMapLayer.Name,AcMapLayer.Selectable,andAcMapLayer.Visible.Morecomplexmanipulationrequiresmodifyinglayerresourcesintheresourcerepository.

Topicsinthissection

ChangingVisibility


ChangingVisibility

Toquerytheactuallayervisibility,callAcMapLayer.IsVisible().Thereisnomethodtosetactualvisibilitybecauseitdependsonothervisibilitysettings.

Toquerythevisibilitysettingforalayer,callAcMapLayer.GetVisible().Tochangethevisibilitysettingforalayer,callAcMapLayer.SetVisible().

Toquerythevisibilitysettingforalayergroup,callAcMapLayerGroup.GetVisible().Tochangethevisibilitysettingforalayergroup,useAcMapLayerGroup.SetVisible().

Tochangethelayervisibilityforagivenviewscale,modifythelayerresourceandsaveitbacktotherepository.


LayerDefinition

ThefeaturesourceandstylingforalayeraresetusingaLayerDefinition,storedintheresourcerepository.ThelayerdefinitionconformstotheLayerDefinition.xsdLayerDefinition.xsdschema.Rasterlayersandvectorlayershavedifferentstylingrequirementsandcapabilities.

Forbothrasterandvectordata,asinglelayerdefinitioncancontainmultiplescaleranges,whichdefinethestylingforparticularviewscales.Forexample,avectorlayercouldhavethefollowingscaleranges:

0to10,000

10,000to500,000

500,000toinfinity

Featuresinthelayercouldbestyleddifferentlyorbehiddencompletelyforthedifferentscaleranges.

Foraavectorlayer,eachscalerangecancontainstylinginformationforthefollowing:

AreaTypeStyle,usedforpolygons

LineTypeStyle,usedforlinesandcurves

PointTypeStyle,usedforpoints

ThelayerdefinitioncanbeanyvalidXMLthatconformstotheschema.TohelpgeneratetheXML,theAutoCADMap3DsamplesuseclassesgeneratedfromLayerDefinition.xsdbyxsd.exe.

Forexample,tocreateavectorlayerdefinitionthatcontains2scaleranges,dothefollowing:

Createthetwoscaleranges.Foreach,specifytheminimumandmaximumscalefortherange.Definethenecessaryelements,likefill

ms-its:sdk.ref.gis.platform.chm::/xml_schemas/LayerDefinition/LayerDefinition.html

andstrokesettings.

Createthevectorlayerdefinition.Addthescaleranges.

Setthefeaturenametotheschema/featureclassinthefeaturesource.

Settheresourceidtopointtothefeaturesourcecontainingthelayerdata.

Setthegeometrytothegeometrypropertyofthefeatureclass.

Createalayerdefinitionthatcontainsthevectorlayerdefinition.

Storethelayerdefinitionintheresourcerepository.

Createanewlayerthatreferencesthelayerdefinition.Addthelayertothelayercollectionforthecurrentmap.

Theexamplecodethatfollowsusesthefollowingnamespacedeclarations:

usingSystem.IO(fortheStringWriterclass)

usingSystem.Text(fortheEncodingclass)

usingSystem.Xml.Serialization(forXMLserializationroutines)

usingOSGeo.MapGuide.Schema.LayerDefinition

(generatedbyxsd.exe.CodeforthisclassisavailablewiththeAutoCADMap3Dsamples.)

Thefollowingassumesthatthefeaturesourcecontainsonlypolygons.Featuresourcescontaininglineorpointdatawouldrequirestylingforthosefeaturetypesaswell.

//Createthefirstscalerange

VectorScaleRangeTyperange=newVectorScaleRangeType();

AreaRuleareaRule=newAreaRule();

AreaSymbolizationFillTypeareaSymFillType=

newAreaSymbolizationFillType();

FillTypefillType=newFillType();

fillType.FillPattern="Solid";

fillType.ForegroundColor="9900ffaa";

fillType.BackgroundColor="FF000000";

StrokeTypestrokeType=newStrokeType();

strokeType.LineStyle="Solid";

strokeType.Thickness="0.0";

strokeType.Color="FF000000";

strokeType.Unit=LengthUnitType.Centimeters;

areaSymFillType.Fill=fillType;

areaSymFillType.Stroke=strokeType;

areaRule.Item=areaSymFillType;

areaRule.LegendLabel="";

object[]items=newobject[1];

items[0]=newAreaRule[]{areaRule};

range.Items=items;

range.MinScale=0.0;

range.MaxScale=10000000.0;

range.MinScaleSpecified=true;

range.MaxScaleSpecified=true;

//Secondscalerange

VectorScaleRangeTyperange2=newVectorScaleRangeType();

AreaRuleareaRule2=newAreaRule();

AreaSymbolizationFillTypeareaSymFillType2=

newAreaSymbolizationFillType();

FillTypefillType2=newFillType();

fillType2.FillPattern="Solid";

fillType2.ForegroundColor="ffffff00";

fillType2.BackgroundColor="FF000000";

StrokeTypestrokeType2=newStrokeType();

strokeType2.LineStyle="Solid";

strokeType2.Thickness="0.0";

strokeType2.Color="FF000000";

strokeType2.Unit=LengthUnitType.Centimeters;

areaSymFillType2.Fill=fillType2;

areaSymFillType2.Stroke=strokeType2;

areaRule2.Item=areaSymFillType2;

areaRule2.LegendLabel="";

object[]items2=newobject[1];

items2[0]=newAreaRule[]{areaRule2};

range2.Items=items2;

range2.MinScale=10000000.0;

range2.MaxScale=Double.MaxValue;

range2.MinScaleSpecified=true;

range2.MaxScaleSpecified=true;

//Nowcreateavectorlayerdefinitionandadd

thescaleranges.

VectorLayerDefinitionTypevectorLayerDef=

newVectorLayerDefinitionType();

vectorLayerDef.VectorScaleRange=newVectorScaleRangeType[2];

vectorLayerDef.VectorScaleRange.SetValue(range,0);

vectorLayerDef.VectorScaleRange.SetValue(range2,1);

//Settheresourceidtopointtothefeature

sourcefor

//thelayer.Setthefeaturenametoafeature

classin

//thefeaturesource.Setthegeometryproperty

tothe

//defaultgeometrypropertyforthefeature

class.

vectorLayerDef.ResourceId="Library://Data/SAMPLE.FeatureSource";

vectorLayerDef.FeatureName="Schema1:FeatureClass1";

vectorLayerDef.Geometry="Geometry";

//Createalayerdefinitioncontainingthevector

layer

//definition.

LayerDefinitionlayerDef=newLayerDefinition();

layerDef.Item=vectorLayerDef;

layerDef.version="1.0.0";

//ConverttoanXMLstring.


{

XmlSerializerxs=newXmlSerializer(typeof(LayerDefinition));

xs.Serialize(writer,layerDef);

//ConverttoUTF-8.

byte[]unicodeBytes=

Encoding.Unicode.GetBytes(writer.ToString());

byte[]utf8Bytes=

Encoding.Convert(Encoding.Unicode,Encoding.UTF8,

unicodeBytes);

MgByteSourcesource=


//UpdatetheresourceinMap.

MgResourceServicers=



//Storethelayerdefinitionintherepository.

MgResourceIdentifiernewLayerDefId=


"Library://myNewLayer.LayerDefinition");

rs.SetResource(newLayerDefId,source.GetReader(),null);

//Createanewlayerthatreferencesthelayer

definition.

//Addthistothelayersinthecurrentmap.



AcMapLayerlayer;

layer=newAcMapLayer(newLayerDefId,rs);

layer.Name="testlayer";

layers.Add(layer);

}

ThiscreatesthefollowingXML:


<LayerDefinition



version="1.0.0">


<ResourceId>Library://Data/SAMPLE.FeatureSource</ResourceId>

<FeatureName>Schema1:FeatureClass1</FeatureName>

<FeatureNameType>FeatureClass</FeatureNameType>

<Geometry>Geometry</Geometry>

<VectorScaleRange>

<MinScale>0</MinScale>

<MaxScale>10000000</MaxScale>

<AreaTypeStyle>

<AreaRule>

<LegendLabel/>


<Fill>


<ForegroundColor>9900ffaa</ForegroundColor>


</Fill>

<Stroke>





</Stroke>


</AreaRule>

</AreaTypeStyle>

</VectorScaleRange>

<VectorScaleRange>

<MinScale>10000000</MinScale>

<MaxScale>1.7976931348623157E+308</MaxScale>

<AreaTypeStyle>

<AreaRule>

<LegendLabel/>


<Fill>


<ForegroundColor>ffffff00</ForegroundColor>


</Fill>

<Stroke>





</Stroke>


</AreaRule>

</AreaTypeStyle>

</VectorScaleRange>

</VectorLayerDefinition>

</LayerDefinition>

Topicsinthissection

LayersWithJoinedFeatureSourcesFilteringLayersByGeometryModifyingLayerStyle


LayersWithJoinedFeatureSources

Tocreatealayerdefinitionforalayerthatusesafeaturesourcecontainingajoin,createthelayerdefinitionasdescribedinLayerDefinition.Setthe<FeatureName>elementtothejoinnameasdefinedinthefeaturesource.Setthe<FeatureNameType>elementtoNamedExtension.Forexample,thefollowingportionofalayerdefinitionusesthejoinnamed“Parcels_Joins1”.


<LayerDefinition



version="1.0.0">


<ResourceId>Library://Data/SAMPLE.FeatureSource</ResourceId>

<FeatureName>Parcels_Joins1</FeatureName>

<FeatureNameType>NamedExtension</FeatureNameType>

SeeJoinsfordetailsaboutthefeaturesourcedefinition.


FilteringLayersByGeometry

Thelayerdefinitionforavectorlayercanincludea<Filter>elementtoselectonlycertainfeatures.ThefilterisastringthatcontainsavalidFDOselectionexpression.SeeSelectingUsingtheAPIforadescriptionoffilters.

Forexample,assumethefollowing:

geomPolyisanMgPolygonrepresentingtheareaofinterest.

geometryisthedefaultgeometrypropertyforafeatureclass.

Thefollowingcreatesafiltertoselectonlythosefeaturesthatintersectthepolygon.

MgWktReaderWriterrw=newMgWktReaderWriter();

stringwktGeom=rw.Write(geomPoly);

stringfilter="geometryintersectsGeomFromText("+

wktGeom+")");

TomodifythesampleinLayerDefinitiontousethefilter,setthe<Filter>elementasfollows:

vectorLayerDef.Filter=filter;


ModifyingLayerStyle

Tomodifythestylingforalayer,retrievethelayerdefinitionfromtherepository,makechangestoit,storeitbacktotherepository,andrefreshthelayer.

Toretrievethelayerdefinition,getitsresourceidentifierfromthemaplayer.GettheresourcecontentanddeserializeitusinganXmlSerializerobject.



MgResourceServicers=



//Getthelayerdefinition.ConvertittoanXMLstring

//storedinabytereader.

AcMapLayerlayer1=layers.GetItem(layerName)asAcMapLayer;

MgResourceIdentifierlayerDefId=layer1.GetLayerDefinition();

MgByteReaderlayerReader=rs.GetResourceContent(layerDefId);

//DeserializeittocreateaLayerDefinitionobject.

XmlSerializerlayerDefSerializer=new

XmlSerializer(typeof(LayerDefinition));

LayerDefinitionxmlLayerDef=

layerDefSerializer.Deserialize(new

StringReader(layerReader.ToString()))

asLayerDefinition;

UpdatingtheLayerDefinitionobjectissimilartocreatinganewone.Findthecorrectelementsandsettheirvalues.Forexample,thefollowingchangestheforegroundcolorforthearearuleinthefirstscalerange,thenitupdatesthelayerdefinitionintheresourcerepositoryandrefreshesthelayer.

//ShouldbeaVectorLayerDefinitionType

if(xmlLayerDef.ItemisVectorLayerDefinitionType)

{

VectorLayerDefinitionTypexmlVectorLayerDef=

xmlLayerDef.ItemasVectorLayerDefinitionType;

//Checktherulesforthefirstscalerange.

//Onlyupdaterulesiftheyarethecorrecttype.

object[]items=xmlVectorLayerDef.VectorScaleRange[0].Items;

foreach(objectiteminitems)

{

Typetype=item.GetType();

if(type.Name==typeof(AreaRule[]).Name)

{

AreaRule[]areaRules=itemasAreaRule[];

//OK,gotthecorrectarearule.Settheforegroundcolor.

if(areaRules.Length>0)

{

areaRules[0].Item.Fill.ForegroundColor=newColor;

}

}

}

//NowconvertitbacktoanXMLstringandupdatethe

//resource.


{

//Getthexmlstring

layerDefSerializer.Serialize(writer,xmlLayerDef);

//Createtheresource

byte[]unicodeBytes=

Encoding.Unicode.GetBytes(writer.ToString());

byte[]utf8Bytes=

Encoding.Convert(Encoding.Unicode,


MgByteSourcesource=


//UpdatetheresourceinMap

rs.SetResource(layer1.LayerDefinition,

source.GetReader(),null);

layer1.ForceRefresh();

}

}


Geometry

Topicsinthissection

OverviewGeometryObjectsComparingGeometryObjectsCoordinateSystemsMeasuringDistanceCreatingaBuffer


Overview

TheAutoCADMap3DGeospatialPlatformAPIincludesacompletesetofclassesforworkingwithgeometry.Thisincludesthefollowing:

Describingsimpleandcomplexgeometricobjects

Performingspatialcomparisonsbetweenobjects

Creatingnewobjectsbasedontheintersection,difference,orunionofexistingobjects

Convertingbetweendifferentcoordinatesystems

Creatingbuffersaroundobjects


GeometryObjects

MgGeometryisthebaseclassforallthegeometrytypes.Thesimplegeometrytypesare:

MgPoint—asinglepoint

MgLineString—aseriesofconnectedlinesegments

MgCurveString—aseriesofconnectedcurvesegments

MgPolygon—apolygonwithsidesformedfromlinesegments

MgCurvePolygon—apolygonwithsidesformedfromcurvesegments

Thecurvesegmentsarecirculararcs,definedbyastartpoint,anendpoint,andacontrolpoint.

Complextypesareformedbyaggregatingsimpletypes.Thecomplextypesare:

MgMultiPoint—agroupofpoints

MgMultiLineString—agroupoflinestrings

MgMultiCurveString—agroupofcurvestrings

MgMultiPolygon—agroupofpolygons

MgMultiCurvePolygon—agroupofcurvepolygons

MgMultiGeometry—agroupofsimplegeometryobjectsofanytype


ComparingGeometryObjects

TheMgGeometryclasscontainsmethodsforcomparingdifferentgeometryobjects.ThesearesimilartothespatialfiltersdescribedinSelectingUsingtheAPI.Methodstotestspatialrelationshipsinclude:

Contains()

Crosses()

Disjoint()

Equals()

Intersects()

Overlaps()

Touches()

Within()

Forexample,ifyouhaveanMgLineStringobjectlineandanMgPolygonobjectpolygon,youcantestifthelinecrossesthepolygonwithacallto

line.Crosses(polygon)

Methodstocreatenewgeometryobjectsfromthepointsetoftwoothergeometriesinclude:

Difference()

Intersection()

SymmetricDifference()

Union()

CompletedetailsareintheGeometrymoduleoftheGeospatialPlatformAPIreference,underSpatialRelationships.


CoordinateSystems

Asinglemapwilloftencombinedatafromdifferentsources,andthedifferentsourcesmayusedifferentcoordinatesystems.Themaphasitsowncoordinatesystem,andanyfeaturesourcesusedinthemapmayhavedifferentcoordinatesystems.Itisimportantfordisplayandanalysisthatalllocationsaretransformedtothesamecoordinatesystem.

Note Acoordinatesystemcanalsobecalledaspatialreferencesystem(SRS)oracoordinatereferencesystem(CRS).ThisguideusestheabbreviationSRS.

AutoCADMap3Dsupportsthreedifferenttypesofcoordinatesystem:

ArbitraryX-Y

Geographic,orlatitude/longitude

Projected

AnMgCoordinateSystemobjectrepresentsacoordinatesystem.

Note YoucannottransformbetweenarbitraryX-Ycoordinatesandeithergeographicorprojectedcoordinates.

TocreateanMgCoordinateSystemobjectfromanAcMapMapobject,

GettheWKTrepresentationofthemapcoordinatesystem,usingAcMapMap.GetMapSRS().

CreateanMgCoordinateSystemobject,usingMgCoordinateSystemFactory.Create().

TocreateanMgCoordinateSystemobjectfromamaplayer,

Getthefeaturesourceforthelayer.

Gettheactivespatialcontextforthefeaturesource.

ConvertthespatialcontexttoaWKT.

CreateanMgCoordinateSystemobjectfromtheWKT.

Totransformgeometryfromonecoordinatesystemtoanother,createanMgCoordinateSystemTransformobjectusingthetwocoordinatesystems.ApplythistransformtotheMgGeometryobject.

Forexample,ifyouhavegeometryrepresentingafeatureonalayerthatusesonecoordinatesystem,andyouwanttocompareittoafeatureonanotherlayerthatusesadifferentcoordinatesystem,performthefollowingsteps:

stringfeatureSource1=layer1.GetFeatureSourceId();

MgSpatialContextsReadercontexts1=

featureService.GetSpatialContexts(

featureSource1,true);

contexts1.ReadNext();

stringsrs1=contexts1.GetCoordinateSystemWkt();

stringfeatureSource2=layer2.GetFeatureSourceId();

MgSpatialContextsReadercontexts2=

featureService.GetSpatialContexts(

featureSource2,true);

contexts2.ReadNext();

stringsrs2=contexts2.GetCoordinateSystemWkt();

MgCoordinateSystemFactorycoordsysFactory=

newMgCoordinateSystemFactory();

MgCoordinateSystemTransformxform=

coordsysFactory.GetTransform(srs1,srs2);

MgGeometrygeometry1xform=geometry1.Transform(xform);


MeasuringDistance

Measuringdistanceingeographicorprojectedcoordinatesystemsrequiresgreatcirclecalculations.BothMgGeometry.Buffer()andMgGeometry.Distance()acceptameasurementparameterthatdefinesthegreatcircletobeused.Ifthemeasurementparameterisnull,thecalculationisdoneusingalinearalgorithm.

Createthemeasurementparameter,anMgCoordinateSystemMeasureobject,fromtheMgCoordinateSystemobject.

DistanceiscalculatedintheunitsoftheSRS.MgCoordinateSystemincludestwomethods,ConvertCoordinateSystemUnitsToMeters()andConvertMetersToCoordinateSystemUnits(),toconverttoandfromlineardistances.

Forexample,tocalculatethedistancebetweentwoMgGeometryobjectsaandb,usingthecoordinatesystemsrs,performthefollowingsteps:

MgCoordinateSystemMeasuremeasure=srs.GetMeasure();

doubledistInMapUnits=a.Distance(b,measure);

doubledistInMeters=srs.ConvertCoordinateSystemUnitsToMeters(

distInMapUnits);

AnotherwaytocalculatethedistanceistouseMgCoordinateSystemMeasure.GetDistance(),asinthefollowing:

distInMapUnits=measure.GetDistance(a,b);


CreatingaBuffer

Tocreateabufferaroundafeature,usetheMgGeometry.Buffer()method.ThisreturnsanMgGeometryobjectthatyoucanuseforfurtheranalysis.Forexample,youcoulddisplaythebufferbycreatingafeatureinatemporaryfeaturesourceandaddinganewlayertothemap.Youcouldalsousethebuffergeometryaspartofaspatialfilter.Forexample,youmightwanttofindallthefeatureswithinthebufferzonethatmatchcertaincriteria,oryoumightwanttofindallroadsthatcrossthebufferzone.

Tocreateabuffer,getthegeometryofthefeaturetobebuffered.IfthefeatureisbeingprocessedinanMgFeatureReaderaspartofaselection,thisrequiresgettingthegeometrydatafromthefeaturereaderandconvertingittoanMgGeometryobject.Forexample:

MgByteReadergeometryData=

featureReader.GetGeometry(geometryName);

MgGeometryfeatureGeometry=agfReaderWriter.Read(geometryData);

Ifthebufferistobecalculatedusingcoordinatesystemunits,createanMgCoordinateSystemMeasureobjectfromthecoordinatesystemforthemap.Forexample:

stringmapWktSrs=currentMap.GetMapSRS();

MgCoordinateSystemFactorycoordSysFactory=

newMgCoordinateSystemFactory();

MgCoordinateSystemsrs=coordSysFactory.Create(mapWktSrs);

MgCoordinateSystemMeasuresrsMeasure=srs.GetMeasure();

Usethecoordinatesystemmeasuretodeterminethebuffersizeinthecoordinatesystem,andcreatethebufferobjectfromthegeometrytobebuffered.

doublesrsDist=

srs.ConvertMetersToCoordinateSystemUnits(bufferDist);

MgGeometrybufferGeometry=

featureGeometry.Buffer(srsDist,srsMeasure);

Todisplaythebufferinthemap,performthefollowingsteps:

Createafeaturesourceforthebuffer.Thismayrequirecreatinganewfileforthefeaturesource.SeeCreatingSDFfiles.

Createalayerthatreferencesthefeaturesource.Addittothemapandmakeitvisible.

Createanewfeatureusingthebuffergeometryandinsertitintothefeaturesource.

Forexample,thefollowingcodeassumesthatthelayerresLayerhasbeencreatedusingafeaturesourcewithageometrypropertyofGeometry.Itaddsanewfeatureusingthebuffergeometry.

MgPropertyCollectionproperties=newMgPropertyCollection();

properties.Add(newMgGeometryProperty("Geometry",

agfReaderWriter.Write(bufferGeometry)));

MgFeatureCommandCollectioncommands=

newMgFeatureCommandCollection();

commands.Add(newMgInsertFeatures(resFeatureClassName,

properties));

resLayer.UpdateFeatures(commands);

Tousethebufferaspartofaquery,createaspatialfilterusingthebuffergeometry,andusethisinacalltoAcMapLayer.SelectFeatures().Forexample,thefollowingcodeusesabasicfilterandaspatialfiltertoselectparcelsinsidethebufferareathatareoftype“MFG”.YoucanusetheMgFeatureReadertoperformtaskslikegeneratingareportoftheparcels,orcreatinganewlayerthatputspointmarkersoneachparcel.

MgFeatureQueryOptionsqueryOptions=newMgFeatureQueryOptions();

queryOptions.SetFilter("PARCELTYPE='MFG'");

queryOptions.SetSpatialFilter('SHPGEOM',bufferGeometry,

MgFeatureSpatialOperations.Inside);

MgResourceIdentifierfeatureResId=newMgResourceIdentifier(

"Library://Data/Parcels.FeatureSource");

MgFeatureReaderfeatureReader=

layer.SelectFeatures(queryOptions);


Documents

AutoCAD Map 3D 2009 Geospatial Platform … Up Visual Studio To use the Geospatial Platform API, follow the instructions in the AutoCAD Map 3D ObjectARX .NET Developer’s Guide. Add