简介:Thispaperpresentsacomponentobjectmodel(COM)basedframeworkformanaging,analyzingandvisualizingmassivemulti-scaledigitalelevationmodels(DEMs).Theframeworkconsistsofadatamanagementcomponent(DMC),whichisbasedonRDBMS/ORDBMS,adataanalysiscomponent(DAC)andadatarendercomponent(DRC).DMCcanmanagemassivemulti-scaledataexpressedatvariousreferenceframeswithinapyramiddatabaseandcansupportfastaccesstodataatvariableresolution.DACintegratesmanyusefulappliedanalyticfunctionswhoseresuitscanbeoverlaidwiththe3DscenerenderedbyDRC.DRCprovidesviewdependentdatapagingwiththesupportoftheunderlyingDMCandorganizesthepotentialvisibledataatdifferentlevelsintorendering.