【英文标准名称】:Informationtechnology.Computergraphicsandimageprocessing.TheVirtualRealityModellingLanguage.FunctionalspecificationandUTF-8encoding
【原文标准名称】:信息技术.计算机制图学和图象处理.虚拟现实模拟语言.功能规格和UTF-8编码
【标准号】:BSISO/IEC14772-1-1998
【标准状态】:作废
【国别】:英国
【发布日期】:1998-12-15
【实施或试行日期】:1998-12-15
【发布单位】:英国标准学会(BSI)
【起草单位】:
【标准类型】:()
【标准水平】:()
【中文主题词】:多媒体;计算机软件;计算机制图;虚拟现实语言;英特网应用;编码(数据转换);计算机应用;高级语言;程序设计;程序设计语言;数据处理
【英文主题词】:high-levellanguages;programming;programminglanguages;computergraphics;computersoftware;internetapplications;virtualrealitylanguages;computerapplications;dataprocessing;multimedia;coding(dataconversion)
【摘要】:ISO/IEC14772,theVirtualRealityModelingLanguage(VRML),definesafileformatthatintegrates3Dgraphicsandmultimedia.Conceptually,eachVRMLfileisa3Dtime-basedspacethatcontainsgraphicandauralobjectsthatcanbedynamicallymodifiedthroughavarietyofmechanisms.ThispartofISO/IEC14772definesaprimarysetofobjectsandmechanismsthatencouragecomposition,encapsulation,andextension.ThesemanticsofVRMLdescribeanabstractfunctionalbehaviouroftime-based,interactive3D,multimediainformation.ISO/IEC14772doesnotdefinephysicaldevicesoranyotherimplementation-dependentconcepts(e.g.,screenresolutionandinputdevices).ISO/IEC14772isintendedforawidevarietyofdevicesandapplications,andprovideswidelatitudeininterpretationandimplementationofthefunctionality.Forexample,ISO/IEC14772doesnotassumetheexistenceofamouseor2Ddisplaydevice.EachVRMLfile:a.implicitlyestablishesaworldcoordinatespaceforallobjectsdefinedinthefile,aswellasallobjectsincludedbythefile;b.explicitlydefinesandcomposesasetof3Dandmultimediaobjects;c.canspecifyhyperlinkstootherfilesandapplications;d.candefineobjectbehaviours.AnimportantcharacteristicofVRMLfilesistheabilitytocomposefilestogetherthroughinclusionandtorelatefilestogetherthroughhyperlinking.Forexample,considerthefileearth.wrlwhichspecifiesaworldthatcontainsasphererepresentingtheearth.ThisfilemayalsocontainreferencestoavarietyofotherVRMLfilesrepresentingcitiesontheearth(e.g.,fileparis.wrl).Theenclosingfile,earth.wrl,definesthecoordinatesystemthatallthecitiesresidein.Eachcityfiledefinestheworldcoordinatesystemthatthecityresidesinbutthatbecomesalocalcoordinatesystemwhencontainedbytheearthfile.Hierarchicalfileinclusionenablesthecreationofarbitrarilylarge,dynamicworlds.Therefore,VRMLensuresthateachfileiscompletelydescribedbytheobjectscontainedwithinit.AnotheressentialcharacteristicofVRMListhatitisintendedtobeusedinadistributedenvironmentsuchastheWorldWideWeb.Therearevariousobjectsandmechanismsbuiltintothelanguagethatsupportmultipledistributedfiles,including:e.in-liningofotherVRMLfiles;f.hyperlinkingtootherfiles;g.usingestablishedInternetandISOstandardsforotherfileformats;h.definingacompactsyntax.
【中国标准分类号】:L81
【国际标准分类号】:35_060
【页数】:
【正文语种】:英语