【英文标准名称】:Informationtechnology-Computergraphicsandimageprocessing-TheVirtualRealityModelingLanguage-Part1:FunctionalspecificationandUTF-8encoding
【原文标准名称】:信息技术.计算机制图和成像处理.虚拟现实模拟语言.第1部分:功能规范和UTF-8编码
【标准号】:ISO/IEC14772-1-1997
【标准状态】:现行
【国别】:国际
【发布日期】:1997-12
【实施或试行日期】:
【发布单位】:国际标准化组织(IX-ISO)
【起草单位】:ISO/IECJTC1
【标准类型】:()
【标准水平】:()
【中文主题词】:3D图;信息技术;计算机制图;计算机软件;成像处理;人工语言;数据处理;定义;多媒体;超媒体;式样
【英文主题词】:Artificiallanguages;Computergraphics;Computersoftware;Dataprocessing;Definition;Definitions;Hypermedia;Imageprocessing;Informationtechnology;Multimedia;Patterns;3D-graphic
【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】:236P.;A4
【正文语种】:英语