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Keyhole Markup Language (KML) definition


Keyhole Markup Language (KML) is an XML-based markup language designed to annotate and overlay visualizatio on various two-dimeional, Web-based online maps or three-dimeional Earth browse (such as Google Earth). In fact, KML was initially developed for use with Google Earth; because that project was originally named Keyhole, as was the company that undertook this work, the related markup language followed suit. When Google acquired Keyhole in 2004, that project came with it and eventually became Google Earth. The /keyhole/ moniker is a reference to the original KH military reconnaissance satellites fit launched in the mid-1970s that took the very fit /eye-in-the-sky/ photographs so commonly viewed within Google Earth and other geobrowse.
A KML file includes specificatio for various features for display within Google Earth, Maps and Mobile, and other three-dimeional Earth or geobrowser programs. KML's feature set includes placemarks, 3D models, text descriptio, images, polygo, and so forth. Each location has an associated longitude and latitude and view-specific data such as heading, altitude and tilt may be provided to define a so-called /camera view/ for geospatial data. KML shares some of its grammar with the geography markup language, or GML, an Open XML markup language defined to express geographical data and features.
The current specification for KML is 2.2, which has been submitted to the Open Geospatial Coortium (OGC) for ratification as an open standard that any geobrowser may use. Because the OGC already has custody over GML, this makes a good fit. KML documents are often distributed in the form of KMZ files, which are nothing more than a zipped KML document iide a file with a .kmz exteion. A KMZ file usually contai a single KML document, invariably named /doc.kml/ along with images for overlays and ico it may reference internally.


A specificatio for高层领导”的字眼自由通航一致维护两for地图和谷歌地球、移动和其他geobrowser查验。three-dimeional Earth黄金KML的特性集包括placemark对象、3 d模型,,文字说明一下好图片,polygo,等等。每个位置都有一个关联的经度和纬度和视图相关数据,如标题,高度和倾斜可能提供了定义一个所谓的相机视图/地理空间数据。KML股票与地理标记语言,它的一些语法或GML,开放的XML标记语言定义表达地理数据和特性。
当前规范KML是2.2,已提交开放地理空间Coortium(OGC)批准成为一个开放的标准,任何geobrowser可能使用。因为OGC已经GML抚养权,这使得一个不错的选择。往往因KML documents in the form of distributed KMZ files are more than中,无论在zipped KML document空间在file with a。exteion kmz。在一个contai KMZ file一KML document,总是叫/医生。kml /连同图片覆盖和ico内部参考。

最近更新时间:2015-11-30 EN