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1、Open Source GIS and Dynamic Languages,Gao AngState Key Laboratory of Resources and Environmental Information SOSGeo ChinaJuly.2007,Agenda,Overview of OpenSource CommunityWhats FOSSWho use OSSFOSS LicensesIntroduction of OpenSource GISOpenSource GIS DesktopOpenSource Web GISFuture of OS GISApplicatio
2、n of Dynamic LanguageBrief intro of PythonWeb development with Django,What is Open Source Software (OSS)?,First and foremost, it is softwareJust like you can buy from vendorsJust like you can build for yourselfUses a licensing model that promotes collaborationGrants rights to useGrants rights to mod
3、ifyGrants rights to redistributeNot just “free” softwareZero licensing cost promotes adoption and collaboration but is not the purpose of OSSMost commonly associated with LinuxOther well-known projects are the Apache web server, the Mozilla Firefox browser, and OpenOffice.org office suite,Where does
4、 OSS come from?,Enterprises are large contributors (eg. IBM)Employ individual developersContribute codeParticipate in consortiaVendors are also deeply involved (eg. ThoughtWorks)Use OSS as a competitive weaponCollaborate with OSS projects to lower costsOffer OSS as an entry level product for other p
5、roductsParticipate in consortia to share development costs and build standards65% of all internet servers are based on open source software.1/3 of the worlds 25 largest software companies engage in OSS activities. (e.g. IBM have invested $1billion in Linux activities).,Why do people use OSS?,There i
6、s no single reason why you should use or get involved with OSS. Different groups are involved for different reasons. Benefits and risks are unique to your situation.DevelopersCarry skills from job to job; improving skills and learning best practices through peer reviewEnterprisesLower software licen
7、se costs Reduce vendor reliance; gain control by having more choicesHelp set/influence directionReduce riskSoftware vendorsLower overall solution cost; strategic moves against competitors; loss leader; support more hardwareHardware VendorsLower overall solution cost,Freedom of FOSS,Four basic freedo
8、ms (The Free Software Foundation)The freedom to run the program, for any purpose. The freedom to study how the program works, and adapt it to your needs. Access to the source code is a precondition for this. The freedom to redistribute copies so you can help your neighbor. The freedom to improve the
9、 program, and release your improvements to the public, so that the whole community benefits. Access to the source code is a precondition for this.,A Comparison of FOSS Licenses,GIS Desktop Software Stack,OS GIS Desktop Applications,GRASS GIS,Web GIS Software Stack,OS GIS - Server Tools,GRASS GIS,GDA
10、L/OGR,R-Statistics,Commercial vs. OpenSource,ArcReaderArcMap/ArcGISArcINFO/ArcGRIDArcPadArcSDEArcIMSArcGIS ServerVB, Python,UDig,Jump,GRASS,QGis,OSSIMUDig,Jump,GRASS,QGis,OSSIMGRASS, OSSIM?PostGISMapserverGRASSPHP, Python, Perl, C#.net, etc,Viewing,Cartography,Analysis,Devices,Database,Web,Spatial S
11、erver,Scripting,Comparison of OpenSource and Commercial,Example OSGIS in use,QGIS and GRASS as a desktop supplementQT as desktop application framework ( Google Earth)PostGIS to store vector data layersMapserver as a web-based front endChameleon Interface as a client side web interfaceGRASS as a serv
12、er side GIS for DST developmentOGR/GDAL to pre-process vector and raster dataR-Statistics and GMT for graphing and statistics,Example Paper Map Publishing,QGIS,ArcMap,GRASS GIS,Java GIS with Eclipse Rich Client Platform,OpenSource Python GIS Application,R-Statistics,Where is it all going?,Integratio
13、n of OS software across organizations“Google” type interfaces (smooth user experience)AJAX drivenStreaming mediaSeamless datasetsLarge datasets require more pre-processingPressure on large private companies to become more responsive to end user needsIntegration of OSGIS with proprietary software req
14、uired for migration pathStart of services based business,Google Maps,北纬39度54分27秒，东经116度23分17秒。经纬度转换为弧度，规格化在0到1区间。换算后得到北京中心的Google坐标字符串是trstrqqrqssttttrrrstq对应的卫星影像块地址则是：http:/ Web GIS Architecture,Making GIS analysis accessible and affordable via Internet,OSGeo in China,OpenSource Project of OSGeo,O
15、SGeo in China,Michael P. Gerlek deliver a speech for Chinese students,Wide Support for OpenSource GeoSpatial,Microsoft Windows,Linux,Apache Web Server,Microsoft IIS,OS,Server,Language,Browser,Internet Explorer,Mozilla Firefox,Safari,Section Dynamic Languages,Gao AngState Key Laboratory of Resources and Environmental Information SOSGeo ChinaJuly.2007,What is Python?,O-O rapid prototyping languageNot just a scripting languageNot just another PerlEasy to learn, read, useExtensible (add new modules)C/C+/Fortran/whateverJava (through Jython)Embeddable in applications,
