1、虚拟现实英文版 Virtual reality technology The main content I OverviewII VR hardware and interaction devicesIII Virtual Reality and GIS networkIV Virtual reality technology develops V virtual environment modeling and tools VI development example:Virtual Campus Xianlin Campus of Nanjing Normal UniversityVII
2、Prospects and ProblemsAppendix:ReferencesI Outline Virtual reality is the development of computer technology is highly crystalline and is reflected in the various fields in the application process,including not only graphics,image processing,pattern recognition,network technology,parallel processing
3、 technology,artificial intelligence and other high-performance computing technology,but also involves mathematics,physics,communications,and even related to meteorology,geography,aesthetics,psychology and sociology.I-I What is virtual realityVirtual reality or virtual environment is generated by a c
4、omputer having spot feeling environment,it is a new interactive system.Virtual reality technology is essentially a highly realistic simulation of human vision in real life.Hearing.Action and other acts of interactive technology.Traditional information processing environment has been a people adapt c
5、omputer,while todays goal or idea is to gradually make computer adaptation and people called for the adoption of sight,hearing,touch,smell,and body,gesture or password,to participate in the information environmental treated to thereby obtain an immersive experience.This information processing system
6、 is no longer based on the one-dimensional digital space,but on a multidimensional information space.Virtual reality technology is a key technology to support this multi-dimensional information space.I-II Virtual Reality FeatursImmersionInteraction ImaginationImmersionImmersion vAn artificial comput
7、er generated virtual environment,this virtual environment is a three-dimensional digital models constructed by computer graphics,programmed into a computer to produce realistic virtual environment,allowing users to generate an immersive virtual environment visually the feeling,which is a sense of vi
8、rtual reality technology immersion(Immersion)or spot a sense of participationInteractionInteractionModel and the traditional three-dimensional animation and virtual reality are usually generated by CAD systems is not the same,it is not a static world,but an open,interactive,virtual reality environme
9、nt can influence by controlling and monitoring devices or users Effects,which is the second feature VR,i.e.interaction(Interaction).ImaginationImaginationVirtual reality is not just a demonstration of media,but also a design tool.It reflects the visual form designer ideas,such as when the front cove
10、r of a modern building,the first thing you do is for the buildings structure,beautiful idea to do detailed,in order to make quantitative,you need to many design drawings,of course,these drawings only insiders understand,virtual reality can put this idea into a visible virtual objects and environment
11、s,so that in the past only with traditional sand table design patterns upgrade to digital-per-view income that is perfection,greatly improving the quality and efficiency of the design and planning.This is the third category of VR has features that imagination(Imagination).I-III Virtual Reality class
12、ificaionDesktop Virtual RealityImmersive virtual realityAugmented Reality of Virtual RealityDistributed Virtual RealityI-IV IV The difference between virtual reality and three-dimensional animation Virtual Reality Three-dimensional animation A combination of digital virtual environment model based o
13、n real data from strict compliance with the standards and requirements of the project design,a scientific simulation systems.?Manipulator experience the virtual three-dimensional space,immersive.Of scenes painted directly by the animators made according to the material or imagined together,and real
14、environments and data have a big gap,belonging to demonstrate class works of art.?Presupposed observation path can not be changed.The operator can feel the movement to bring real-time scene changes,walking scene,and personally arranged the scene,with two-way interactive features.Only one-way present
15、ations as movie scene change,making the screen requires prior generation,time-consuming,laborious and costly.Virtual RealityThree-dimensional animationSupports stereoscopic display and 3D stereo,three-dimensional reality.Does not supportNo time limit,can show a true and detailed,and you can export f
16、iles in virtual reality animated video based on the same data can be used for the production of multi-mode body and publicity,cost-effective.Animation by the time limit,can not be detailed display,low price.In real-time three-dimensional environment,adjustment support programs,assessment,management,
17、information inquiry and other functions,suitable for larger complex project planning,design,bidding,approval,management and other needs,but also has a more realistic and intuitive multimedia presentation capabilities.Only suitable for simple presentation capabilities.I-V I-V Virtual reality technolo
18、gy used in the real worldMany game makers,in order to make the game more realistic character movements,often will use the motion capture system.Virtual reality technology use in the film.Example:MatrixDisplay of goods(such as home,appliances,etc.)II II VR hardware and interaction devicesA typical sy
19、stem consists of virtual reality space data acquisition system,the human data capture systems,three-dimensional display device,as well as three-dimensional control equipment and a computer system.Spatial data acquisition system,human data capture system in a virtual environment to establish space mo
20、del;3D display device,a three-dimensional control equipment belong to the same three-dimensional interactive equipment,design and manufacture of 3D interactive device superior performance is the key to virtual reality technology.Spatial Data Acquisition SystemHuman data capture systemComputer System
21、sSuper graphics workstationsThree-dimensional control equipment3D display deviceCollectionAlternatelySpatial Data Acquisition SystemSpatial data acquisition system to obtain timely spatial data through satellite remote sensing,aerial remote sensing and global positioning systems,and establishing an
22、accurate and reliable virtual reality space environment.Remote sensing is an advantage of the inherent characteristics of electromagnetic radiation reflected from an object and through implementation of electromagnetic waves,there are technical environmental conditions and object recognition object.
23、Human data capture systemHuman data capture device that can record the body of practical data and actions,including the body movements,facial expressions,physiological index,smell and voice.Interactive 3D EquipmentCommon 3D display device and stereoscopic helmet mounted display glasses.Helmet mounte
24、d display with three-dimensional drawing techniques to produce two spaced apart perspective,and directly displayed to the user corresponds to the left and the right eye on two monitors.The new helmet-mounted displays are accompanied by magnetic position sensor,can measure the direction of the users
25、line of sight,so the scene can change as the users line of sight and make the appropriate changes.Interactive 3D EquipmentA common feature of the three-dimensional space control device is capable of controlling at least six degrees of freedom(Degree of Freedom),corresponding to the three-dimensional
26、 object describing the width,height,depth,pitch(pitch)angle,rotation(yaw)angle and yaw(roll)angle.Common three-dimensional control device has data gloves,track ball,three-dimensional probe,three-dimensional and three-dimensional mouse control lever and the like.The emergence of the data glove,virtua
27、l reality system provides a new interactive tool that can provide users with a very real and natural three-dimensional interactive tools.High-performance computer systemsHigh-performance computer system processing technology includes data conversion and data preprocessing technologies;real-time,real
28、istic graphics image generation and display technology;multidimensional information data fusion,data compression,and generate the database;multiple sound synthesis and sound space technology;including command recognition,voice recognition,and detect gestures and facial expressions of information,inc
29、luding a pattern recognition;distributed and parallel computing,and high-speed,large-scale remote network technology.III III Virtual reality and networks,GIS Virtual reality technology now combines the latest research results in various disciplines,including the results of computer science,communica
30、tion network technology,geographic information systems,remote sensing science and other areas.The main contents of this section:Virtual GISNetwork Virtual GISDistributed GISGeographical synergyIII-I III-I Virtual GISDevelopment of computer science and human-computer interface technology in graphics,
31、especially the promotion of virtual reality technology for GIS provides a new analysis geoscience data and technology platform to explore issues,and promote the GIS technology with virtual reality technology and visualization fusion technology,expanding the multi-dimensional GIS,three-dimensional GI
32、S in particular connotation study provides new spatial data analysis models and new GIS application mode.Current international call this virtual reality technology and scientific visualization technology designed multidimensional GIS system called Virtual GIS system Virtual GIS(VGIS).III-II III-II N
33、etwork Virtual GIS presentationCombined with the current direction of the virtual network is a GIS development.Combined with network technology,network virtual GIS not only for people to analyze spatial data and spatial problem solving network provided by the technology platform,through immersive vi
34、rtual reality model for people to interact through virtual geospatial offers the possibility,thereby for the study of virtual geographical environment provides an ideal platform.Network Virtual GIS architecture1.A GIS is a virtual network-based GIS,virtual reality system with the GIS Client-linking
35、provides a simple spatial analysis or to analyze the results of GIS into virtual reality system to support virtual reality system data format,for virtual reality systems to observe;2.Another virtual GIS is based on a distributed virtual reality system,extend the ability to support spatial data types
36、 in a virtual reality system,providing simple spatial analysis.The overall structure of WEB virtual GISIII-IIIIII-III GIS system architectures role in the network virtual 3.3 CORBACORBA is one of the mainstream computing platform for distributed objects,CORBA platform to become widely accepted by th
37、e computer industry,and is fully open to the distributed network platform.CORBA is a distributed object-based design having scalability,security,load balancing and fault tolerance,real-time,special performance requirements for the design of distributed systems provide a rational platform.CORBA-based
38、 network platform to design virtual GIS,by reusing the CORBA network structure and basic network services greatly simplify virtual difficulty GIS network architecture design based on virtual GIS CORBA allows the network to use more flexible network architecture.CORBA-based naming service network VGI
39、S system image concept map-Network Virtual GIS client Application Server Name ManagementApplication server 1 Application server 2 Application server n Analysis Server Name ManagementSpatial Analysis Services 1 Spatial Analysis Services 2 Spatial analysis services nIII-IV III-IV VGE and geographic sy
40、nergiesVirtual Geographic Environments,is an avatar-based multi-user distributed intelligent three-dimensional virtual environment,a digital geo-spatial phenomena and laws of a particular geographical environment with multi-channel-aware expression,calculation and simulation,integrated management of
41、 the Earth can be used for multi-dimensional information and multimedia integrated publishing,interactive/innovative blend of style earth science research,and other distributed collaborative planning,design and decision-making.User avatarIn the virtual geographic environments,both user avatar can co
42、mmunicate face to face in the same virtual location.The incarnation as an expression of real users,and its source can contain visual,auditory and even taste a variety of information sources,etc.,so that the user has a sense of immersion can be immersive feel itself is a virtual geographic environmen
43、ts part.Seeing and hearing other information sources may be co-workers to communicate what the real attitudes and emotions,is an important part of communication between co-workers in virtual geographic environments,and analysis of geographic data in planning and decision-making also plays a very imp
44、ortant effect.AC ModeFor virtual geographic environment is not only a real geographical background,but also to provide a reliable platform for the exchange of information co-workers are.To this end,we need more research on how to improve communication modes between people and enhance various exchang
45、es avatar in virtual geographic environments between.Currently,in accordance with the timeliness of the exchange of classified-o Non-real-time communication:e-mail and bulletin boardo Instant communication:interactive,real-time,including the traditional two-dimensional scenes,three-dimensional scene
46、,streaming media technology and integration mode.IV IV The main development of virtual reality technologyVRMLXMLX3DJava3DVRMLXML地理实体地理实体JAVA3DIn the virtual reality technology,VRML/GeoVRML,XML,X3D,GML and Java3D technology strengths complement each other,the use of graphical modeling capabilities VR
47、ML,XML internationalization,structured,modular features and powerful Java network programming language,together form a powerful virtual reality environments.IV-I IV-I VRMLIn 1994,the first session of the International Internet Conference in Geneva,Switzerland,proposed to create a three-dimensional n
48、etwork interface to facilitate network transmission VRML.In 1995,VRML1.0 version launched.In 1996,based on the 1.0 version of the major improvements introduced in version 2.0,which adds interactive scenarios,multimedia support,collision detection.In 1997,after an assessment standards organizations,V
49、RML2.0 become the international standard,and renamed the VRML97.VRML simple examplesphere.wrl#VRML V2.0 utf8Shape#Define node contains two properties appearance Appearance#Appearance properties material Material#material，emissiveColor 1 0 0#Reflective material geometry Sphere#Geometric properties ra
50、dius 1IV-II IV-II XMLXML XML full name in English is Extensible Markup Language,the Chinese translation for extensible markup language.It is an exchange standard by the W3C(World Wide Web Consortium)the promotion of structured information,and has been widely used.VRML adopt XML as the encoding of th
