Terrain Visualization is an important part of visualization systems of battlefield,and the visualization of dynamic terrain is also important for dynamic battle environment.In this paper,special attention has been pai...Terrain Visualization is an important part of visualization systems of battlefield,and the visualization of dynamic terrain is also important for dynamic battle environment.In this paper,special attention has been paid on real-time optimally adapting meshes (ROAM) algorithm,which is a candidate for dynamic terrain,and its mesh representation,mesh continuity algorithm and error metrics are discussed.The DEXTER-ROAM algorithm is discussed and analyzed.By revising the mesh representation of ROAM,a dynamic ROAM algorithm based on partial-regular grid is established.By introducing transition region,mesh discontinuity of dynamic partial-regular grid is resolved.Error metric blocks are removed for computation complexity and culling blocks are introduced to accelerate view frustum culling.The algorithm is implemented in a 3D rendering engine called OGRE.In the end,an example of dynamic crater is given to examine the dynamic ROAM algorithm.展开更多
Incremental LOD can be transmitted on the network as a stream, then users on the clients can easily catch the skeleton of terrain without downloading all the data from the server. Detailed information in a local part ...Incremental LOD can be transmitted on the network as a stream, then users on the clients can easily catch the skeleton of terrain without downloading all the data from the server. Detailed information in a local part can be added gradually when users zoom it in without redundant data transmission in this procedure. To do this, an incremental LOD method is put forward according to the regular arrangement of grid. This method applies arbitrary sized grid terrains and is not restricted to square ones with a side measuring 2 k + 1 samples. Maximum height errors are recorded when the LOD is preprocessed and it can be visualized with the geometrical Mipmaps to reduce the screen error.展开更多
Study on 3D terrain visualization is a hot research topic in GIS, virtual reality, computer graphics, digital photogrammetry and other fields, is also an important part of the digital earth strategy. Try to take advan...Study on 3D terrain visualization is a hot research topic in GIS, virtual reality, computer graphics, digital photogrammetry and other fields, is also an important part of the digital earth strategy. Try to take advantage of IDL data processing and graphic display function and ArcEngine spatial analysis function, in the Visual c# under the environment of hybrid programming mechanism, use of component design and development of integrated development technologies analysis of terrain visualization application operating environment, realized the 3D digital terrain expression and spatial analysis function. The results show that the IDL and ArcEngine integrated development method applied to the 3D terrain visualization analysis software platform developed operability and extension force with strong, both in terms of space efficiency and image data analysis , development costs advantages.展开更多
3D terrain visualization of geographic information systems(GIS)data has become an important issue in recent years.This is due to the emergence of new geo-browsers such as Google Earth,widely popular among users.The av...3D terrain visualization of geographic information systems(GIS)data has become an important issue in recent years.This is due to the emergence of new geo-browsers such as Google Earth,widely popular among users.The availability of 3D representation tools has increased the demand for 3D terrain visualization.The aim of this paper is to review the literature related to the 3D terrain visualization of GIS data from the first map produced until the online mapping era.The reviews are divided into four different sections:manual visualization of 3D terrain,automated visualization of 3D terrain,online visualization of 3D terrain,and software for visualizing 3D terrain.Then,the paper compares between the different types of systems developed by various authors based on the capabilities and the limitations of the system.Some of the techniques have their own strengths and limitations which solve the problem in 3D terrain visualization.However,the research on improving 3D terrain visualization is still ongoing.This is due to the popularity of online environments and mobile devices that render 3D terrain.This review paper will help interested users understand the current state of 3D terrain visualization of GIS data in a better way.展开更多
Objective Aim to create a three-dimension（3D） reconstruction of acupuncture needling at Sidu（四渎 TE 9）.Methods First,the skin,subcutaneous tissue,muscles,the blood vessels and nerves near TE 9 were defined in ana...Objective Aim to create a three-dimension（3D） reconstruction of acupuncture needling at Sidu（四渎 TE 9）.Methods First,the skin,subcutaneous tissue,muscles,the blood vessels and nerves near TE 9 were defined in anatomical terms.Second,the above anatomical structures including the dissected muscles associated with at TE 9,the underlying blood vessels and nerves were reconstructed in 3D.Third,the process of acupuncturing TE 9 on a virtual human body was simulated using the VOXEL-MAN technology.Results Both the local anatomy of the point and the process of acupuncture needling at TE 9 were reconstructed.Different layers of tissues were visualized during the process of needling,as the needle was inserted and manipulated at the point.Conclusions Virtual 3D reconstruction can contribute to research on the anatomical structure of acupoints and the visualization of the acupoints.We recommend that it be fully utilized in acupuncture research.展开更多
文摘Terrain Visualization is an important part of visualization systems of battlefield,and the visualization of dynamic terrain is also important for dynamic battle environment.In this paper,special attention has been paid on real-time optimally adapting meshes (ROAM) algorithm,which is a candidate for dynamic terrain,and its mesh representation,mesh continuity algorithm and error metrics are discussed.The DEXTER-ROAM algorithm is discussed and analyzed.By revising the mesh representation of ROAM,a dynamic ROAM algorithm based on partial-regular grid is established.By introducing transition region,mesh discontinuity of dynamic partial-regular grid is resolved.Error metric blocks are removed for computation complexity and culling blocks are introduced to accelerate view frustum culling.The algorithm is implemented in a 3D rendering engine called OGRE.In the end,an example of dynamic crater is given to examine the dynamic ROAM algorithm.
文摘Incremental LOD can be transmitted on the network as a stream, then users on the clients can easily catch the skeleton of terrain without downloading all the data from the server. Detailed information in a local part can be added gradually when users zoom it in without redundant data transmission in this procedure. To do this, an incremental LOD method is put forward according to the regular arrangement of grid. This method applies arbitrary sized grid terrains and is not restricted to square ones with a side measuring 2 k + 1 samples. Maximum height errors are recorded when the LOD is preprocessed and it can be visualized with the geometrical Mipmaps to reduce the screen error.
文摘Study on 3D terrain visualization is a hot research topic in GIS, virtual reality, computer graphics, digital photogrammetry and other fields, is also an important part of the digital earth strategy. Try to take advantage of IDL data processing and graphic display function and ArcEngine spatial analysis function, in the Visual c# under the environment of hybrid programming mechanism, use of component design and development of integrated development technologies analysis of terrain visualization application operating environment, realized the 3D digital terrain expression and spatial analysis function. The results show that the IDL and ArcEngine integrated development method applied to the 3D terrain visualization analysis software platform developed operability and extension force with strong, both in terms of space efficiency and image data analysis , development costs advantages.
文摘3D terrain visualization of geographic information systems(GIS)data has become an important issue in recent years.This is due to the emergence of new geo-browsers such as Google Earth,widely popular among users.The availability of 3D representation tools has increased the demand for 3D terrain visualization.The aim of this paper is to review the literature related to the 3D terrain visualization of GIS data from the first map produced until the online mapping era.The reviews are divided into four different sections:manual visualization of 3D terrain,automated visualization of 3D terrain,online visualization of 3D terrain,and software for visualizing 3D terrain.Then,the paper compares between the different types of systems developed by various authors based on the capabilities and the limitations of the system.Some of the techniques have their own strengths and limitations which solve the problem in 3D terrain visualization.However,the research on improving 3D terrain visualization is still ongoing.This is due to the popularity of online environments and mobile devices that render 3D terrain.This review paper will help interested users understand the current state of 3D terrain visualization of GIS data in a better way.
基金Science and Technology Development Fund projects for Higher college of Tianjin City:20110218Doctoral Program of the Higher Education Specialized Research Fund for New Teachers:20121210120007+1 种基金Teaching Reform Project of Tianjin University of Traditional Chinese Medicine:2013JYL025National Basic Research Program of China:2014 CB 54320x
文摘Objective Aim to create a three-dimension（3D） reconstruction of acupuncture needling at Sidu（四渎 TE 9）.Methods First,the skin,subcutaneous tissue,muscles,the blood vessels and nerves near TE 9 were defined in anatomical terms.Second,the above anatomical structures including the dissected muscles associated with at TE 9,the underlying blood vessels and nerves were reconstructed in 3D.Third,the process of acupuncturing TE 9 on a virtual human body was simulated using the VOXEL-MAN technology.Results Both the local anatomy of the point and the process of acupuncture needling at TE 9 were reconstructed.Different layers of tissues were visualized during the process of needling,as the needle was inserted and manipulated at the point.Conclusions Virtual 3D reconstruction can contribute to research on the anatomical structure of acupoints and the visualization of the acupoints.We recommend that it be fully utilized in acupuncture research.
