We present a method to represent multi-resolution vector graphics such as road networks or railway networks in virtual environment. These vector data can be interactively edited and the landscape and be explored in re...We present a method to represent multi-resolution vector graphics such as road networks or railway networks in virtual environment. These vector data can be interactively edited and the landscape and be explored in real time at any altitude from flight view to car view. We design a context-focused vector description of linear can areal features, with associated customized definition painter to specify their appearance （color and material） and their display mode （detailed mode or simplified mode）. There are some special problems in drawing vector graphics in virtual environment. Floating-point round-off error appear when we use a low view point to observe the scene, and it leads to scene jittering. Drawing 3D wide lines turns into a problem on 3D terrain. We design a view-based self-adaptive interpolation algorithm and an offset line generating algorithm to solve it. Our results show high performance with good visual quality.展开更多
Because the existing vector data watermarking algorithm is insufficiently robust for compression and cropping,and has no sufficient control on map deformation,a new watermarking algorithm was proposed in this paper.It...Because the existing vector data watermarking algorithm is insufficiently robust for compression and cropping,and has no sufficient control on map deformation,a new watermarking algorithm was proposed in this paper.Its main features are：① it selected feature points and non-feature points from the sequence of Douglas,and then embedded watermarking points by wavelet transform,which is based on layer segmentation;② it enhanced the map deformation control design.Furthermore,it increased the map graphic deformation control design.The algorithm was applied to experimental data,and the test results showed that the algorithm had good robustness on graphics geometric transformation,the addition,deletion and cropping of points in graph layers.Also,the graph distortion had been well controlled.展开更多
Recent development and recognition methods of raster to vector conversion for engineering drawings are presented. The advantages and disadvantages of all existing models are analyzed. Some research challenges and futu...Recent development and recognition methods of raster to vector conversion for engineering drawings are presented. The advantages and disadvantages of all existing models are analyzed. Some research challenges and future directions are discussed.展开更多
The web of meso-scale meteorological observational station based on WebGIS realized by SVG technology was briefly introduced.Through grasping and applying SVG technology,the high-density automatic observational statio...The web of meso-scale meteorological observational station based on WebGIS realized by SVG technology was briefly introduced.Through grasping and applying SVG technology,the high-density automatic observational station in Anhui Province was developed.The web of meso-scale meteorological observational stations constructed by SVG technique can display the network graphics of weather data and intuitionistic vector graphics interface.展开更多
基金Supported by National Basic Research Program of China (973 Program,No.2010CB328002)National Natural Science Foundation of China (Nos.61232014,61121002,61173080)National Key Technology Research and Development Program of China (No.2013BAK03B07)
文摘We present a method to represent multi-resolution vector graphics such as road networks or railway networks in virtual environment. These vector data can be interactively edited and the landscape and be explored in real time at any altitude from flight view to car view. We design a context-focused vector description of linear can areal features, with associated customized definition painter to specify their appearance （color and material） and their display mode （detailed mode or simplified mode）. There are some special problems in drawing vector graphics in virtual environment. Floating-point round-off error appear when we use a low view point to observe the scene, and it leads to scene jittering. Drawing 3D wide lines turns into a problem on 3D terrain. We design a view-based self-adaptive interpolation algorithm and an offset line generating algorithm to solve it. Our results show high performance with good visual quality.
基金Supported by the National Natural Science Foundation of China (40401038)
文摘Because the existing vector data watermarking algorithm is insufficiently robust for compression and cropping,and has no sufficient control on map deformation,a new watermarking algorithm was proposed in this paper.Its main features are：① it selected feature points and non-feature points from the sequence of Douglas,and then embedded watermarking points by wavelet transform,which is based on layer segmentation;② it enhanced the map deformation control design.Furthermore,it increased the map graphic deformation control design.The algorithm was applied to experimental data,and the test results showed that the algorithm had good robustness on graphics geometric transformation,the addition,deletion and cropping of points in graph layers.Also,the graph distortion had been well controlled.
文摘Recent development and recognition methods of raster to vector conversion for engineering drawings are presented. The advantages and disadvantages of all existing models are analyzed. Some research challenges and future directions are discussed.
基金Supported by Anhui Meteorological Observatory Projects " Integration Design of Station Meteorological Observation Operation"
文摘The web of meso-scale meteorological observational station based on WebGIS realized by SVG technology was briefly introduced.Through grasping and applying SVG technology,the high-density automatic observational station in Anhui Province was developed.The web of meso-scale meteorological observational stations constructed by SVG technique can display the network graphics of weather data and intuitionistic vector graphics interface.
