Pipelines are an important part of urban infrastructure development.As part of a virtual globe(VG),the high-efficiency and high-quality visualization of 3D large-scale and high-density urban pipelines is of great impo...Pipelines are an important part of urban infrastructure development.As part of a virtual globe(VG),the high-efficiency and high-quality visualization of 3D large-scale and high-density urban pipelines is of great importance.This paper proposes a GPU-based pipeline ray casting method for the visualization of urban-scale pipelines in the framework of a VG.The method involves the initial partitioning of the pipeline data into tiles,based on the relationship between the pipeline layer scale and the discrete global grid system(DGGSs).The pipeline centerline in each tile is then segmented and encoded,and a coarser pipeline bounding volume is subsequently constructed using a geometry shader.Finally,the fine 3D pipeline is rendered using a pixel shader.The results of the experimental implementation of the proposed method show that it satisfies the requirements for the multiscale visualization of pipelines in a VG.Moreover,compared with the traditional polygon-based method,the method facilitates a 20%increase in rendering frame rate for the same pixel level accuracy display effect.It also enables the visualization of the thickness of the 3D pipeline without any obvious effect on the rendering efficiency。展开更多
In this paper,we present a novel ocean visualization framework,which focuses on analyzing multidimensional and spatiotemporal ocean data.GPU-based visualization methods are explored to effectively visualize ocean data...In this paper,we present a novel ocean visualization framework,which focuses on analyzing multidimensional and spatiotemporal ocean data.GPU-based visualization methods are explored to effectively visualize ocean data.An improved ray casting algorithm for heterogeneous multisection ocean volume data is presented.A two-layer spherical shell is taken as the ocean data proxy geometry,which enables oceanographers to obtain a real geographic background based on global terrain.An efficient ray sampling technique including an adaptive sampling technique and a preintegrated transfer function is proposed to achieve high-effectiveness and high-efficiency rendering.Moreover,an interactive transfer function is also designed to analyze the 3D structure of ocean temperature and salinity anomaly phenomena.Based on the framework,an integrated visualization system called i4Ocean is created.The visualization of ocean temperature and salinity anomalies extracted interactively by the transfer function is demonstrated.展开更多
文摘Pipelines are an important part of urban infrastructure development.As part of a virtual globe(VG),the high-efficiency and high-quality visualization of 3D large-scale and high-density urban pipelines is of great importance.This paper proposes a GPU-based pipeline ray casting method for the visualization of urban-scale pipelines in the framework of a VG.The method involves the initial partitioning of the pipeline data into tiles,based on the relationship between the pipeline layer scale and the discrete global grid system(DGGSs).The pipeline centerline in each tile is then segmented and encoded,and a coarser pipeline bounding volume is subsequently constructed using a geometry shader.Finally,the fine 3D pipeline is rendered using a pixel shader.The results of the experimental implementation of the proposed method show that it satisfies the requirements for the multiscale visualization of pipelines in a VG.Moreover,compared with the traditional polygon-based method,the method facilitates a 20%increase in rendering frame rate for the same pixel level accuracy display effect.It also enables the visualization of the thickness of the 3D pipeline without any obvious effect on the rendering efficiency。
基金supported by the National Natural Science Foundation of China[grant number 42030406]the Marine Science&Technology Fund of Shandong Province for Pilot National Laboratory for Marine Science and Technology(Qingdao)[grant number 2018SDKJ0102]+2 种基金the National Key R&D Program of China[grant number 2016YFC1401008]the ESA-NRSCC Scientific Cooperation Project on Earth Observation Science and Applications:Dragon 5[grant number 58393]the Open Fund of Key Laboratory of Urban Land Resources Monitoring and Simulation,Ministry of Natural Resources[grant number KF-2020-05-085].
文摘In this paper,we present a novel ocean visualization framework,which focuses on analyzing multidimensional and spatiotemporal ocean data.GPU-based visualization methods are explored to effectively visualize ocean data.An improved ray casting algorithm for heterogeneous multisection ocean volume data is presented.A two-layer spherical shell is taken as the ocean data proxy geometry,which enables oceanographers to obtain a real geographic background based on global terrain.An efficient ray sampling technique including an adaptive sampling technique and a preintegrated transfer function is proposed to achieve high-effectiveness and high-efficiency rendering.Moreover,an interactive transfer function is also designed to analyze the 3D structure of ocean temperature and salinity anomaly phenomena.Based on the framework,an integrated visualization system called i4Ocean is created.The visualization of ocean temperature and salinity anomalies extracted interactively by the transfer function is demonstrated.