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
The study of marine data visualization is of great value. Marine data, due to its large scale, random variation and multiresolution in nature, are hard to be visualized and analyzed. Nowadays, constructing an ocean mo...The study of marine data visualization is of great value. Marine data, due to its large scale, random variation and multiresolution in nature, are hard to be visualized and analyzed. Nowadays, constructing an ocean model and visualizing model results have become some of the most important research topics of ‘Digital Ocean'. In this paper, a spherical ray casting method is developed to improve the traditional ray-casting algorithm and to make efficient use of GPUs. Aiming at the ocean current data, a 3D view-dependent line integral convolution method is used, in which the spatial frequency is adapted according to the distance from a camera. The study is based on a 3D virtual reality and visualization engine, namely the VV-Ocean. Some interactive operations are also provided to highlight the interesting structures and the characteristics of volumetric data. Finally, the marine data gathered in the East China Sea are displayed and analyzed. The results show that the method meets the requirements of real-time and interactive rendering.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 Natural Science Foundation of China under Project 41076115the Global Change Research Program of China under project 2012CB955603the Public Science and Technology Research Funds of the Ocean under project 201005019
文摘The study of marine data visualization is of great value. Marine data, due to its large scale, random variation and multiresolution in nature, are hard to be visualized and analyzed. Nowadays, constructing an ocean model and visualizing model results have become some of the most important research topics of ‘Digital Ocean'. In this paper, a spherical ray casting method is developed to improve the traditional ray-casting algorithm and to make efficient use of GPUs. Aiming at the ocean current data, a 3D view-dependent line integral convolution method is used, in which the spatial frequency is adapted according to the distance from a camera. The study is based on a 3D virtual reality and visualization engine, namely the VV-Ocean. Some interactive operations are also provided to highlight the interesting structures and the characteristics of volumetric data. Finally, the marine data gathered in the East China Sea are displayed and analyzed. The results show that the method meets the requirements of real-time and interactive rendering.
