Research And Implementation Of 3D Channel Terrain Visualization Based On OSG

With the rapid development of three-dimensional graphics processing, and the gradual maturation of three-dimensional visualization technology, three-dimensional simulation technology has been widely used in various fields. In the respect of channel regulation, people could not comprehensive grasp and analyses the information of channel terrain in the practical process of regulation. Due to the complex channel terrain, it is fully needed to consider the uncertainties which are the different channel basin slope, the features of channel terrain, the soil condition and land use status. It is affected the actual result of the channel regulation. However, the problem is solved by using three-dimensional emulation technology which could display the information of channel terrain information and comprehensive characteristics on information of channel terrain. It also could help the experts provide decision support of visualization simulation for making scientific scheme of channel terrain regulation. So the paper is studied on terrain model of three-dimensional channel based on channel regulation and using C++ and Open Scene Graph. It is realized visualization system of three-dimensional channel terrain based on OSG. The concrete contents are as follows:(1)The model building and the method of shading process on three-dimensional channel terrain is studied. According to the building theory of scene about OSG, the paper analyzes elevation data and studies the way of terrain generation on three-dimensional channel terrain and layered shading process on elevation data.(2)The method how to extract the shoulder line of valley and toe line as well as filling earthwork in the three-dimensional scene is given. The method is from two aspects:the extraction of shoulder line of valley and toe line; the equivalent calculation of slop, change rate of slop and partial slop?(3)The way how to draw and display the cross sections, to render the three-dimensional scene by using OSG is researched.(4)The visual system on the three-dimensional channel terrain is designed and implemented. According to these key technologies, the paper is studied the development of visual system about interactive three-dimensional terrain. It is realized the building three-dimensional channel terrain, layered coloring of elevation data, the extraction and display of shoulder line of valley and toe line, analysis the cross section and the calculation of excavation and filling.The results are showed that the visual system can more intuitive be displayed the three-dimensional information and comprehensive characteristics based on OSG. It has a well applied value and prospect on channel regulation and the development and utilization of land. It is also provided convenient, intuitive visualization applications for the exploitation and utilization of land.