Research On Multi-resolution Terrain Modeling Method Based On Viewpoint Motion And Prediction

With the development of remote sensing,geographic information and other technologies,high-precision terrain data can be obtained more conveniently and quickly,and the application of digital elevation models is becoming more and more extensive.Level of Detail(LOD)can reduce the amount of scene rendering data,significantly improve the rendering speed of complex scenes,maximize the quality of the picture and the rendering efficiency,and realize the dynamic real-time display of the scene,thus effectively simplifying the scene.Capabilities are widely used in terrain modeling.In order to improve the efficiency of large-scale terrain rendering,based on computer graphics,geographic information technology,visualization technology and virtual reality technology,the detailed level model and related technologies are studied in detail.The main research contents and results of this thesis are as follows:(1)A node evaluation function based on viewpoint motion is proposed,and the quadtree LOD model generation algorithm is improved.The improved method for motion error of quadtree based on multi-Resolution constraint,referred to as IMQBMR).The evaluation function combines terrain roughness,viewpoint distance and motion vector to guide the segmentation of terrain nodes.Experiments show that the I-MQBMR algorithm can achieve good terrain adaptive segmentation.When the viewpoint motion speed is increased,the terrain rendering complexity can be reduced,which improves the terrain rendering efficiency and improves the image frame rate.(2)A viewpoint prediction algorithm based on a dynamic step size(Viewpoint Prediction of Hermite Interpolation Algorithm Based on Dynamic Step Size,H-VPDSS)is proposed.By improving the Hermitian interpolation prediction algorithm,the dynamic change mechanism of the step size and the terrain data scheduling strategy are used to realize the pre-view data pre-fetching from the predicted viewpoint and the prediction.Experiments show that terrain rendering using the H-VPDSS algorithm has a more stable frame rate.(3)The experiment of slope,slope direction and section change of different viewpoint motion speeds is designed.With the change of viewpoint speed,the number of triangles in the terrain model is different,and the complexity of the terrain model changes at the same time.The slope,slope direction and profile follow The synchronization has changed.Experiments show that the I-MQBMR and H-VPDSS algorithms are effective and maintain good terrain realism.