Generating Techniques Of 3D Navigation Scene Based On Embedded System

With the development of city traffic and road-net, the development of navigation software enters a new era, and the navigation software which is based on 3D scene becomes a new research field and focus. Based on the application of 3D navigation, the thesis focuses on the generating techniques and methods of 3D navigation scene on embedded terminal with low frequency, small memory and low resolution, and realizes the display of 3D scene under the embedded circumstance. The main contents and contributions in this thesis can be summarized as follows:Firstly, on the bases of analyzing the constitution and content of 3D navigation scene, the expression and display methods of every element are discussed, which establishes the foundation for the build of navigation scene.Secondly, according to the distribution of elevation points to estimate the terrain undulation and warping, a self-adaptive multi-resolution DEM generation algorithm is presented, which effectively advances the DEM created speed.Thirdly, focusing on the low configuration of embedded device, a better adaptable data structure model is designed, and a method of combining file and embedded database SQlite is adopted to manage the scene data, which efficiently solves the problem of massive scene data organization and management under the embedded circumstance.Finally, adopting the patch strategy to simplify the scene data, an index of dynamic loading datas is designed. Through the methods of view frustum culling and multithreading technique, the speed of scene visualization has been effectively promoted.