.4 D Integrated Digital Electronic Atlas Of Key Technology Research And Implementation

Digital maps have the advantages of converting general maps into new maps conveniently by combing and matching any elements of general maps freely. Furthermore, new maps can be produced with any measuring scale and arbitrary scope. Based on the field investigation to the surface feature and landforms of Bajiazui Reservoir, firstly, the thesis puts forward the development of 4D digital model maps, and then it finishes 4D digital maps of the reservoir by adopting the 4D digital maps construction theories and methods. The research findings is quite valuable to the study of hydrology and current conditions, water flow, polluted area, the amount of mud and sand, waters area and so on..First, the thesis presents a detailed analysis on the collected data of the reservoir and its surrounding area, then it aims at solving the techincal problems by analysing the store model of classified subject for 4D digital maps and framing study for the 4D digital maps, the data structure of the vectors and the study of coordinate conversion algorithm. In order to solove the partial difficulties, the study adopts the method "from the bottom to the top "engineering analysis method, whereas it adopts the method of "from the top to the bottom" to solve the overall difficulties, it contructs the physical model for overall structure and bottom data, and other kinds of expandable models are considered while the frame is constructed, at the same time, the solution to the current problem is expanded to any subject., and enough space is saved for functional expansion, and the combination of Direct X and 4D digital maps can be achieved when the algorithm study is high-developed.The system adpots Visual Basic 6.0 as its development tool and SQL SERVER2000 as the data background, and in order to display the 3D image on the screen easily it writes the program by using Direct X, it not only simplifies the program-writing, but also improves the performance.The test result shows the conclusion drawn from the system data meets the factual condition and reponses quickly, it is accurate and applicable, easy to operate.