Research On Dam Perspective Projection And Visualization Drawing

Research on dam perspective projection and its visualization drawing attaches importance to the hydraulic digitalization and modernizes the design of hydraulic projects. It is concerned with reasonable development of water sources, and projects being built are to control flood and deduce catastrophes, even to conduct the effective management. This study aims to settle the urgent problems in the aspect of new angle of numerical calculation and perspective projection, including the correct location of dam toe line and excavation line, the visualized auxiliary design of dam plane, and the display of dam three-dimensional perspective drawing etc.. In addition, it sets up relatively complete and simple dam perspective projection and visualized methods. Main contents and results are as follows:(1)To evaluate dam toe line is of vital importance in dam computer auxiliary design, however, its evaluation traditionally adopts graphic solution. Its complexity, time-consuming and inaccuracy of the traditional drawing methods limit the automation and integration of computer auxiliary design. In order to solve them, it puts forwards the dam perspective research based on numerical solution. That is, on the basis of ground data and dam design data, the best way is to build mathematic model to judge the intersection points, the special points on the elevation toe line and convergence, etc.. Based on this numerical solution of the dam toe line, this paper studies and develops design system of dam plane visualization drawing to realize dam toe line solution and its visualization of automation and integration. Also based on the variation parameter, the function of reciprocal parameter drive to inquire display at any time was abtained. Besides, it completely realizes automatic solution and visualized drawing which changes the traditional shortcoming of hand drawing. A simple method which is feasible for such kinds of problem is offered to settle dam design of how to locate toe line, dam plan design and construction layout.(2) As to the need of great quantity of medium-small sized hydraulic projects, a new dam three-dimensional model constructing method is given, which adopts points to describe the topography and dam, and points that the data changes of topography and ground is the change of the points. It also applies elevation projection and perspective projection to build the perspective data mathematical model of vector data, analysis situsrelationships between point and point, then to adopt the three-dimensional perspective mathematic model of dam and topography and then to employ programme and automatic display technology of the drawing to develop dam three-dimensional perspective visualization software. At the same time, take dam rockfill as example, it studies the choice of dam and plan to conclude the correspondent drawing display results which is tight in theory and high in practice to generate three-dimensional dam perspective in multi-vision conditions. Apart from it, this method has the characteristic of high speed, convenience and economical etc., which doesn't need the support of other commercial software of the common computer. And to those of medium-small sized hydraulic project designs, choices of plan and its analyses are economical and suitable.(3) To utilize overlapping point location method and co-altitude points (distance and vicinity) settles the blanking problems of ground objects and topography perspective drawing. This paper changes the location of hidden line into the location of hidden points, changing blanking problems into the distance-and-vicinity between space point and visional point, and building the visible mathematical expression. To blank those of hill, mountain ridge or the swelling topography, it offers the discriminant to build the mathematic model of co-altitude points and offers the similar discriminant of co-altitude hidden-and-display.According to this blanking method by computer with the examples of dam and deck rockfill, it generates different directions, different angle dam three-dimensional perspective drawings which are correct in theory, and simple, direct and easy to realize. Comparatively, it avoids complex design shortcomings to speed up drawing and to improve to settle practical problems of mathematic model and provides a new means to blank perspective projection of topography and ground objects.(4) Similarly, this paper studies the generation method of dam perspective rendering which solves the organization and management of space foundation data. It builds a tri-angle net in accordance with the best angles to utilize the coordinate to locate the searching range, utilizing inclination angle to locate the tri-angle starting and ending directions, and defining its surrounding to proceed the second search which is simple and fast. In addition, it studies integrated technology of system design to build a centrally functional design, among three types of topography tri-angle net, dam quadrangle and system integrated control, to settle the complex data, demanding data store and data reading. The accomplishments of this paper can solve numerous sorts of drawing modelsof three-dimensional patterns, complex drawing of function programme, difficult three-dimensional perspective man and computer's reciprocity vagile and multi-angle observing programme design, etc.. Exclusively, it vividly and directly describes the effectiveness of the dam design to offer new method and technology for medium-small sized dam projects.In the last, having made the summary of the whole paper and brought up some expectations concerning the researches in the paper.