Research On Three-dimensional Visualization Of The Cable Stayed Bridge

With the diverse models, complex structures and forms, a low degree of standardization of bridges, therefore, the three-dimensional modeling and visual simulation of a bridge are difficult. At present, the three-dimensional modeling of bridges is usually treated in AutoCAD or 3Dmax manually, but this method has the faults of fussy process, randomness, and is not conducive to accurate modeling. Once the models are formed, the.changes of geometry are more difficult. In order to overcome these deficiencies, making the bridge modeling universal, what this paper represents which bases on WINDOWS operation platform, using MFC of VC++ and OpenGL graphics library, combining the characteristics of Cable Stayed Bridge, adopting parameterized method for three-dimensional modeling of Cable Stayed Bridge, has developed three-dimensional visualization system of Cable Stayed Bridge. The study has very important practical significance for aided design, project selection of Cable Stayed Bridge and the coordinated effects evaluated between the bridges and surrounding environment when the bridges completed.This system has the following functions:(1) Developed with the specific characteristics of the Cable Stayed Bridge, the system can complete the 3-D visualization of several models of Cable Stayed Bridge, and also can be applied to most of the beam bridge.(2) Parameterized modeling method. Combining with the interactive graphics technology and OpenGL graphic library, the system can realize the parameterized modeling for main elements of Cable Stayed Bridge. And driving with changed parameters, the user can modify the designing results. Thought the Hierarchical Modeling, the whole three-dimensional models of Cable Stayed Bridge can be finished.(3) Realistic Cable Stayed Bridge. With texture mapping technology of OpenGL, the components of Cable Stayed Bridge are texture mapped and the surface details are simulated. An amount of time and energy can be saved by the method as details of modeling. At the meanwhile, the objectivity and three-dimensional effect of Cable Stayed Bridge under the light are strengthened.(4) With the surrounding terrain of Cable Stayed Bridge simulated, the system enhanced the three-dimensional visualization of Cable Stayed Bridge, and the effect of Cable Stayed Bridge also can be observed with the surrounding environment. (5) Geometric transformation. The pictures can be translated, rotated and scaled by these operations.Parameterized modeling method of this system has the characteristics of high efficiency, clear categorizing parameters, convenient operating system and prompt analysis.