Mesh Simplification Algorithm Based On TIN Model

The scene simulation has been applied to various fields with the progress made in scene simulation. It has brought great convenience for product design and display. The flight scene simulation is the application of scene simulation in flight simulators. Scene simulation provides a more realistic 3D environment for the whole simulation system and it has been widely used in military training and exercises, especially in the area of aircraft simulation. In the process of building a large-scale 3D scene, because of improving of complexity of virtual scene, it needs more graphics datum to render. Yet some datum sizes are larger than what the computer graphics hardware can display in real-time. The available method to solve above problems is simplifying complicate three-dimension models through replacing complicate original models with simple geometry models to reduce the data quantity of models and improve the application efficiency.This paper discusses the mesh simplification algorithm based on quadric error metric, principle of the quadric error metric, process of the model simplification and the optimal location of the new vertex in detail. Because the quadric error metrics can not keep important geometric features of the model surface well, the paper proposes a mesh simplification algorithm based on quadric error metric. The quadric error metric uses the geometric distance as simplification criteria. The distance metric is very efficient in measuring geometric error, but it is difficult to distinguish important shape features such as a high-curvature region even though it has a small distance metric. The paper considers both the local curvature and the size of the incident edges around the vertex on the basis of the quadric error metrics and this method not only can reflect changes on the model surface but also can maintain many important geometric features after the large scale simplification.Finally, developed a mesh simplification software with VC++6.0 and OpenGL. The experimental results show that this algorithm maintains many important geometric features after large scale simplification and the shape of the whole model is also maintained better.