Improved Partition Algorithm between Triangulated Irregular Network
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摘要: 三角网切割是实现三维地质建模和模型分析的关键算法, 它的效率直接决定了建模算法的效率.通过建立三角网的方向包围盒(oriented bounding box, OBB) 树实现曲面间的碰撞检测, 然后对发生相交的三角形对统一计算交点, 通过对顶点坐标归一化完成曲面切割后的快速重构, 并针对不同的曲面类型采用不同的切割分类方法进行2侧切割结果的划分.阐述了算法的实现过程并展示了切割后的图形效果.Abstract: The partition algorithms between triangulated irregular network are key algorithms for building and analyzing 3D geology models. Their efficiency determines the model building efficiency. To improve the algorithm, this paper first realizes collision detection by building OBB (oriented-bounding box) trees, and then calculates the intersection points of cutting triangle pairs. Through normalizing the vertex coordinates, the algorithm provides a method for the rapid reconstruction of the geology model. The algorithm uses different partition methods based on different partition types. This paper gives a detailed description of the algorithm's process and demonstrates a cut effect of triangulated irregular network.
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Key words:
- TIN /
- intesection /
- OBBT /
- normalization /
- partition /
- projection
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