基于分形维数的地表模型多分辨率动态绘制

以基于分形维数的树状结构组织三维地表网格模型,实现了与视点相关的连续多分辨率地表模型简化及实时绘制.算法分为预处理和实时绘制两个阶段.在预处理阶段,通过分形维数评价地表的复杂度,建立自适应的树状结构,计算出所有顶点的误差值.在绘制阶段，则根据视距、视角等因素动态地确定需保留的顶点集,并采用受限四叉树方法实时三角化得到所需分辨率下的三角网格近似模型.该算法具有两个优点:一个是地表模型的分层区域划分考虑了地形本身的复杂度;另一个是建立了视点相关各参数与所采用的分辨率表示的直接关系.实验表明，此算法简单、有效,支持对地表模型的交互式实时动态绘制.

Level of Detail Dynamic Rendering of Terrain Model Based on Fractal Dimension

In this paper, the authors use a tree structure based on fractal dimension to organize the 3D-terrain mesh model and realize real time continuous view-dependent level of detail rendering of terrain data. The total algorithm can be divided into two stages: preprocessing and rendering. In preprocessing, it builds an adaptive tree structure by considering the complexity of terrain area which was evaluated by the fractal dimension. Then it generates triangular mesh approximation by dynamically determining reserved data points according to the view related factors and performing a real time restricted quadtree triangulation. Experimental results show that this algorithm is simple and efficient, and supports the interactive real time dynamic rendering of terrain model.