LOD Algorithm of Terrain Based on Conservative Screen Error and Isolated Division of Quad-tree

In order to deal with the problems of enormous data redundancy, single evaluation standard of precision and strong scene of jumping at level switch in static and dynamic level of detail models, an algorithm for regular square grid was proposed. This algorithm reduces the complex computation in real-time expression through terrain tile partition and data pre-progressing, and eliminates dependencies between nodes using isolated division of quad-tree. By building up an evaluation standard based on conservative screen error, jumping feeling is weakened greatly. Finally, cracks between adjacent tiles and nodes are eliminated easily by adding split points and averaging elevation value. Experiment results show that this algorithm has abilities to overcome the shortcoming of the conventional methods and meets the requirements of 3D real-time expression of large-scale terrain. Furthermore, amount of calculation for real-time display is small and frame speed is within 0.03 s.