［1］Cosman M A, Mathiesen A E et al. A new visual system to support advanced requirements[A]. In: Proceedings of IMAGE V Conference[C], Arizona, USA, 1990:370～380.
[2]
［2］Falby J S, Zyda M J et al. NPSNET: Hierarchical data structures for real-time three-dimensional visual simulation[J]. Computers & Graphics, 1993,17(1):65～69.
[3]
［3］Peter Lindstrom, David Koller et al. Real-time, continuous level of detail rendering of height fields[A]. In: SIGGRAPH \'96 Conference Proceedings[C], New Orleans, Louisiana. USA 1996:109～118.
[4]
［4］Stefan Rttger, Wolfgang Heidrich, Philipp Slusallek et al. Real-time generation of continuous levels of detail for height fields[R].Technical Report 13/1997, Universita ¨t Erlangen-Nürnberg.
[5]
［5］Mark Duchaineau, Murray Wolinski et al. ROAMing terrain: Real-time, optimally adapting meshes[A]. In:Proceedings of the Conference on Visualization \'97[C], Phoenix, AZ USA. 1997:81～88.
[6]
［6］Douglas D H. Experiments to locate ridges and channels to create a new type of digital elevation model[J]. Cartographica,1986,23(4):29～61.
[7]
［7］Fowler R J, Little J J. Automatic extraction of irregular network digital terrain models[A]. In:Proceedings of SIGGRAPH\'79[C]. Computer Graphics,19,13(2):144～151.
[8]
［8］L De Floriani, E Puppo. Hierarchical triangulation for multiresolution surface description[J]. ACM Transactions on Graphics, 1995,14(4):363～411.
[9]
［9］L De Floriani, P Magillo, E Puppo. Building and traversing a surface at variable resolution[A]. In:Proceedings IEEE Visualization\'97 [C], Phoenix, AZ,USA,1997:81～88.
[10]
［10］Hugues Hoppe. View-dependent refinement of progressive meshes[A]. In:Proceedings SIGGRAPH\'97[C], Los Angeles, USA,1997:189～198.
[11]
［11］Hugues Hoppe. Smooth view-dependent level-of-detail control and its application to terrain rendering[A]. In:Proceedings IEEE Visualization \'98[C]. North California USA, 1998:35～42.
