3Speed Tree CAD v 4.2 User Reference[ Z]. Digimation Inc,2008.
4DEUSSEN O. A framework for geometry generation and rendering of plants with applications in landscape architecture [ J ]. Landscape and Urban Planning,2003,64:105 - 113.
5JESCHKE S, WIMMER M, PURGATHOFER W. Image-based representations for accelerated rendering of complex scenes[ J ]. Proceedings of EUROGRAPHICS ,2005 :1 -20.
