Abstract: Three-dimensional terrain has been used widely in the design and production of virtual outdoor scenes. In order to achieve predictability and controllability of synthesized terrain, a new method for synthesizing realistic terrain was presented based on the controllability of feature sketch and piecing of some hills. Firstly, many hills were generated with different shapes and features by using quadtree structure and improved fractal interpolation method. Then, the required terrain was synthesized by piecing many hills under control of feature sketch. The experimental results show that the method is not only effective and versatile for synthesizing various realistic terrains, but also allow users to control feature and style of synthesized terrain.

Key words: terrain synthesizing, fractal interpolation, feature sketch, quadtree, realistic

摘要： 三维地形在各种虚拟室外场景设计与制作中有着广泛的应用,为实现地形合成结果的可预测性和可控制性,提出一种基于特征草图绘制和独立山体拼合的真实感地形合成算法。首先在四叉树结构细分下借助改进的分形插值方法生成多个不同形状和地表特征的独立山体;然后,在用户绘制的期望地形特征曲线的控制下将一定数量的独立山体自然拼合生成最终的三维地形模型。实验结果表明,算法不仅能有效控制地形合成结果,同时支持多种类型的真实感虚拟地形的合成。

关键词: 地形合成, 分形插值, 特征草图, 四叉树结构, 真实感