秋季植物叶子表观的模拟

Simulation of Autumn Leaves

提供了一种采样并生成植物叶子表观的方法,可以非常真实地展现叶子秋季在干枯、老化过程中多种纹理、表观属性的变化.在生成叶子纹理的过程中,有别于以往基于单一材质样本的表观合成技术,采集了大量不同叶子样本表面的双向反射分布函数BRDF和双向透射分布函数BTDF,最终从这些数据中得到叶子衰老过程在老化空间中的表达式和完全分布图.结合植物学知识和所得到的老化空间中的表达式和分布图,可以很好地指导合成秋季不同衰老程度叶子的表观纹理,并能够外插合成采样范围之外的叶子纹理样式.在生成多种不同种类和衰老程度的植物叶子的过程中验证了这种方法的有效性,得到了大量非常接近真实树叶的各种叶子形态和纹理.

This paper presents a method for capturing and efficiently simulating of a large number of plant leaves, realistically showing their weathering process in autumn time with various texture patterns and appearances. In generating the texture patterns of leaves, different from the existing technique that models the appearance manifolds from a single input material sample, this paper captures the BRDF and BTDF properties of leaf surface from multiple various samples, which contribute to a final complete aging manifold representing the appearance change through the aging process of the leaves. Combining this aging manifold representing with botanical knowledge, it can synthesize many different leaves＇ appearance and textures and extrapolate texture patterns out of input samples. The effectiveness of this method is proved in several applications, including subjects with different ages and types. In most eases, it is able to re-produce texture patterns consistent with those observed in nature.