Furniture Design Ideas

Saito and Takahashi [181] recognized the importance of depth-buffer-differen­ces for obtaining important lines. The models they dealt with are, however, smooth surfaces in contrast to the decayed surfaces of foliage. In the same way as discontinuities of the first and second order are appropriate for the pro­duction of important lines on smooth objects, discontinuities of […]

As discussed at the beginning of this chapter, in the past diverse attempts were made in which trees were illustrated as skeletons with a number of different objects representing the leaves or leaf clusters. This idea can be generalized with the introduction of so-called “abstract draw­ing primitives”. These are polygons always facing the viewer, similar […]

There is a large number of different illustration styles for plants. At the begin­ning of Chap. 9 some examples were shown that only let us anticipate in how many different styles a tree can be drawn. A comprehensive demonstration of all the methods is not possible within the context of this book. However, dif­ferent approaches […]

A number of works on nonphotorealistic rendering were introduced by the David Salesin’s group at the University of Washington. Instead of defining lines individually with the path-and-stroke metaphor, so-called “stroke tex­tures” are introduced. Here, a texture consisting of strokes is generated for various gray scales and viewing angles. This texture can be applied for au­tomatic […]

Not only the production of synthetic plant sketches, but also the entire area of nonphotorealistic rendering will be continuously investigated during the years to come. The subject has been in discussion since the 1990s, and today the second phase in investigating the problems has been reached, with some no­table attempts to systemize the area (see […]

In contrast to photorealistic landscape images, the rendering of synthetic plant and landscape sketches has undergone little research so far. However, the al­ready-addressed areas of application in architecture and landscaping require this kind of rendering. Currently, prefabricated images, which are combined via computer, most often must suffice. In addition, there are several collections of images […]

As already discussed, in our system the vegetation is represented by plant mod­els and ecosystem data files. To deal with the extremely large geometric com­plexity of entire landscapes, in two ways hierarchical data structures were im­plemented: firstly for the handling of complex single plants, and secondly for the representation of large amounts of small plants. […]

Each plant is divided into two subgeometries, one is represented by points, the other by lines. The decision on what approximation to use is currently pro­vided by the user. In the future, however, this will be determined automatically through geometric analysis of the model structure. As a further step, the user determines the visual importance […]

All point-based methods have in common the need to change their representa­tion at one point back to a polygonal model, which can result in visual artifacts. Rossignac and Borrel [179] try to solve this problem by merging closely posi­tioned vertices within a set of surfaces without being concerned about whether or not they belong to […]

A method that does not need special knowledge of the model, and which is not only applicable to trees or plants, is presented by Shade et al. [195, 196]. They solve the problem of the earlier-mentioned occluded pixels and resulting holes by storing all occluded pixels during the production of a source image for theimage-based […]