Remaining Questions
The number and variety of algorithmic methods that can be applied to model plants and in particular trees convincingly faithfully, is indeed surprising. It may be due to the relatively nonspecific structure of the botanical models that several good approximation procedures could be found. At the same time, the factual findings address the question of whether there exists - below the level of the procedures used so far - a parameter or a rule set for botanical objects. This basic set would then have been projected more or less intuitively onto the different parameters of the individual procedures used so far.
Moreover, the possibility exists that in one or more procedures, for instance those of de Reffye and Holton, different aspects are applied with regards to the approximation of natural growth procedures, and that, although each method already yields satisfactory models, a combination could result in an even more complete model. Such a combinatory method could mean a reduction of the multiple parameters, which still have to be edited manually in order to obtain a visually attractive model. Furthermore, the parameter area could be limited to such an extent that, for example, only statistically meaningful trees would be producible or that a realistic overall design would automatically result from the parameters.
None of these possibilities can be clarified here, since botany is also still far away from perfecting such simple descriptions. The rule-based methods of the next chapter work with similarly complex parameter sets, but by their nature they are substantially more general, and, at the same time, they are able to produce very diverse structures.
From a more pragmatic view, still another solution appears promising: If the arrangement of a parameter set and its editing are so efficiently solved by a system that the user can change parameters fast and comfortably, then the user is, despite a perhaps not yet optimal choice of the parameters, able to generate a seemingly correct model efficiently. The methods presented in Chap. 6 suggest this possibility.
