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Chapter 7
Conclusions and future work
At the outset of this thesis, a technique was sought that provided the following three features:
1. Allow large and complex procedural content to be created quickly.
2. Provide an interface that is usable by novice and non-technical users.
3. Maintain the flexibility afforded by parametrised procedural models.
Although it has been explained how an adjectival interface would satisfy these requirements, it is worth revisiting these points again, armed with the full knowledge of the technique.
As Chapter 2 demonstrated, the field of procedural modelling is well-researched and continues to evolve and improve. Progressively more complex content can be generated in decreasing amounts of time, in part due to the acceleration of hardware, but also due to the increased sophistication of the procedural techniques available. As such, the problem of quickly generating large and complex content is already solved, through the harnessing of procedural methods “under the hood” by the adjectival interface.
In Chapter 1, it was noted that a key problem with technology was that humans are unable to keep up with the rate of technological development. This is closely tied to the concept of providing an interface that is usable by novice and non-technical users — if a novice user is able to easily make use of the latest technology through an intermediate interface, then the problem of humans keeping up with technology is no longer an issue. As humans communicate using language, the overhead for a user to adapt to an adjectival interface is arguably much less than for a parametrised interface — which is verified by the results presented in Chapter 6.
Finally, by employing procedural techniques for the actual creation of content, there is no sacrifice in flexibility. One could argue that the adjectival interface on its own is less flexible, but the goal
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was not to replace procedural techniques, and rather to augment them with a more usable interface
— in this, the adjectival interface presented is a success. Chapter 6 showed that users were able to generate content with an adjectival interface that more faithfully fulfilled a specific task, which in itself is fair proof that no flexibility has been sacrificed. Furthermore, since the adjectival interface is implemented as a layer on top of procedural techniques, it does not preclude a user from stripping away the adjectival interface and interacting directly with the procedural parameters. The adjectival interface can thus serve as a form of intrinsic scaffolding, or be used for a rapid approximation that is later refined through adjustments to the underlying procedural parameters.
7.1 Motivational summary
Having re-iterated how the final technique addresses the goals of this thesis, we now summarise the motivations that guided the direction of this research, and which culminated in the final system presented.
Having identified that procedural models are immensely powerful but unwieldy to use, an alternative interface to those models was sought. By modelling the interface as an extra layer of abstraction above the procedural models, the problem of modelling is reduced to finding a suitable mapping from adjectival descriptors to procedural parameters — this was discussed in Chapter 3. By restricting the focus of the thesis to parametrised procedural models, and using scalar values to represent varying degrees of quantification for adjectival descriptors, finding this mapping was shown to be equiv-alent to finding a multi-dimensional function approximation. Various techniques for finding such an approximation are available, and these were discussed in Chapter 4. The specific application of function approximation to an adjectival interface was the focus of Chapter 5, and a suitable func-tion approximafunc-tion scheme was chosen. Domain-specific problems were also noted and appropriate solutions developed; these included:
• Identifying that the approximation of the inverse function, f−1, was more suitable for the mapping between adjective space and parameter space, and determining appropriate methods for dealing with the inverse.
• Developing suitable methods for representing adjectives in a format suitable for numerical function approximation.
• Providing for a dynamic adjective space, by the novel extension of radial basis function net-works to include certainty values, thus allowing for easy inclusion of the semantic network information provided by WordNet.
Finally, in Chapter 6, the overall implementation was tested and evaluated. An experiment was designed to compare and contrast the effectiveness of the adjectival interface, against an interface allowing for direct specification of the procedural parameters. Both qualitative and quantitative