2872475
Texturing and hypertexturing of volumetric objects
Texture mapping is an extremely powerful and flexible tool for adding complex surface detail to an object. This paper introduces a method of surface texturing and hypertexturing complex volumetric objects in real-time. We employ distance field volume representations, texture based volume rendering and procedural texturing techniques with Shader Model 2.0 flexible programmable graphics hardware. We aim to provide a flexible cross-platform, non vendor specific implementation.
1777796
A System for the Non-Linear Modelling of Deformable Procedural Shapes
This paper describes a fully interactive modelling system, which we have called ClayWorks, for defining the implicit geometry of 3D objects using parametric base primitives and deformations. The goal of this system is to provide a means for describing object data and its creation history by using a series of parametric steps that can be modified post-creation in a non-linearmanner. The advantages of this approach are that unlike other modelling approaches, it enables compact object descriptions, an intuitive modelling process, a simple approach to multiresolution objects, real-time feedback during the modelling process and a render independent object representation.
6934253
Shape representation using space filled sub-voxel distance fields
Voxelisation is the process of converting a source object of any data type into a three-dimensional grid of voxel values. This voxel grid should represent the original object as closely as possible, although some inaccuracies will occur due to the discrete nature of the voxel grid representation. In this paper we report our ongoing research into methods for representing objects as voxelised distance fields, in particular we report fast methods for accurate distance field production. A review of current alternative voxelisation methods is also given.
18480565
Volumes of expression: artistic modelling and rendering of volume datasets
This paper presents the design and implementation of artistic effects in modelling and rendering of volume datasets. Following different stages of a volume-based graphics pipeline, we examine various properties of volume data, and illustrate how expressive and non-photorealistic effects can be implemented. We demonstrate that the true 3D nature of volume data makes it particularly applicable for this use, allowing the addition of complex effects at the modelling stage as well as during rendering.
10888216
Hypertexturing complex volume objects
This paper will examine hypertexture rendering techniques and will demonstrate how volume data sets may be adapted in order for hypertexture to be applied. Details are given of a process for the conversion of complex objects, such as CT scans, into accurate distance fields. Hypertexture is applied to these objects and example renderings include the UNC CThead, a chess piece, a dodecahedron and a tank. Additional information is given about soft objects, density modulation functions, ray marching and controlling hypertexture application.
18996618
The Production of Volume Data from Triangular Meshes Using Voxelisation
Voxelisation is the term given to the process of converting data from one source type into a three dimensional volume of data values. The techniques known collectively as volume visualisation can then be applied to the data in order to produce a graphical representation of the object. This paper gives a practical approach to the voxelisation of data in the form of triangular meshes, and demonstrates the use of the method on various datasets. Visualisation is achieved by a method also described in the paper.
12155836
Using parameterized signatures to express modular structure
Module systems are a powerful, practical tool for managing the complexity of large software systems. Previous attempts to formulate a type-theoretic foundation for modular programming have been based on existential, dependent, or manifest types. These approaches can be distinguished by their use of different quantifiers to package the operations that a module exports together with appropriate implementation types. In each case, the underlying type theory is simple and elegant, but significant and sometimes complex extensions are needed to account for features that are important in practical systems, such as separate compilation and propagation of type information between modules.This paper presents a simple type-theoretic framework for modular programming using parameterized signatures. The use of quantifiers is treated as a necessary, but independent concern. Using familiar concepts of polymorphism, the resulting module system is easy to understand and admits true separate compilation. It is also very powerful, supporting high-order, polymorphic, and first-class modules without further extension.
14189118
A Theory of Qualified Types
• The ability to include local constraints as part of the type of an object. This enables the definition and use of polymorphic overloaded values within a program. ∗An earlier version of this paper was presented at the European Symposium on Programming, Rennes, France, February 1992 and appears in the conference proceedings published in Springer Verlag LNCS Volume 582. †Address from September 1992: Yale University, Department of Computer Science, P.O. Box 2158 Yale Station, New Haven, Connecticut 06520-2158, USA.
14632058
First-class polymorphism with type inference
Languages like ML and Haskell encourage the view of values as first-class entities that can be passed as arguments or results of functions, or stored as components of data structures. The same languages offer parametric polymorphism, which allows the use of values that behave uniformly over a range of different types. But the combination of these features is not supported-- polymorphic values are not first-class. This restriction is sometimes attributed to the dependence of such languages on type inference, in contrast to more expressive, explicitly typed languages, like System F, that do support first-class polymorphism.This paper uses relationships between types and logic to develop a type system, FCP, that supports first-class polymorphism, type inference, and also first-class abstract datatypes. The immediate result is a more expressive language, but there are also long term implications for language design.
23406227
Toward an understanding of similarity judgments for music digital library evaluation
This paper presents an analysis of 7,602 similarity judgments collected for the Symbolic Melodic Similarity (SMS) and Audio Music Similarity and Retrieval (AMS) evaluation tasks in the 2006 Music Information Retrieval Evaluation eXchange (MIREX). We discuss the influence of task definitions, as well as evaluation metrics on user perceptions of music similarity, and provide recommendations for future Music Digital Library/Music Information Retrieval research pertaining to music similarity.
17471768
Navigation via continuously adapted music
Listening to music on personal, digital devices while mobile is an enjoyable, everyday activity. We explore a scheme for exploiting this practice to immerse listeners in navigation cues. Our prototype, Ontrack, continuously adapts audio, modifying the spatial balance and volume to lead listeners to their target destination. An initial lab-based evaluation has demonstrated the approach's efficacy: users were able to complete tasks within a reasonable time and their subjective feedback was positive. Encouraged by these findings, we are building a pocket-sized prototype for further testing.