13294915
Voxelisation: Modelling for Volume Graphics
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 new practical approach to the voxelisation of data which fills the entire volume. Its use is demonstrated on various datasets such as triangular mesh objects, CT data, and objects defined by trivariate functions.
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.
6680702
Melting Objects
This paper describes a technique for producing realistic animations of melting objects. The work presented here introduces a method that accurately models both thermal flow and the latent heat during the phase change. The mechanism for energy transfer to the model is via both boundary conditions and radiation. Emphasis is made on accurately modelling the solid object and the method is particularly suited to rigid solids with complex surface geometry. The underlying objects are constructed using Volume Graphics modelling techniques (specifically voxelization), and a numerical simulation computes the time-dependent heat flow throughout the object. A technique for computing the phase transition is given, and details for rendering the melting objects are provided. The melting is controlled by material parameters, such as specific heat capacity, thermal conductivity, latent heat and temperature. Examples are given of melting ice and a plastic man.
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.
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.
41482626
A New Approach to the Construction of Surfaces from Contour Data
This paper presents a new approach to the construction of a surface from a stack of contour slices. Unlike most existing methods, this new approach handles ambiguous conditions consistently without employing an algorithm to establish a correspondence between vertices on one contour and those on the next. It is easy to implement and fast to compute, requiring only basic geometric properties, namely closedness and simplicity, to be available with contour data. The advantages of this new approach have also been demonstrated with solutions to a few classical problems from the literature and some practical problems in medical imaging. It can also be applied to geographical surveying and keyframe animations.
15051631
Type Classes with Functional Dependencies
Type classes in Haskell allow programmers to define functions that can be used on a set of different types, with a potentially different implementation in each case. For example, type classes are used to support equality and numeric types, and for monadic programming. A commonly requested extension to support 'multiple parameters' allows a more general interpretation of classes as relations on types, and has many potentially useful applications. Unfortunately, many of these examples do not work well in practice, leading to ambiguities and inaccuracies in inferred types and delaying the detection of type errors. 
 
This paper illustrates the kind of problems that can occur with multiple parameter type classes, and explains how they can be resolved by allowing programmers to specify explicit dependencies between the parameters. A particular novelty of this paper is the application of ideas from the theory of relational databases to the design of type systems.
2346657
ML Typing, Explicit Polymorphism and Qualified Types
The ML type system was originally introduced as a means of identifying a class of terms in a simple untyped language, often referred to as core-ML, whose evaluation could be guaranteed not to “go wrong”. In subsequent work, the terms of core-ML have also been viewed as a ‘convenient shorthand’ for programs in typed languages. Notable examples include studies of ML polymorphism and investigations of overloading, motivated by the use of type classes in Haskell.
43107545
A Theory of Qualified Types
Abstract This paper describes a general theory of overloading based on a system of qualified types. The central idea is the use of predicates in the type of a term, restricting the scope of universal quantification. A corresponding semantic notion of evidence is introduced and provides a uniform framework for implementing applications of this system, including Haskell style type classes, extensible records and subtyping. Working with qualified types in a simple, implicitly typed, functional language, we extend the Damas-Milner approach to type inference. As a result, we show that the set of all possible typings for a given term can be characterized by a principal type scheme, calculated by a type inference algorithm.
6816342
SkipNet: A Scalable Overlay Network with Practical Locality Properties
Scalable overlay networks such as Chord, CAN, Pastry, and Tapestry have recently emerged as flexible infrastructure for building large peer-to-peer systems. In practice, such systems have two disadvantages: They provide no control over where data is stored and no guarantee that routing paths remain within an administrative domain whenever possible. SkipNet is a scalable overlay network that provides controlled data placement and guaranteed routing locality by organizing data primarily by string names. SkipNet allows for both fine-grained and coarse-grained control over data placement: Content can be placed either on a pre-determined node or distributed uniformly across the nodes of a hierarchical naming sub-tree. An additional useful consequence of SkipNet's locality properties is that partition failures, in which an entire organization disconnects from the rest of the system, can result in two disjoint, but well-connected overlay networks.
39305576
Adaptive real-time resource management supporting composition of independently authored time-critical services
This paper describes ongoing investigations at Microsoft Research into algorithms for adaptive real-time scheduling and resource management. We are implementing a system which will allow sets of independently authored real-time applications to be scheduled, providing both initial resource negotiation and dynamic feedback to applications about their resource consumption. Instead of relying on human beings to pre-compute scheduling and resource requirements, applications will be able to dynamically adapt their run-time behavior to the resources available. Under overload conditions, user preferences and policies will be applied in order to bring the total resource requirements within available resources. This will permit chosen applications to continue executing perfectly even while others execute with dynamically renegotiated resource grants or are gracefully shut down, as per user preferences. We believe that this approach will lead to real-time scheduling and resource management algorithms which are appropriate for workstation and home multi-media environments.<<ETX>>