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We present a new method for real-time render- ing of multiple recursions of reflections and refractions. The method uses the strengths of real-time ray tracing for objects close to the camera, by storing them in a per-frame constructed bounding volume hierarchy (BVH). For objects further from the camera, rasterization is used to create G-buffers which store an image-based representation of the sce

Abstract in UndeterminedThis paper describes a methodology for the optimization of portable parallel signal processing applications specified by dataflow programs. The use of dataflow as a programming model for signal processing applications targeting parallel platforms provides an important advantage versus the traditional sequential programming paradigm: the portability of parallelism. The paper

Computing accurate visibility for thin primitives, such as hair strands, fur, grass, at all scales remains difficult or expensive. To that end, we present an efficient visibility algorithm based on spatial line sampling, and a novel intersection algorithm between line sample planes and Bezier splines with varying thickness. Our algorithm produces accurate visibility both when the projected width o

HLA DR4-DQ8 and DR3-DQ2 haplotypes account for 89% of newly diagnosed cases of type 1 diabetes (T1D) in Sweden. The presence of a single copy of DQ6 confers protection. The aim of the present study is to evaluate whether the risk conferred by high risk HLA DR and DQ to T1D is similar in all regions of Sweden and see whether there are any significant regional differences. The subjects comprised 799

Social differences in the role of habits in health-related behaviour are explored within both sociology and economics, where we define habits as non-reflective, repetitive behaviour. The corresponding theoretical perspectives are the habitus theory, the theory of individualization, and habits as rational decision rules. Sixteen thematically structured interviews are analysed using qualitative meth

Computer generated imagery is used in a wide range of disciplines, each with different requirements. As an example, real-time applications such as computer games have completely different restrictions and demands than offline rendering of feature films. A game has to render quickly using only limited resources, yet present visually adequate images. Film and visual effects rendering may not have st

We present a novel visibility algorithm for rendering motion blur with per-pixel anti-aliasing. Our algorithm uses a number of line samples over a rectangular group of pixels, and together with the time dimension, a two-dimensional spatio-temporal visibility problem needs to be solved per line sample. In a coarse culling step, our algorithm first uses a bounding volume hierarchy to rapidly remove

NURBS (Non-uniform rational B-splines) surfaces are one of the most useful primitives employed for high quality modeling in CAD/CAM tools and graphics software. Since direct evaluation of NURBS surfaces on the GPU is a highly complex task, the usual approach for rendering NURBS is to perform the conversion into Bezier surfaces on the CPU, and then evaluate and tessellate them on the GPU. In this p

We present two novel culling tests for rasterization of simultaneous depth of field and motion blur. These tests efficiently reduce the set of xyuvt samples that need to be coverage tested within a screen space tile. The first test finds linear bounds in ut - and vt -space using a separating line algorithm. We also derive a hyperplane in xyuvt - space for each triangle edge, and all samples outside

In this short note, we argue that performance per watt, which is often cited in the graphics hardware industry, is not a particularly useful unit for power efficiency in scientific and engineering discussions. We argue that joules per task and watts are more reasonable units. We show a concrete example where nanojoules per pixel is much more intuitive, easier to compute aggregate statistics from,

Despite its long history, the Theory of Characteristic Modes has only been utilized in antenna design for perfect electric conductors. This is due to computational problems associated with dielectrics and magnetic materials. In particular, the symmetric form of the PMCHWT surface formulation for the Method of Moments (MoM) solves for both external (real) and internal (non-real) resonances of a str

In this paper, we present a new approach to conservative bounding of displaced Bézier patches. These surfaces are expected to be a common use case for tessellation in interactive and real-time rendering. Our algorithm combines efficient normal bounding techniques, min-max mipmap hierarchies and oriented bounding boxes. This results in substantially faster convergence for the bounding volumes of di

U ranijim istraživanjima ratnog nasilja, tokom rata u Bosni i Hercegovini, naglašavana je važnost priča ŽRTAVA ali fokus analize nije bio usmjeren na priče o ratnom nasilju, niti su analizirani poslijeratni intervjui kao produkt međuljudske interakcije. Ovom studijom pokušava se popuniti ta praznina analiziranjem priča osoba koje su preživjele rat u sjeverozapadnoj Bosni i Hercegovini. Prvi cilj s

Dataflow descriptions are a natural match to application areas such as signal processing, cryptography, networking, image processing, and media coding. This paper addresses the problem of efficiently executing the basic elements of a dataflow program, its actors, written in a language such as MPEG's RVC-CAL. Using actor machines as an execution model for dataflow actors, we devise a metric for mea

This paper presents the development of a non-dimensional model of a continuous cross-flow atomic layer deposition (ALD) reactor with temporally separated precursor pulsing and a structured model-based methodology for scaling up the substrate dimensions. The model incorporates an ALD gas–surface reaction kinetic mechanism for the deposition of thin ZnO films from Zn(C2H5)2 and H2O precursors that w

A fundamental part of many computer algorithms involves traversing a binary tree. One notable example is traversing a space-partitioning acceleration structure when computing ray-traced images. Traditionally, the traversal requires a stack to be temporarily stored for each ray, which results in both additional storage and memory-bandwidth usage. We present a novel algorithm for traversing a binary

In this paper, we present a new color buffer compression algorithm for floating-point buffers. It can operate in either an approximate (lossy) mode or in an exact (lossless) mode. The approximate mode is error-bounded and the amount of introduced accumulated error is controlled via a few parameters. The core of the algorithm lies in an efficient representation and color space transform, followed b