EGGH03: SIGGRAPH/Eurographics Workshop on Graphics Hardware 2003

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https://diglib.eg.org/handle/10.2312/332

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Browsing EGGH03: SIGGRAPH/Eurographics Workshop on Graphics Hardware 2003 by Subject "I.3.3 [Computer Graphics]"

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    Automatic Shader Level of Detail
    (The Eurographics Association, 2003) Olano, Marc; Kuehne, Bob; Simmons, Maryann; M. Doggett and W. Heidrich and W. Mark and A. Schilling
    Current graphics hardware can render procedurally shaded objects in real-time. However, due to resource and performance limitations, interactive shaders can not yet approach the complexity of shaders written for film production and software rendering, which may stretch to thousands of lines. These constraints limit not only the complexity of a single shader, but also the number of shaded objects that can be rendered at interactive rates. This problem has many similarities to the rendering of large models, the source of extensive research in geometric simplification and level of detail. We introduce an analogous process for shading : shader simplification. Starting from an initial detailed shader, shader simplification automatically produces a set of simplified shaders or a single new shader with extra level-of-detail parameters that control the shader execution. The resulting level-of-detail shader can automatically adjust its rendered appearance based on measures of distance, size, or importance, as well as physical limits such as rendering time budget or texture usage. We demonstrate shader simplification with a system that automatically creates shader levels of detail to reduce the number of texture accesses, one common limiting factor for current hardware.
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    The FFT on a GPU
    (The Eurographics Association, 2003) Moreland, Kenneth; Angel, Edward; M. Doggett and W. Heidrich and W. Mark and A. Schilling
    The Fourier transform is a well known and widely used tool in many scientific and engineering fields. The Fourier transform is essential for many image processing techniques, including filtering, manip- ulation, correction, and compression. As such, the computer graphics community could benefit greatly from such a tool if it were part of the graphics pipeline. As of late, computer graphics hardware has become amazingly cheap, powerful, and flexible. This paper describes how to utilize the current gener- ation of cards to perform the fast Fourier transform (FFT) directly on the cards. We demonstrate a system that can synthesize an image by conventional means, perform the FFT, filter the image, and finally apply the inverse FFT in well under 1 second for a 512 by 512 image. This work paves the way for performing complicated, real-time image processing as part of the rendering pipeline.
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    GPU Algorithms for Radiosity and Subsurface Scattering
    (The Eurographics Association, 2003) Carr, Nathan A.; Hall, Jesse D.; Hart, John C.; M. Doggett and W. Heidrich and W. Mark and A. Schilling
    We capitalize on recent advances in modern programmable graphics hardware, originally designed to support advanced local illumination models for shading, to instead perform two different kinds of global illumination models for light transport. We first use the new floating-point texture map formats to find matrix radiosity solutions for light transport in a diffuse environment, and use this example to investigate the differences between GPU and CPU performance on matrix operations. We then examine multiple-scattering subsurface light transport, which can be modeled to resemble a single radiosity gathering step. We use a multiresolution meshed atlas to organize a hierarchy of precomputed subsurface links, and devise a three-pass GPU algorithm to render in real time the subsurface-scattered illumination of an object, with dynamic lighting and viewing.