EGGH02: SIGGRAPH/Eurographics Workshop on Graphics Hardware 2002

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https://diglib.eg.org/handle/10.2312/333

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Browsing EGGH02: SIGGRAPH/Eurographics Workshop on Graphics Hardware 2002 by Subject "I.3.1 [Computer Graphics]"

Now showing 1 - 6 of 6
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    Comparing Reyes and OpenGL on a Stream Architecture
    (The Eurographics Association, 2002) Owens, John D.; Khailany, Brucek; Towles, Brian; Dally, William J.; Thomas Ertl and Wolfgang Heidrich and Michael Doggett
    The OpenGL and Reyes rendering pipelines each render complex scenes from similar scene descriptions but differ in their internal pipeline organizations. While the OpenGL organization has dominated hardware architectures over the past twenty years, a Reyes organization differs in several important ways from OpenGL, including a shader coordinate system that supports coherent texture accesses, a single shader in the vertex stage, and tessellation and sampling instead of triangle rasterization. Hardware for the OpenGL pipeline has been well-studied, but the lack of a hardware Reyes implementation has prevented a comparison between the two pipelines. We analyze and compare implementations of an OpenGL and a Reyes pipeline on the Imagine stream processor, a high performance programmable processor for media applications. This comparison both demonstrates the applicability of Reyes for hardware implementation and exposes many issues that architects will face in implementing Reyes in hardware, in particular the need for efficient subdivision algorithms and implementations.
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    Efficient Partitioning of Fragment Shaders for Multipass Rendering on Programmable Graphics Hardware
    (The Eurographics Association, 2002) Chan, Eric; Ng, Ren; Sen, Pradeep; Proudfoot, Kekoa; Hanrahan, Pat; Thomas Ertl and Wolfgang Heidrich and Michael Doggett
    Real-time programmable graphics hardware has resource constraints that prevent complex shaders from rendering in a single pass. One way to virtualize these resources is to partition shading computations into multiple passes, each of which satisfies the given constraints. Many such partitions exist for a shader, but it is important to find one that renders efficiently. We present Recursive Dominator Split (RDS), a polynomial-time algorithm that uses a cost model to find near-optimal partitions of arbitrarily complex shaders. Using a simulator, we analyze partitions for architectures with different resource constraints and show that RDS performs well on different graphics architectures. We also demonstrate that shader partitions computed by RDS can run efficiently on programmable graphics hardware available today.
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    High-Quality Unstructured Volume Rendering on the PC Platform
    (The Eurographics Association, 2002) Guthe, Stefan; Roettger, Stefan; Schieber, Andreas; Strasser, Wolfgang; Ertl, Thomas; Thomas Ertl and Wolfgang Heidrich and Michael Doggett
    For the visualization of volume data the application of transfer functions is used widely. In this area the preintegration technique allows high quality visualizations and the application of arbitrary transfer functions. For regular grids, this approach leads to a two-dimensional pre-integration table which easily fits into texture memory. In contrast to this, unstructured meshes require a three-dimensional pre-integration table. As a consequence, the available texture memory limits the resolution of the pre-integration table and the maximum local derivative of the transfer function. Discontinuity artifacts arise if the resolution of the pre-integration table is too low. This paper presents a novel approach for accurate rendering of unstructured grids using the multi-texturing capabilities of commodity PC graphics hardware. Our approach achieves high quality by reconstructing the colors and opacities of the pre-integration table using the high internal precision of the pixel shader. Since we are using standard 2D multi-texturing we are not limited in the size of the pre-integration table. By combining this approach with a hardware-accelerated calculation of the pre-integration table, we achieve both high quality visualizations and interactive classification updates.
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    Interactive Rendering of Atmospheric Scattering Effects Using Graphics Hardware
    (The Eurographics Association, 2002) Dobashi, Yoshinori; Yamamoto, Tsuyoshi; Nishita, Tomoyuki; Thomas Ertl and Wolfgang Heidrich and Michael Doggett
    To create realistic images using computer graphics, an important element to consider is atmospheric scattering, that is, the phenomenon by which light is scattered by small particles in the air. This effect is the cause of the light beams produced by spotlights, shafts of light, foggy scenes, the bluish appearance of the earth s atmosphere, and so on. This paper proposes a fast method for rendering the atmospheric scattering effects based on actual physical phenomena. In the proposed method, look-up tables are prepared to store the intensities of the scattered light, and these are then used as textures. Realistic images are then created at interactive rates by making use of graphics hardware.
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    SaarCOR - A Hardware Architecture for Ray Tracing
    (The Eurographics Association, 2002) Schmittler, Jörg; Wald, Ingo; Slusallek, Philipp; Thomas Ertl and Wolfgang Heidrich and Michael Doggett
    The ray tracing algorithm is well-known for its ability to generate high-quality images and its flexibility to support advanced rendering and lighting effects. Interactive ray tracing has been shown to work well on clusters of PCs and supercomputers but direct hardware support for ray tracing has been difficult to implement. In this paper, we present a new, scalable, modular, and highly efficient hardware architecture for real-time ray tracing. It achieves high performance with extremely low memory bandwidth requirements by efficiently tracing bundles of rays. The architecture is easily configurable to support a variety of workloads. For OpenGL-like scenes our architecture offers performance comparable to state-of-the-art rasterization chips. In addition, it supports all the usual ray tracing features including exact shadows, reflections, and refraction and is capable of efficiently handling complex scenes with millions of triangles. The architecture and its performance in different configurations is analyzed based on cycle-accurate simulations.
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    VIZARD II: A Reconfigurable Interactive Volume Rendering System
    (The Eurographics Association, 2002) Meißner, M.; Kanus, U.; Wetekam, G.; Hirche, J.; Ehlert, A.; Straßer, W.; Doggett, M.; Forthmann, P.; Proksa, R.; Thomas Ertl and Wolfgang Heidrich and Michael Doggett
    This paper presents a reconfigurable, hardware accelerated, volume rendering system for high quality perspective ray casting. The volume rendering accelerator performs ray casting by calculating the path of the ray through the volume using a programmable Xilinx Virtex FPGA which provides fast design changes and low cost development. Volume datasets are stored on the card in low profile DIMMs with standard connectors allowing both, large datasets up to 1 GByte with 32 bit per voxel, and easy upgrades to larger memory capacities. Per-sample Phong shading and post-classification is performed in hardware, giving immediate feedback to changes in the visualization of a dataset. Adding new features, such as pre-integrated classification, can be accomplished using the existing card without expensive and time consuming redesigns. The card can also be used for medical image reconstruction by reconfiguring the FPGA broadening its usefulness for end users. For the first time, users are able to generate high quality perspective images as required for applications such as virtual endoscopy and colonoscopy, and stereoscopic image generation.