VMV15

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https://diglib.eg.org/handle/10.2312/13268

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Browsing VMV15 by Subject "Color"

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    The Bounced Z-buffer for Indirect Visibility
    (The Eurographics Association, 2015) Nalbach, Oliver; Ritschel, Tobias; Seidel, Hans-Peter; David Bommes and Tobias Ritschel and Thomas Schultz
    Synthesizing images of animated scenes with indirect illumination and glossy materials at interactive frame rates commonly ignores indirect shadows. In this work we extend a class of indirect lighting algorithms that splat shading to a framebuffer - we demonstrate deep screen space and ambient occlusion volumes - to include indirect visibility. To this end we propose the bounced z-buffer: While a common z-buffered framebuffer, at each pixel, maintains the distance from the closest surface and its radiance along a direction from the camera to that pixel, our new representation contains the distance from the closest surface and its radiance after one indirect bounce into a certain other direction. Consequently, with bounced z-buffering, only the splat from the nearest emitter in one direction contributes to each pixel. Importance-sampling the bounced directions according to the product of cosine term and BRDF allows to approximate full shading by a simple sum of neighboring framebuffer pixels.
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    Extrapolating Large-Scale Material BTFs under Cross-Device Constraints
    (The Eurographics Association, 2015) Steinhausen, Heinz Christian; Brok, Dennis den; Hullin, Matthias B.; Klein, Reinhard; David Bommes and Tobias Ritschel and Thomas Schultz
    In this paper, we address the problem of acquiring bidirectional texture functions (BTFs) of large-scale material samples. Our approach fuses gonioreflectometric measurements of small samples with few constraint images taken on a flatbed scanner under semi-controlled conditions. Underlying our method is a lightweight texture synthesis scheme using a local texture descriptor that combines shading and albedo across devices. Since it operates directly on SVD-compressed BTF data, our method is computationally efficient and can be implemented on a moderate memory footprint.