EG2016

Permanent URI for this community

https://diglib.eg.org/handle/10.2312/15062

Browse

Browsing EG2016 by Subject "and texture"

Now showing 1 - 6 of 6
  • Thumbnail Image
    Item
    BRDF Representation and Acquisition
    (The Eurographics Association and John Wiley & Sons Ltd., 2016) Guarnera, Dar'ya; Guarnera, Giuseppe Claudio; Ghosh, Abhijeet; Denk, Cornelia; Glencross, Mashhuda; Joaquim Madeira and Gustavo Patow
    Photorealistic rendering of real world environments is important in a range of different areas; including Visual Special effects, Interior/Exterior Modelling, Architectural Modelling, Cultural Heritage, Computer Games and Automotive Design. Currently, rendering systems are able to produce photorealistic simulations of the appearance of many real-world materials. In the real world, viewer perception of objects depends on the lighting and object/material/surface characteristics, the way a surface interacts with the light and on how the light is reflected, scattered, absorbed by the surface and the impact these characteristics have on material appearance. In order to re-produce this, it is necessary to understand how materials interact with light. Thus the representation and acquisition of material models has become such an active research area. This survey of the state-of-the-art of BRDF Representation and Acquisition presents an overview of BRDF (Bidirectional Reflectance Distribution Function) models used to represent surface/material reflection characteristics, and describes current acquisition methods for the capture and rendering of photorealistic materials.
  • Thumbnail Image
    Item
    Compressed Multiresolution Hierarchies for High-Quality Precomputed Shadows
    (The Eurographics Association and John Wiley & Sons Ltd., 2016) Scandolo, Leonardo; Bauszat, Pablo; Eisemann, Elmar; Joaquim Jorge and Ming Lin
    The quality of shadow mapping is traditionally limited by texture resolution. We present a novel lossless compression scheme for high-resolution shadow maps based on precomputed multiresolution hierarchies. Traditional multiresolution trees can compactly represent homogeneous regions of shadow maps at coarser levels, but require many nodes for fine details. By conservatively adapting the depth map, we can significantly reduce the tree complexity. Our proposed method offers high compression rates, avoids quantization errors, exploits coherency along all data dimensions, and is well-suited for GPU architectures. Our approach can be applied for coherent shadow maps as well, enabling several applications, including high-quality soft shadows and dynamic lights moving on fixed-trajectories.
  • Thumbnail Image
    Item
    Near-Instant Capture of High-Resolution Facial Geometry and Reflectance
    (The Eurographics Association and John Wiley & Sons Ltd., 2016) Fyffe, Graham; Graham, Paul; Tunwattanapong, Borom; Ghosh, Abhijeet; Debevec, Paul; Joaquim Jorge and Ming Lin
    We present a near-instant method for acquiring facial geometry and reflectance using a set of commodity DSLR cameras and flashes. Our setup consists of twenty-four cameras and six flashes which are fired in rapid succession with subsets of the cameras. Each camera records only a single photograph and the total capture time is less than the 67ms blink reflex. The cameras and flashes are specially arranged to produce an even distribution of specular highlights on the face. We employ this set of acquired images to estimate diffuse color, specular intensity, specular exponent, and surface orientation at each point on the face. We further refine the facial base geometry obtained from multi-view stereo using estimated diffuse and specular photometric information. This allows final submillimeter surface mesostructure detail to be obtained via shape-from-specularity. The final system uses commodity components and produces models suitable for authoring high-quality digital human characters.
  • Thumbnail Image
    Item
    Real-Time Rendering of Heterogeneous Translucent Materials with Dynamic Programming
    (The Eurographics Association, 2016) Ozawa, Tadahiro; Okamoto, Midori; Kubo, Hiroyuki; Morishima, Shigeo; Luis Gonzaga Magalhaes and Rafal Mantiuk
    Subsurface scattering is important to express translucent materials such as skin, marble and so on realistically. However, rendering translucent materials in real-time is challenging, since calculating subsurface light transport requires large computational cost. In this paper, we present a novel algorithm to render heterogeneous translucent materials using Dijkstra's Algorithm. Our two main ideas are follows: The first is fast construction of the graph by solid voxelization. The second is voxel shading like initialization of the graph. From these ideas, we obtain maximum contribution of emitted light on whole surface in single calculation. We realize real-time rendering of animated heterogeneous translucent objects with simple compute and our approach does not require any precomputation.
  • Thumbnail Image
    Item
    Real-time Rendering of Heterogeneous Translucent Objects using Voxel Number Map
    (The Eurographics Association, 2016) Mochida, Keisuke; Okamoto, Midori; Kubo, Hiroyuki; Morishima, Shigeo; Luis Gonzaga Magalhaes and Rafal Mantiuk
    Rendering of tranlucent objects enhances the reality of computer graphics, however, it is still computationally expensive. In this paper, we introduce a real-time rendering technique for heterogeneous translucent objects that contain complex structure inside. First, for the precomputation, we convert mesh models into voxels and generate Look-Up-Table in which the optical thickness between two surface voxels is stored. Second, we compute radiance in real-time using the precomputed optical thickness. At this time, we generate Voxel-Number-Map to fetch the texel value of the Look-Up-Table in GPU. Using Look-Up-Table and Voxel-Number-Map, our method can render translucent objects with cavities and different media inside in real-time.
  • Thumbnail Image
    Item
    Texel Shading
    (The Eurographics Association, 2016) Hillesland, Karl E.; Yang, J. C.; T. Bashford-Rogers and L. P. Santos
    We have developed a texture space shading system built on modern graphics hardware. It begins with a conventional rasterization stage, but records texel accesses as shading work rather than running a shade per pixel. Shading is performed by a separate compute stage, storing the results in a texture. As a baseline, the texels correspond to those required for mipmapped texturing. A final stage collects data from the texture. Storing results in a texture allows for reuse across frames. We also show how adapting shade rate to less than once per pixel further increases performance. We vary shading load to show when these techniques provide a performance win, with up to 4.1x speedup in our experiments at shading times less than 4 ms.