Analytic Approximations for Real-Time Area Light Shading Lecocq, Pascal; Dufay, Arthur; Sourimant, Gael ...
IEEE transactions on visualization and computer graphics,
2017-May-1, 2017-05-00, 2017-5-1, 20170501, Letnik:
23, Številka:
5
Journal Article
Recenzirano
We introduce analytic approximations for accurate real-time rendering of surfaces lit by non-occluded area light sources. Our solution leverages the Irradiance Tensors developed by Arvo for the ...shading of Phong surfaces lit by a polygonal light source. Using a reformulation of the 1D boundary edge integral, we develop a general framework for approximating and evaluating the integral in constant time using simple peak shape functions. To overcome the Phong restriction, we propose a low cost edge splitting strategy that accounts for the spherical warp introduced by the half vector parametrization. Thanks to this novel extension, we accurately approximate common microfacet BRDFs, providing a practical method producing specular stretches that closely match the ground truth in real-time. Finally, using the same approximation framework, we introduce support for spherical and disc area light sources, based on an original polygon spinning method supporting non-uniform scaling operations and horizon clipping. Implemented on a GPU, our method achieves real-time performances without any assumption on area light shape nor surface roughness.
We introduce analytic approximations for accurate real-time rendering of surfaces lit by non-occluded area light sources. Our solution leverages the Irradiance Tensors developed by Arvo for the ...shading of Phong surfaces lit by a polygonal light source. Using a reformulation of the 1D boundary edge integral, we develop a general framework for approximating and evaluating the integral in constant time using simple peak shape functions. To overcome the Phong restriction, we propose a low cost edge splitting strategy that accounts for the spherical warp introduced by the half vector parametrization. Thanks to this novel extension, we accurately approximate common microfacet BRDFs, providing a practical method producing specular stretches that closely match the ground truth in real-time. Finally, using the same approximation framework, we introduce support for spherical and disc area light sources, based on an original polygon spinning method supporting non-uniform scaling operations and horizon clipping. Implemented on a GPU, our method achieves real-time performances without any assumption on area light shape nor surface roughness.
We introduce Boundary‐Aware Extinction Maps for interactive rendering of massive heterogeneous volumetric datasets. Our approach is based on the projection of the extinction along light rays into a ...boundary‐aware function space, focusing on the most relevant sections of the light paths. This technique also provides an alternative representation of the set of participating media, allowing scattering simulation methods to be applied on arbitrary volume representations. Combined with a simple out‐of‐core rendering framework, Boundary‐Aware Extinction Maps are valuable tools for interactive applications as well as production previsualization and rendering.
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