Patent ID: 9558586
Date: 2017-01-31
CPC Classifications: G06T

Claim:
1. A method of estimating opacity at a point of a scene, said scene being lit by an area light source, said scene comprising at least one object occluding some of the light emitted by said area light source, said occluding object being defined by a mesh, wherein the method comprises: sampling said area light source in a plurality of samples, for at least one sample of the plurality of samples and for at least one first mesh element of the occluding object visible from the at least one sample, generating one shadow plane per edge of the at least one first mesh element at a rendering pipeline level of graphic processors, computing projection coefficients in a functions base from values representative of the opacity for a set of intersection points between at least one ray having for origin a viewpoint of the scene and crossing the scene and shadow planes crossed by said at least one ray, depending on an angle formed by the normal associated with each shadow plane crossed and by said at least one ray, computing a value representative of a opacity level at a point from said at least one ray from the computed projection coefficients, wherein the opacity level increases along the at least one ray when the angle formed by said at least one ray and the normal associated with a shadow plane crossed by said at least one ray is greater than 90°, and in that the opacity level decreases along the at least one ray when the angle formed by said at least one ray and the normal associated with a shadow plane crossed by said at least one ray is less than 90°, displaying a pixel of an image of said scene, information representative of luminance associated with said pixel being obtained from said value.