Abstract: The present invention relates to a glossy part of radiation is estimated coming from a surface illuminated by area light source(s) having source surface(s) (A) bounded by edge curves, by determining integrand function(s) representative of that glossy part. The latter corresponding to an integration of the integrand function along the edge curves. In this respect, the integrand function(s) is/are approximated by means of peak-shape function(s) having a known antiderivative over the edge curves, and the glossy part is computed from analytical expressions associated with integrations of the peak-shape function(s) along the edge curves. Such invention can offer efficient and accurate computation for specular part of reflection as well as glossy transmission, and is notably relevant to real-time rendering.

Abstract: A method and device for enriching the content associated with a first element of a depth map, the depth map being associated with a scene according to a point of view. Thereafter, at least a first information representative of a variation of depth in the first element in the space of the depth map is stored into the depth map.

Abstract: Shadow is computed in a lighted 3D scene, based on a depth map. For each depth map element, following geometric information is stored: depth value, coordinates of vertices and local depth variation of a surface element. Also, ray intersection is tested for a pixel with the surface element having depth computed from the depth and local depth variation, taking into account the coordinates of vertices. A minimum depth associated with the surface element is further computed from the geometric information, with which the depth of a pixel is compared. The pixel is classified as lit if the depth is lower than the minimum depth, and as shadowed if the depth is greater and if a ray intersection is found for the pixel with the surface element from the ray intersection testing. The invention can provide a fast solution for high-quality shadow.

Abstract: Shadow is computed in a lighted 3D scene, based on a depth map. For each depth map element, following geometric information is stored: depth value, coordinates of vertices and local depth variation of a surface element. Also, ray intersection is tested for a pixel with the surface element having depth computed from the depth and local depth variation, taking into account the coordinates of vertices. A minimum depth associated with the surface element is further computed from the geometric information, with which the depth of a pixel is compared. The pixel is classified as lit if the depth is lower than the minimum depth, and as shadowed if the depth is greater and if a ray intersection is found for the pixel with the surface element from the ray intersection testing. The invention can provide a fast solution for high-quality shadow.

Abstract: A method and device for establishing a frontier between a first object and at least a second object of a scene in the space of a depth map, at least a part of the first object and at least a part of the at least a second object being visible from the point of view associated with the depth map through a set (3) of elements of the depth map.

Abstract: A glossy part of a radiation coming from a surface illuminated by area light source(s) (21) having source surface(s) (A) bounded by edge curves (210) is estimated, by determining one or more integrand function(s) representative of that glossy part, the latter corresponding to an integration of the integrand function along the edge curves. In this respect, the integrand function(s) is/are approximated by means of at least one ellipsoid-based-peak-shape function(s) having a null first derivative at integration domain bounds, and the glossy part is computed from one or more analytical expression associated with integrations of the ellipsoid-based-peak-shape function(s) along the edge curves.

Abstract: For rendering a specular part of a surface illuminated by an area light source (A), a viewing reflection vector (R) associated with an image to be rendered at a shading point (x) is established. For each spherical edge UiUi+1 of a projected area consisting in a projection of the light source onto a unit sphere centered on the shading point, a local radiance is established by: establishing a normalized projection vector S of the viewing reflection vector onto a plane defined by edge UiUi+1 and the shading point determining if point S associated with vector S lies inside UiUi+1, and if so, performing a halfway transform of Ui; S and Ui+1 and an edge integral on Ui; S and S, Ui+1. An iteration is performed over all edges and the local radiance is summed, the surface being rendered accordingly.

Abstract: A 3D scene illuminated by light sources is rendered on an image grid by path tracing. At least one ray originating from each grid pixel is traced in the 3D scene until it meets an object at a crossing point, that ray is bounced towards one of the light sources, a visibility test is made for that ray between the crossing point and that light source, and a contribution of that light ray is added at the crossing point in carrying out the rendering at the concerned pixel. The visibility tests are carried out over the pixels in a clustered way according to the light sources, the visibility tests being clustered in terms of computations and/or of memory storage in function of the light sources respectively associated with the visibility tests.

Abstract: A method and apparatus for rendering a graphics image having a plurality of pixels is described. The method having and the apparatus being configured to perform the following operations: generating a first sequence of first samples, the first sequence being identical for each pixel of a set of pixels of said graphics image; calculating an interval as a function of a parameter representative of discrepancy of the first sequence; for each pixel, applying a shift to the first samples to obtain a second sequence of second samples, the shift being selected in the interval, the shift being different for at least a part of the pixels of the set; rendering the graphics image by using the second samples.

Abstract: A method and device for estimating the opacity at a point of a scene lit by an area light source and comprising an object defined by a mesh and occluding some of the emitted light. In order to optimize the calculations for live estimation of the opacity, 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, estimating a opacity level depending on coefficients of projection in a function 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 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.

Abstract: The present invention relates to a glossy part of radiation is estimated coming from a surface illuminated by area light source(s) having source surface(s) (A) bounded by edge curves, by determining integrand function(s) representative of that glossy part. The latter corresponding to an integration of the integrand function along the edge curves. In this respect, the integrand function(s) is/are approximated by means of peak-shape function(s) having a known antiderivative over the edge curves, and the glossy part is computed from analytical expressions associated with integrations of the peak-shape function(s) along the edge curves. Such invention can offer efficient and accurate computation for specular part of reflection as well as glossy transmission, and is notably relevant to real-time rendering.

Abstract: A method and device for enriching the content associated with a first element of a depth map, the depth map being associated with a scene according to a point of view. Thereafter, at least a first information representative of a variation of depth in the first element in the space of the depth map is stored into the depth map.

Abstract: A method and device for establishing a frontier between a first object and at least a second object of a scene in the space of a depth map, at least a part of the first object and at least a part of the at least a second object being visible from the point of view associated with the depth map through a set (3) of elements of the depth map.

Abstract: A method and device for estimating the opacity at a point of a scene lit by an area light source and comprising an object defined by a mesh and occluding some of the emitted light. In order to optimize the calculations for live estimation of the opacity, 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, estimating a opacity level depending on coefficients of projection in a function 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 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.