Abstract: As to generate shadows in an image, the method comprises the steps of: Computing a depth-map that comprises an array of pixels, wherein pixels in the depth-map are associated to a single value corresponding to depth value that indicates a depth from a light source to a portion of nearest occluding object visible through the pixel, projecting a point visible through a pixel of said image into a light space, the result of said projection being a pixel of said depth-map, calculating a distance between the said visible point and the light source, fetching the depth value associated to said pixel of depth-map, computing, for said pixel of said image, an adaptive bias as a function of a predetermined base bias and a relationship between the normal of a surface on which the said visible point is located and incident light direction at said visible point, comparing for said pixel in the image, the distance between said visible point and the light source with the sum of the corresponding depth map value and said ad

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: An environment map representative of lighting information of a real environment. As to enhance the impression of immersion into a virtual environment, the method comprises the steps of acquisition at real time of an image representative of a partial lighting information of said real environment from a digital optical acquisition device, said image comprising a plurality of pixels; and estimation of said environment map by extrapolation of at least a part of said pixels of said image, the extrapolation comprising the application of a first value corresponding to the mean value of the pixels of said image to at least a first part of the environment map.

Abstract: A method for estimating occlusion in a virtual environment comprising at least two objects and observed from a viewpoint. Thereafter, a second item of information representative of the distance separating a second fragment of a second object from the viewpoint according to an observation direction is computed; the second item of information is compared with a first item of information representative of the distance separating a first fragment of a first object from the viewpoint according to the observation direction and is stored in a first buffer memory. If the second item of information is less than the first item of information, then a third item of information representative of attributes associated with the second fragment is estimated, the second item of information is stored in a second buffer memory and the third item of information is stored in a third buffer memory.

Abstract: The invention relates to a method for estimating information representative of a pixel of a virtual object. In order to improve the rendering while minimizing the required calculation time, the method comprises defining a first surface element associated with the pixel according to a direction of observation of the virtual object, the first surface element belonging to a representation of the virtual object according to a first level of detail; associating a second surface element with the first surface element, the second surface element being determined by intersection between the direction of observation and a first parametric surface representing the virtual object according to a second level of detail; estimating the information representative of the pixel according to the second surface element and information associated with the second surface element enabling the virtual object to be represented according to a third level of detail.

Abstract: A method for estimating the quantity of light received by a point M of a heterogeneous participating media, the light being emitted by a light environment. Thereafter, the method comprises estimating, for each point of a first set of points, first values representative of the light attenuation between the considered point and a first surface bounding the media along a plurality of particular directions of light emission, estimating first coefficients of projection by projection of the first values of reduction of light intensity in an orthonormal basis of spherical functions, estimating second values representative of the light attenuation between the point and a second surface along directions, the second surface comprising some of the points of the neighborhood of the point, and estimating the quantity of light received by the point using first coefficients of projection and second values of reduction of light intensity.

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 for estimation of the quantity of light received at a point P of a virtual environment that comprises several first points lit by a light source, these first points forming a plurality of groups each comprising at least one first point is disclosed. In order to improve the display while minimizing the required calculation time, the method estimates the quantity of incident light received at point P by estimating a surface including point P grouping at least some of the points of the virtual environment, estimating a first group of points contributing to the lighting of point P by reflection of the incident light received from the light source based on occlusion information associated with the surface including point P and estimating the quantity of incident light received by the first group of point based on reflectance information associated with such group.

Abstract: A method and device for rendering a synthesis image comprising generating a plurality of elementary geometries (201 . . . 2i2) from an input geometry, a plurality of vertices being associated with each elementary geometry, each vertex being defined with coordinates; assigning an index value (0, 1 . . . 6, 7) to each elementary geometry of at least a part of the elementary geometries (201 . . . 2i2), the index value being estimated from the coordinates associated with at least one vertex of the elementary geometry, and rendering the synthesis image by using the indexed elementary geometries.

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: A method and device for rendering a participating media delimited by a bounding box and rendered from a viewpoint, the media being at a determined distance from the viewpoint according to a viewing direction.

Abstract: A method and device for estimating the quantity of light received by an element of at least a participating medium belonging to a light ray crossing the at least a participating medium and having as origin a light source. As to optimize the estimation and the rendering of the at least a medium, the method comprises determining a pseudo-metric function according to intersection points between the participating medium and the light ray, the pseudo-metric function representing the distance only along the part(s) of the light ray crossing the participating medium; estimating first projection coefficients in a functions basis, the first coefficients being representative of an extinction function along the light ray according to the pseudo-metric function; and estimating the quantity of light received by the element according to the first projection coefficients.

Abstract: To compile a source program comprising first rule(s) not supported by a target environment and to enable the first rule(s) to be executed on the target environment, the method comprises generating a directed graph representative of the source program, generating a first data structure corresponding to a flat representation of the directed graph, first data structure comprising at least a first identifier associated with the at least a first rule, and generating a second data structure comprising first instructions adapted for interpreting the first data structure by using the at least a first identifier, the instructions being coded into a code supported by the target environment.

Abstract: The invention relates to a method for estimation of information representative of a height. In order to minimize the required calculation time, the method comprises steps for: selection of a first point from among a plurality of points of a normal map, a normal being associated with each of the points of said plurality, a reference height being associated with said first point, estimation of a height difference between the first point and a second point of the normal map different from the first point according to the normal associated with the second point and the distance separating the first point from the second point in the normal map.

Abstract: The invention relates to a method for estimating the quantity of light scattered by a heterogeneous participating media, the light being transmitted by a light environment comprising a plurality of light sources. In order to improve the display while minimising the required calculation time, the method comprises steps for: estimation of first projection coefficients in an orthonormal basis of spherical functions, said first projection coefficients being representative of the reduction of light intensity in a point of said media, said estimation of first projection coefficients being carried out for each point of a first set of points of said media, and estimation of the quantity of light scattered by said media, according to at least one scattering direction of the light, using said first estimated projection coefficients.

Abstract: A method for estimating the quantity of light received by a point M of a heterogeneous participating media, the light being emitted by a light environment. Thereafter, the method comprises estimating, for each point of a first set of points, first values representative of the light attenuation between the considered point and a first surface bounding the media along a plurality of particular directions of light emission, estimating first coefficients of projection by projection of the first values of reduction of light intensity in an orthonormal basis of spherical functions, estimating second values representative of the light attenuation between the point and a second surface along directions, the second surface comprising some of the points of the neighbourhood of the point, and estimating the quantity of light received by the point using first coefficients of projection and second values of reduction of light intensity.

Abstract: A method for estimating occlusion in a virtual environment comprising at least two objects and observed from a viewpoint. Thereafter, a second item of information representative of the distance separating a second fragment of a second object from the viewpoint according to an observation direction is computed:, the second item of information is compared with a first item of information representative of the distance separating a first fragment of a first object from the viewpoint according to the observation direction and is stored in a first buffer memory. If the second item of information is less than the first item of information, then a third item of information representative of attributes associated with the second fragment is estimated, the second item of information is stored in a second buffer memory and the third item of information is stored in a third buffer memory.

Abstract: The invention relates to a method for estimating the quantity of light scattered by a heterogeneous participating media. In order to optimise the display while minimising the required calculation time, the method comprises steps for selecting at least one level of spatial subdivision of said media from among a plurality of hierarchic levels of spatial subdivision according to at least one item of error information representative of an attenuation difference in said media according to at least one direction between two consecutive hierarchic levels, and estimating the quantity of light scattered by sampling of said media along at least one scattering direction, the sampling being a function of at least one selected spatial subdivision level.

Abstract: A method for estimation of the quantity of light received at a point P of a virtual environment that comprises several first points lit by a light source, these first points forming a plurality of groups each comprising at least one first point is disclosed. In order to improve the display while minimizing the required calculation time, the method estimates the quantity of incident light received at point P by estimating a surface including point P grouping at least some of the points of the virtual environment, estimating a first group of points contributing to the lighting of point P by reflection of the incident light received from the light source based on occlusion information associated with the surface including point P and estimating the quantity of incident light received by the first group of point based on reflectance information associated with such group.