Abstract: A method and apparatus for detecting a main lighting direction from the input image, which corresponds to a key light. The system is operative to nm on data-parallel architectures allows for incoming light direction estimation in real-time. More particularly, the method and apparatus detect a key, or principal light direction relative to the position/orientation of an acquisition device. It method involves image analysis to find a maximum intensity value, maximal values filtering, and conversion of the input image position to a direction in space.

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 apparatus for detecting a main lighting direction from the input image, which corresponds to a key light. The system is operative to nm on data-parallel architectures allows for incoming light direction estimation in real-time. More particularly, the method and apparatus detect a key, or principal light direction relative to the position/orientation of an acquisition device. It method involves image analysis to find a maximum intensity value, maximal values filtering, and conversion of the input image position to a direction in space.

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 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: A method for visualizing contact between a first object and at least a second object of a virtual scene commences by first associating a first identifier with first pixels associated with the first object and at least a second identifier with second pixels associated with the at least a second object. Thereafter, for at least one first pixel, at least a distance in world space between the at least one first pixel and at least one second pixel located in the neighbourhood of the at least one first pixel, is computed. Then at least a contact between the first object and the at least a second object is visualized if the at least a computed distance remains less than a first threshold distance.

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 estimation of the occlusion at a point P of a virtual environment, the point P belonging to a surface (S) grouping at least some of the points of the virtual environment visible from a viewpoint. In order to improve the display while minimising the required calculation time, the method comprises steps for: estimating intersections between said surface (S) and a plurality of half-lines having as origin said point P, said intersections being estimated by discretization of each half-line of said plurality of half-lines, associating of occlusion factors with the half-lines of said plurality of half-lines having an intersection with said surface (S), said occlusion factors being a function of occlusion distances ?0 separating said point P from said intersections, and estimation of the occlusion in said point P from said estimated intersections.