Estimates of the scaled selection coefficient, gamma of Sawyer and Hartl, are shown to be remarkably robust to population subdivision. Estimates of mutation parameters and divergence times, in contrast, are very sensitive to subdivision. These results follow from an analysis of natural selection and genetic drift in the island model of subdivision in the limit of a very large number of subpopul...

The hemisphere subdivision technique is an importancedriven technique using a triangular adaptive subdivision of a hemisphere in order to guide the rays shot from a patch [17]. The purpose of this technique is to take advantage of the knowledge of an environment in order to optimise the space distribution of rays shot in radiosity algorithms. In this paper, we present a new approach of the hemi...

Hierarchical subdivision techniques remove the need for a-priori meshing of surfaces when approximating global illumination. In addition they allow progressive reenement of the solution. However, when subdivision is based upon Monte Carlo methods, due to the stochastic nature of such techniques, subdivision decisions cannot be made unless a suuciently large number of samples have been considere...

This paper presents approaches of incorporating subdivision techniques in the rendering process for computer-generated line drawings. A new method for accelerating silhouette detection is introduced. This “silhouette propagation” method gains its strength from being intertwined with the 3D subdivision process. Another technique reduces the number of 3D subdivision steps necessary for high-quali...

Hierarchical subdivision techniques remove the need for a-priori meshing of surfaces when approximating global illumination. In addition they allow progressive re nement of the solution. However, when subdivision is based upon Monte Carlo methods, due to the stochastic nature of such techniques, subdivision decisions cannot be made unless a su ciently large number of samples have been considere...

Given a non-planar graph G with a subdivision of K5 as a subgraph, we can either transform the K5-subdivision into a K3,3-subdivision if it is possible, or else we obtain a partition of the vertices of G\K5 into equivalence classes. As a result, we can reduce a projective planarity or toroidality algorithm to a small constant number of simple planarity checks [6] or to a K3,3-subdivision in the...

Subdivision surfaces refer to a class of modelling schemes that define an object through recursive subdivision starting from an initial control mesh. Similar to B-splines, the final surface is defined by the vertices of the initial control mesh. These surfaces were initially conceived as an extension of splines in modelling objects with a control mesh of arbitrary topology. They exhibit a numbe...