“…Pioneered by Requicha and Voelcker in the 70 's [1977] and defined by regularized Boolean set operations on halfspaces, CSG has become one of the most popular approaches for solid modeling, due to its guarantee of solidity and the ease of control. The most commonly used halfspaces are parameterized primitives, such as boxes, spheres, cones, cylinders, and tori, but other forms of halfspaces have been extensively studied in the research community, such as implicit functions [Nielson 2004;Pasko et al 1995], parametric surfaces [Casale and Bobrow 1989;Keyser et al 2004], and meshes [Bernstein and Fussell 2009;Douze et al 2017;Feito et al 2013;Pavić et al 2010;Smith and Dodgson 2007;Wang 2010;Xu and Keyser 2013]. CSG has been extended to support other types of constructive modeling operations such as blending [Rossignac and Requicha 1984], offseting [Rossignac and Requicha 1986], and warping [Wyvill et al 1999].…”