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The construction of parametric curve and surface plays an important role in computer aided geometric design (CAGD), computer aided design (CAD), and geometric modeling. In this paper, we define a new kind of blending functions associated with a real points set, called generalized toric-Bernstein (GT-Bernstein) basis functions. Then, the generalized toric-Bézier (GT-Bézier) curves and surfaces are constructed based on the GT-Bernstein basis functions, which are the projections of the (irrational) toric varieties in fact and the generalizations of the classical rational Bézier curves/surfaces and toric surface patches. Furthermore, we also study the properties of the presented curves and surfaces, including the limiting properties of weights and knots. Some representative examples verify the properties and results.

The spatial expression and ordering of social processes is one of the primary aims of architecture. Such is the view of Zaha Hadid Architects (ZHA), where Shajay Bhooshan heads the computation and design group (CoDe). Here he explains how the practice has followed in the footsteps of the automotive, aircraft and shipbuilding industries in adopting a hybrid approach to design development. As demonstrated by a mathematics-themed gallery conceived by ZHA for London's Science Museum, it assimilates historical knowledge while facilitating fabrication and allowing for future flexibility. [ABSTRACT FROM AUTHOR]

The Bernstein–Fourier algorithm for the evaluation of polynomial curves is extended for the evaluation of polynomial tensor product surfaces. Under a natural hypothesis, accurate evaluation of Bézier curves and surfaces through several algorithms is discussed. Numerical experiments comparing the accuracy of the corresponding Horner, de Casteljau, VS and Bernstein–Fourier algorithms are presented. [ABSTRACT FROM AUTHOR]

Abstract: One hundred years after the introduction of the Bernstein polynomial basis, we survey the historical development and current state of theory, algorithms, and applications associated with this remarkable method of representing polynomials over finite domains. Originally introduced by Sergei Natanovich Bernstein to facilitate a constructive proof of the Weierstrass approximation theorem, the leisurely convergence rate of Bernstein polynomial approximations to continuous functions caused them to languish in obscurity, pending the advent of digital computers. With the desire to exploit the power of computers for geometric design applications, however, the Bernstein form began to enjoy widespread use as a versatile means of intuitively constructing and manipulating geometric shapes, spurring further development of basic theory, simple and efficient recursive algorithms, recognition of its excellent numerical stability properties, and an increasing diversification of its repertoire of applications. This survey provides a brief historical perspective on the evolution of the Bernstein polynomial basis, and a synopsis of the current state of associated algorithms and applications. [Copyright &y& Elsevier]

Abstract: Given four polynomial or rational Bézier curves defining a curvilinear rectangle, we consider the problem of constructing polynomial or rational tensor-product Bézier patches bounded by these curves, such that they are geodesics of the constructed surface. The existence conditions and interpolation scheme, developed in a general context in earlier studies, are adapted herein to ensure that the geodesic-bounded surface patches are compatible with the usual polynomial/rational representation schemes of CAD systems. Precise conditions for four Bézier curves to constitute geodesic boundaries of a polynomial or rational surface patch are identified, and an interpolation scheme for the construction of such surfaces is presented when these conditions are satisfied. The method is illustrated with several computed examples. [Copyright &y& Elsevier]