关键词: 双有理映射, 动直线, 权值

Abstract:  As a special kind of rational mapping, birational mapping can be applied to image warping and domain parametrization of Isogeometric Analysis. By geometric methods, reference [1] constructed a birational mapping on a quadrilateral, but this method needs to compute the weights first and then construct a birational mapping. By the technique of moving lines, a method for the construction of birational map on quadrilateral is proposed. Hence, the computation of weights is not needed here, our method can generate birational map directly. In addition, by choosing different parameter, different birational mappings are calculated. It is easy to verify that the weights of the mapping generated by our method satisfy the weight proportional relation proposed by reference [1]. An example is also provided to illustrate our method.

Key words: birational mapping, moving straight, weight