期刊文献+
共找到8篇文章
< 1 >
每页显示 20 50 100
细分曲面拟合的局部渐进插值方法 被引量:8
1
作者 赵宇 蔺宏伟 鲍虎军 《计算机研究与发展》 EI CSCD 北大核心 2012年第8期1699-1707,共9页
逼近型细分方法生成的细分曲面其品质要优于插值型细分方法生成的细分曲面.然而,逼近型细分方法生成的细分曲面不能插值于初始控制网格顶点.为使逼近型细分曲面具有插值能力,一般通过求解全局线性方程组,使其插值于网格顶点.当网格顶点... 逼近型细分方法生成的细分曲面其品质要优于插值型细分方法生成的细分曲面.然而,逼近型细分方法生成的细分曲面不能插值于初始控制网格顶点.为使逼近型细分曲面具有插值能力,一般通过求解全局线性方程组,使其插值于网格顶点.当网格顶点较多时,求解线性方程组的计算量很大,因此,难以处理稠密网格.与此不同,在不直接求解线性方程组的情况下,渐进插值方法通过迭代调整控制网格顶点,最终达到插值的效果.渐进插值方法可以处理稠密的任意拓扑网格,生成插值于初始网格顶点的光滑细分曲面.并且经证明,逼近型细分曲面渐进插值具有局部性质,也就是迭代调整初始网格的若干控制顶点,且保持剩余顶点不变,最终生成的极限细分曲面仍插值于初始网格中被调整的那些顶点.这种局部渐进插值性质给形状控制带来了更多的灵活性,并且使得自适应拟合成为可能.实验结果验证了局部渐进插值的形状控制以及自适应拟合能力. 展开更多
关键词 渐进插值 逼近型细分格式 局部性质 形状控制 自适应拟合 几何设计
下载PDF
The Odd-Point Ternary Approximating Schemes 被引量:3
2
作者 Ghulam Mustafa Abdul Ghaffar Faheem Khan 《American Journal of Computational Mathematics》 2011年第2期111-118,共8页
We present a general formula to generate the family of odd-point ternary approximating subdivision schemes with a shape parameter for describing curves. The influence of parameter to the limit curves and the sufficien... We present a general formula to generate the family of odd-point ternary approximating subdivision schemes with a shape parameter for describing curves. The influence of parameter to the limit curves and the sufficient conditions of the continuities from C0 to C5 of 3- and 5-point schemes are discussed. Our family of 3-point and 5-point ternary schemes has higher order of derivative continuity than the family of 3-point and 5-point schemes presented by [Jian-ao Lian, On a-ary subdivision for curve design: II. 3-point and 5-point interpolatory schemes, Applications and Applied Mathematics: An International Journal, 3(2), 2008, 176-187]. Moreover, a 3-point ternary cubic B-spline is special case of our family of 3-point ternary scheme. The visual quality of schemes with examples is also demonstrated. 展开更多
关键词 approximating subdivision scheme Derivative CONTINUITY SMOOTHNESS Convergence Shape Parameters and Laurent POLYNOMIAL
下载PDF
Unification and Application of 3-point Approximating Subdivision Schemes of Varying Arity 被引量:1
3
作者 Abdul Ghaffar Ghulam Mustafa Kaihuai Qin 《Open Journal of Applied Sciences》 2012年第4期48-52,共5页
In this paper, we propose and analyze a subdivision scheme which unifies 3-point approximating subdivision schemes of any arity in its compact form and has less support, computational cost and error bounds.? The usefu... In this paper, we propose and analyze a subdivision scheme which unifies 3-point approximating subdivision schemes of any arity in its compact form and has less support, computational cost and error bounds.? The usefulness of the scheme is illustrated by considering different examples along with its comparison with the established subdivision schemes. Moreover, B-splines of degree 4and well known 3-point schemes [1, 2, 3, 4, 6, 11, 12, 14, 15] are special cases of our proposed scheme. 展开更多
关键词 component approximating subdivision scheme BINARY TERNARY a-ary CONTINUITY and Laurent POLYNOMIAL
下载PDF
A UNIFIED THREE POINT APPROXIMATING SUBDIVISION SCHEME
4
作者 Ghulam Mustafa Faheem Khan +1 位作者 Muhammad Sadia Hashmi Muhammad Zeshan Afzal 《Analysis in Theory and Applications》 2011年第1期10-20,共11页
In this paper, we propose a three point approximating subdivision scheme, with three shape parameters, that unifies three different existing three point approximating schemes. Some sufficient conditions for subdivisio... In this paper, we propose a three point approximating subdivision scheme, with three shape parameters, that unifies three different existing three point approximating schemes. Some sufficient conditions for subdivision curve C0 to C3 continuity and convergence of the scheme for generating tensor product surfaces for certain ranges of parameters by using Laurent polynomial method are discussed. The systems of curve and surface design based on our scheme have been developed successfully in garment CAD especially for clothes modelling. 展开更多
关键词 approximating subdivision scheme shape parameters Laurent polynomial
下载PDF
Construction and Application of 3-Point Tensor Product Scheme
5
作者 Abdul Ghaffar Ghulam Mustafa Kaihuai Qin 《Applied Mathematics》 2013年第3期477-485,共9页
In this paper, we propose and analyze a tensor product subdivision scheme which is the extension of three point scheme for curve modeling. The usefulness of the scheme is illustrated by considering different examples ... In this paper, we propose and analyze a tensor product subdivision scheme which is the extension of three point scheme for curve modeling. The usefulness of the scheme is illustrated by considering different examples along with its application in surface modeling. 展开更多
关键词 approximating TENSOR Product subdivision scheme BINARY CONTINUITY Laurent POLYNOMIAL
下载PDF
The 4-Point α-Ary Approximating Subdivision Scheme
6
作者 Abdul Ghaffar Ghulam Mustafa Kaihuai Qin 《Open Journal of Applied Sciences》 2013年第1期106-111,共6页
A general formula for 4-point α-Ary approximating subdivision scheme for curve designing is introduced for any arity α≥2. The new scheme is extension of B-spline of degree 6. Laurent polynomial method is used to in... A general formula for 4-point α-Ary approximating subdivision scheme for curve designing is introduced for any arity α≥2. The new scheme is extension of B-spline of degree 6. Laurent polynomial method is used to investigate the continuity of the scheme. The variety of effects can be achieved in correspondence for different values of parameter. The applications of the proposed scheme are illustrated in comparison with the established subdivision schemes. 展开更多
关键词 approximating subdivision scheme BINARY TERNARY α-Ary CONTINUITY CONVERGENCE and Shape Parameters
下载PDF
用逼近型3^(1/2)细分方法构造闭三角网格的插值曲面 被引量:4
7
作者 邓重阳 《计算机辅助设计与图形学学报》 EI CSCD 北大核心 2010年第2期312-317,326,共7页
为了避免用逼近型3^(1/2)细分方法构造插值曲面过程中出现的烦琐运算,利用3细分方法极限点计算公式,提出一种用逼近型3^(1/2)细分方法构造闭三角网格插值曲面的方法.给定待插值的闭三角网格,先用一个新的几何规则与原3^(1/2)细分方法的... 为了避免用逼近型3^(1/2)细分方法构造插值曲面过程中出现的烦琐运算,利用3细分方法极限点计算公式,提出一种用逼近型3^(1/2)细分方法构造闭三角网格插值曲面的方法.给定待插值的闭三角网格,先用一个新的几何规则与原3^(1/2)细分方法的拓扑规则细分一次得到一个初始网格,用3^(1/2)细分方法细分该初始网格得到插值曲面;新几何规则根据极限点公式确定,保证了初始网格的极限曲面插值待插值的三角网格.由于初始网格的顶点仅与待插值顶点2邻域内的点相关,所以插值曲面具有良好的局部性,即改变一个待插值点的位置时,只影响插值曲面在其附近的形状.该方法中只有确定初始网格顶点的几何规则与原3细分方法不同,故易于整合到原有的细分系统中.实验结果表明,该方法具有计算简单、有充分的自由度调整插值曲面的形状等特点,使得利用3^(1/2)细分方法构造三角网格的插值曲面变得极其简单. 展开更多
关键词 细分曲面 逼近型细分方法 √3细分方法 曲面插值
下载PDF
平面闭合图形的光滑雕刻型面建模 被引量:5
8
作者 陈宇拓 张潇云 +1 位作者 韩旭里 苏畅 《计算机辅助设计与图形学学报》 EI CSCD 北大核心 2009年第4期511-517,共7页
雕刻型面建模是数字化艺术雕刻工艺中重要且复杂的环节.为快速、高质量地建立适应于数字化雕刻的光滑曲面模型,提出一种基于平面闭合图形,采用二次Bzier曲线与细分网格的建模方法.首先分5种情况对约束Delaunay三角化后的闭合图形进行... 雕刻型面建模是数字化艺术雕刻工艺中重要且复杂的环节.为快速、高质量地建立适应于数字化雕刻的光滑曲面模型,提出一种基于平面闭合图形,采用二次Bzier曲线与细分网格的建模方法.首先分5种情况对约束Delaunay三角化后的闭合图形进行处理,然后在相应的区域上建立二次Bzier曲线族,用直线在另一方向连接所有Bzier曲线上的细分点,以形成覆盖相应区域的细分网格曲面.实验结果表明,该方法能够快速地建立光滑的雕刻型面,满足数字化雕刻的实际需求. 展开更多
关键词 雕刻型面建模 逼近多边形 约束DELAUNAY三角化 四点插值细分法 二次Bzier曲线
下载PDF
上一页 1 下一页 到第
使用帮助 返回顶部