例子 7

/********************************************************************* 
 *
 *  Gmsh tutorial 7
 * 
 *  各向异性网格、吸引子
 *
 *********************************************************************/

// 我们可以选择新的二维的各向异性网格生成器：

Mesh.Algorithm = 2 ;

// 我们强行使用 4 步 Laplacian 迭代将网格磨光：

Mesh.Smoothing = 4 ;

lc = .1;

Point(1) = {0.0,0.0,0,lc};
Point(2) = {1.2,-0.2,0,lc};
Point(3) = {1,1,0,lc};
Point(4) = {0,1,0,lc};

Line(1) = {3,2};
Line(2) = {2,1};
Line(3) = {1,4};
Line(4) = {4,3};

Line Loop(5) = {1,2,3,4};
Plane Surface(6) = {5};

Point(5) = {0.1,0.2,0,lc};
Point(11) = {0.5,0.5,-1,lc};
Point(12) = {0.5,0.5,0,lc};
Point(22) = {0.6,0.6,1,lc};

Line(5) = {11,22};

Spline(7) = {4,5,12,2};

// 各向异性的吸引子能够定义在点和线上：

Attractor Line{5} = {.1, 0.01, 17};

Attractor Line{1,2} = {0.1, 0.005, 3};
Attractor Line{7} = {0.1, 0.05, 3};