[Gmsh] transfinite BSpine Using Progression

Seiji Adachi seiji.adachi at ibp.fraunhofer.de
Fri Sep 24 11:47:46 CEST 2010


Hello there,

I try to make a 1D mesh on a B-spline curve using progression. 
It seems, however, that the created nodes are not distributed as 
Progression intends. Why? 

In the following example, the mid node on line 1 (lower one 
defined by Line) divides it into 1:2 as "Progression 2.0" is set, 
whereas on line 2 (upper one defined by BSpline), the mid node 
is not distributed at the "right" place but closer to the center. 

I am using gmsh version 2.4.2 on a linux x86_64 machine. 

Regards,

Seiji

///// line.geo
Point(1) = {0.0, 0.0, 0,0};
Point(2) = {10.0, 0.0, 0,0};
Point(3) = {0.0, 1.0, 0,0};
Point(4) = {10.0, 1.0, 0,0};
Point(5) = {5.0, 1.0, 0,0};

Line(1) = {1,2};
BSpline(2) = {3,5,4};

Transfinite Line{1} = 3 Using Progression 2.0;
Transfinite Line{2} = 3 Using Progression 2.0;

/////  line.msh
1 0 0 0
2 10 0 0
3 0 1 0
4 10 1 0
5 5 1 0
6 3.333333345743983 0 0
7 4.043208571157269 0.9999999999999999 0
$EndNodes
$Elements
9
1 15 3 0 1 0 1
2 15 3 0 2 0 2
3 15 3 0 3 0 3
4 15 3 0 4 0 4
5 15 3 0 5 0 5
6 1 3 0 1 0 1 6
7 1 3 0 1 0 6 2
8 1 3 0 2 0 3 7
9 1 3 0 2 0 7 4
$EndElements

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