<html><head></head><body dir="auto" style="word-wrap: break-word; -webkit-nbsp-mode: space; line-break: after-white-space;" class="ApplePlainTextBody"><div class="ApplePlainTextBody"><br><br><blockquote type="cite">On 11 Jan 2019, at 16:48, Terrence Moran <tpm92@cornell.edu> wrote:<br><br>Hello all,<br><br>I am trying to refine a mesh to be very fine around a curve and very coarse away from it. This works very well using one or two curves (photo 1) using Distance and Threshold. When I try and do more curves (completing a circuit) the mesh becomes fine everywhere on the plane (Photo 2) ignoring the mesh size at DistMax. I understand there are other functions such as Box or cylinder but I need this to work for any geometry. My code is below, It is a simple example of a box. The loop is to find the lines that make up the surface on which I am trying to refine the boundary. Any help would be greatly appreciated!<br><br></blockquote><br>Setting Mesh.CharacteristicLengthExtendFromBoundary = 0; should do the trick.<br><br>Christophe<br><br><br><br><br><blockquote type="cite">Thanks,<br>Terrence <br><photo1.PNG><br><photo2.PNG><br>//+<br>SetFactory("OpenCASCADE");<br>ShapeFromFile("box.iges")<br>//+<br>lns[];<br>h = 0;<br>For i In {1:newl-1}<br> pnts[] = Boundary{Line{i};}; <br> Printf("line %g",i);<br> Printf("point one = %g",pnts[0]);<br> Printf("point two = %g",pnts[1]);<br> coords1[] = Point{pnts[0]};<br> coords2[] = Point{pnts[1]};<br> If(coords1[2]==254 && coords2[2]==254)// 254=top surface z coord<br> Printf("line %g is on boundary",i);<br> lns[h] = i;<br> h = h+1; <br> EndIf <br>EndFor<br>Field[1] = Distance;<br>Field[1].EdgesList = {lns[]};<br>Field[1].NNodesByEdge = 100;<br>Field[2] = Threshold;<br>Field[2].IField = 1;<br>Field[2].LcMin = 0.5;<br>Field[2].LcMax = 100;<br>Field[2].DistMin = 1;<br>Field[2].DistMax = 50;<br>Background Field = 2;<br><br><br>_______________________________________________<br>gmsh mailing list<br>gmsh@onelab.info<br>http://onelab.info/mailman/listinfo/gmsh<br></blockquote><br>— <br>Prof. Christophe Geuzaine<br>University of Liege, Electrical Engineering and Computer Science <br>http://www.montefiore.ulg.ac.be/~geuzaine<br><br>Free software: http://gmsh.info | http://getdp.info | http://onelab.info<br><br></div></body></html>