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</o:shapelayout></xml><![endif]--></head><body lang=EN-US link=blue vlink=purple><div class=WordSection1><p class=MsoNormal>Hello gmsh developers and community<o:p></o:p></p><p class=MsoNormal><o:p> </o:p></p><p class=MsoNormal>First of all “thank you” to the developers and researchers of gmsh for this great project.<o:p></o:p></p><p class=MsoNormal><o:p> </o:p></p><p class=MsoNormal>I have built gmsh 3.0.6 as windows DLL and use it to generate 2d quad meshes from a C++ test application.<o:p></o:p></p><p class=MsoNormal>I create programmatically a .geo file and send it for meshing using the gmsh API.<o:p></o:p></p><p class=MsoNormal>All 2d mesh algorithms are working (BAMG produces bad results but it doesn’t crash) with the exception of DelQuad which crashes in function:<o:p></o:p></p><p class=MsoNormal>backgroundMesh::updateSizes() in these lines:<o:p></o:p></p><p class=MsoNormal> if (s0->second < s1->second)s1->second = std::min(s1->second,_beta*s0->second);<o:p></o:p></p><p class=MsoNormal> else s0->second = std::min(s0->second,_beta*s1->second);<o:p></o:p></p><p class=MsoNormal>Following the debugger I realized that backgroundMesh is called only for DelQuad algorithm.<o:p></o:p></p><p class=MsoNormal>However, the same .geo file, is meshed correctly using the gmsh stand-alone application with DelQuad enabled and produces a very good result.<o:p></o:p></p><p class=MsoNormal>I would appreciate any help on how to achieve the same result using DelQuad from the own test application.<o:p></o:p></p><p class=MsoNormal><o:p> </o:p></p><p class=MsoNormal>The code used to mesh the geo file is:<o:p></o:p></p><p class=MsoNormal><o:p> </o:p></p><p class=MsoNormal>std::string geofile; //..<o:p></o:p></p><p class=MsoNormal>std::string mshfile; //..<o:p></o:p></p><p class=MsoNormal>GmshInitialize();<o:p></o:p></p><p class=MsoNormal>GmshSetOption("General", "Verbosity", 100.);<o:p></o:p></p><p class=MsoNormal>//(1=MeshAdapt, 2=Automatic, 5=Delaunay, 6=Frontal, 7 = BAMG, 8 = DelQuad)<o:p></o:p></p><p class=MsoNormal>GmshSetOption("Mesh", "Algorithm", 8.0);<o:p></o:p></p><p class=MsoNormal>GmshSetOption("Mesh", "RecombineAll", 1.0);<o:p></o:p></p><p class=MsoNormal>GmshSetOption("Mesh", "RecombinationAlgorithm", 1.0);<o:p></o:p></p><p class=MsoNormal>GModel *m = new GModel();<o:p></o:p></p><p class=MsoNormal>if (m->readGEO(geofile.c_str()) == 1) {<o:p></o:p></p><p class=MsoNormal> m->mesh(2);<o:p></o:p></p><p class=MsoNormal> m->indexMeshVertices(true);<o:p></o:p></p><p class=MsoNormal> m->writeMSH(mshfile.c_str());<o:p></o:p></p><p class=MsoNormal>}<o:p></o:p></p><p class=MsoNormal>delete m;<o:p></o:p></p><p class=MsoNormal>GmshFinalize();<o:p></o:p></p><p class=MsoNormal><o:p> </o:p></p><p class=MsoNormal>An example Geo file as produced by my program is:<o:p></o:p></p><p class=MsoNormal><o:p> </o:p></p><p class=MsoNormal>Point(1) = {2.0000000000, 3.0000000000, 0.0000000000} ;<o:p></o:p></p><p class=MsoNormal>Point(2) = {1.0000000000, 3.0000000000, 0.0000000000} ;<o:p></o:p></p><p class=MsoNormal>Point(3) = {0.0000000000, 3.0000000000, 0.0000000000} ;<o:p></o:p></p><p class=MsoNormal>Point(4) = {0.0000000000, 1.5000000000, 0.0000000000} ;<o:p></o:p></p><p class=MsoNormal>Point(5) = {0.0000000000, 0.0000000000, 0.0000000000} ;<o:p></o:p></p><p class=MsoNormal>Point(6) = {1.0000000000, 0.0000000000, 0.0000000000} ;<o:p></o:p></p><p class=MsoNormal>Point(7) = {2.0000000000, 0.0000000000, 0.0000000000} ;<o:p></o:p></p><p class=MsoNormal>Point(8) = {2.0000000000, 1.5000000000, 0.0000000000} ;<o:p></o:p></p><p class=MsoNormal>Line(1) = {1, 2} ;<o:p></o:p></p><p class=MsoNormal>Line(2) = {2, 3} ;<o:p></o:p></p><p class=MsoNormal>Line(3) = {3, 4} ;<o:p></o:p></p><p class=MsoNormal>Line(4) = {4, 5} ;<o:p></o:p></p><p class=MsoNormal>Line(5) = {5, 6} ;<o:p></o:p></p><p class=MsoNormal>Line(6) = {6, 7} ;<o:p></o:p></p><p class=MsoNormal>Line(7) = {7, 8} ;<o:p></o:p></p><p class=MsoNormal>Line(8) = {8, 1} ;<o:p></o:p></p><p class=MsoNormal>Line Loop(1) = { 1,2,3,4,5,6,7,8} ;<o:p></o:p></p><p class=MsoNormal>Plane Surface(1) = {1} ;<o:p></o:p></p><p class=MsoNormal>Transfinite Line {1} = 2 Using Progression 1 ;<o:p></o:p></p><p class=MsoNormal>Transfinite Line {2} = 2 Using Progression 1 ;<o:p></o:p></p><p class=MsoNormal>Transfinite Line {3} = 2 Using Progression 1 ;<o:p></o:p></p><p class=MsoNormal>Transfinite Line {4} = 2 Using Progression 1 ;<o:p></o:p></p><p class=MsoNormal>Transfinite Line {5} = 2 Using Progression 1 ;<o:p></o:p></p><p class=MsoNormal>Transfinite Line {6} = 2 Using Progression 1 ;<o:p></o:p></p><p class=MsoNormal>Transfinite Line {7} = 2 Using Progression 1 ;<o:p></o:p></p><p class=MsoNormal>Transfinite Line {8} = 2 Using Progression 1 ;<o:p></o:p></p><p class=MsoNormal><o:p> </o:p></p><p class=MsoNormal>Thank you in advance<o:p></o:p></p><p class=MsoNormal><o:p> </o:p></p><p class=MsoNormal>Konstantinos Iatridis<o:p></o:p></p><p class=MsoNormal>-itech-<o:p></o:p></p><p class=MsoNormal><o:p> </o:p></p></div></body></html>