Structured mesh with quads for triangles

meshes/triangle.geo

@@ -0,0 +1,30 @@
+// Gmsh project created on Thu Feb 25 18:26:02 2016
+Point(1) = {-1, 0, 0, 1.0};
+Point(2) = {1, 0, 0, 1.0};
+Point(3) = {0, 1.4142135623731, 0, 1.0};
+Point(4) = {0, 0, 0, 1.0};
+Point(5) = {0.5, 0.70710678118655, 0, 1.0};
+Point(6) = {-0.5, 0.70710678118655, 0, 1.0};
+Point(7) = {0, 0.471404520791033, 0, 1.0};
+Line(1) = {1, 4};
+Line(2) = {4, 7};
+Line(3) = {7, 6};
+Line(4) = {6, 1};
+Line(5) = {4, 2};
+Line(6) = {2, 5};
+Line(7) = {5, 7};
+Line(8) = {5, 3};
+Line(9) = {3, 6};
+Line Loop(10) = {4, 1, 2, 3};
+Plane Surface(11) = {10};
+Line Loop(12) = {2, -7, -6, -5};
+Plane Surface(13) = {12};
+Line Loop(14) = {3, -9, -8, 7};
+Plane Surface(15) = {14};
+Transfinite Line {4, 2, 6} = 10 Using Progression 1;
+Transfinite Line {1, 3, 8} = 10 Using Progression 1;
+Transfinite Line {5, 7, 9} = 10 Using Progression 1;
+Transfinite Surface {11};
+Transfinite Surface {13};
+Transfinite Surface {15};
+Recombine Surface {15, 11, 13};

meshes/triangle_hole.geo

@@ -0,0 +1,61 @@
+
+Point(1) = {-1, 0, 0, 1.0};
+Point(2) = {1, 0, 0, 1.0};
+Point(3) = {0, 1.4142135623731, 0, 1.0};
+Point(4) = {0, 0, 0, 1.0};
+Point(5) = {0.5, 0.70710678118655, 0, 1.0};
+Point(6) = {-0.5, 0.70710678118655, 0, 1.0};
+Point(7) = {0, 0.471404520791033, 0, 1.0};
+Point(8) = {0, 0.171404520791033, 0, 1.0};
+Point(9) = {0.25980762,  0.62140452, 0, 1.0};
+Point(10) = {-0.25980762,  0.62140452, 0, 1.0};
+Point(11) = {0.25980762,  0.32140452, 0, 1.0};
+Point(12) = {-0.25980762,  0.32140452, 0, 1.0};
+Point(13) = {0, 0.771404520791033, 0, 1.0};
+
+Line(1) = {1, 4};
+Line(2) = {4, 2};
+Line(3) = {2, 5};
+Line(4) = {5, 3};
+Line(5) = {3, 6};
+Line(6) = {6, 1};
+Line(7) = {4, 8};
+Line(8) = {5, 9};
+Line(9) = {6, 10};
+Line(10) = {12, 1};
+Line(11) = {11, 2};
+Line(12) = {13, 3};
+Circle(13) = {8, 7, 11};
+Circle(14) = {11, 7, 9};
+Circle(15) = {9, 7, 13};
+Circle(16) = {13, 7, 10};
+Circle(17) = {10, 7, 12};
+Circle(18) = {12, 7, 8};
+
+Line Loop(19) = {10, 1, 7, -18};
+Plane Surface(20) = {19};
+Line Loop(21) = {13, 11, -2, 7};
+Plane Surface(22) = {21};
+Line Loop(23) = {11, 3, 8, -14};
+Plane Surface(24) = {23};
+Line Loop(25) = {8, 15, 12, -4};
+Plane Surface(26) = {25};
+Line Loop(27) = {5, 9, -16, 12};
+Plane Surface(28) = {27};
+Line Loop(29) = {9, 17, 10, -6};
+Plane Surface(30) = {29};
+Transfinite Line {10, 7, 11, 8, 12, 9} = 5 Using Progression 1;
+Transfinite Line {6, 17} = 10 Using Progression 1;
+Transfinite Line {5, 16} = 10 Using Progression 1;
+Transfinite Line {4, 15} = 10 Using Progression 1;
+Transfinite Line {3, 14} = 10 Using Progression 1;
+Transfinite Line {13, 2} = 10 Using Progression 1;
+Transfinite Line {18, 1} = 10 Using Progression 1;
+
+Transfinite Surface {30};
+Transfinite Surface {20};
+Transfinite Surface {22};
+Transfinite Surface {24};
+Transfinite Surface {26};
+Transfinite Surface {28};
+Recombine Surface {30, 28, 26, 24, 22, 20};