refactor(meshGeneration): working on gmsh to generate curvilinear isogeomatric spherical mesh

utils/meshGeneration/generateMesh.py

@@ -1,37 +1,39 @@
-import pygmsh
 import meshio
-import numpy as np
-from math import sqrt
-
 import argparse
+import subprocess as sp
+import os
 
-def mesh_size_callback(dim, tag, x, y, z, lc, a, b, k):
-    r = np.sqrt(x**2 + y**2 + z**2)
-    size = a + (b-a) * (1-np.exp(-k*r))
-    return size
+def generateMesh(coreMeshRes, outerMeshRes, k, order):
+    # gmsh sphere.geo -3 -setnumber Parameters/Order 1 -setnumber Parameters/CoreRes 0.2 -setnumber Parameters/OuterRes 0.4 -setnumber Parameters/K 2.0 -o sphere_order2.msh
+    gmsh_cmd = [
+        'gmsh',
+        'sphere.geo',  # Path to your GMSH geometry file
+        '-3',  # Generate 3D mesh
+        '-setnumber', 'Parameters/Order', str(order),
+        '-setnumber', 'Parameters/CoreRes', str(coreMeshRes),
+        '-setnumber', 'Parameters/OuterRes', str(outerMeshRes),
+        '-setnumber', 'Parameters/K', str(k),
+        '-o', 'sphere.vtk',  # Output mesh file
+        '-format', 'vtk'
 
-def generate_spherical_mesh(radius=1.0, coreRes = 0.1, outRes = 0.1, k = 2):
-    with pygmsh.occ.Geometry() as geom:
-        originPoint = geom.add_point([0.0, 0.0, 0.0], mesh_size=coreRes)
-        geom.add_ball([0.0, 0.0, 0.0], 1.0)
-
-        geom.set_mesh_size_callback(lambda dim, tag, x, y, z, lc: mesh_size_callback(dim, tag, x, y, z, lc, coreRes, outRes, k))
-        mesh = geom.generate_mesh(verbose=True)
-
-    return mesh
-
-
-def write_mfem_mesh(meshData, filename):
-    meshio.write(filename, meshData, file_format='gmsh22')
+    ]
+    # Use popen to run
+    process = sp.Popen(gmsh_cmd)
+    stdout, stderr = process.communicate()
+    if process.returncode != 0:
+        print(f"Error generating mesh: {stderr.decode()}")
 
 if __name__ == '__main__':
     parser = argparse.ArgumentParser(description='Generate a spherical mesh')
-    parser.add_argument('--radius', type=float, default=1.0, help='Radius of the sphere')
-    parser.add_argument('--coreMeshRes', type=float, default=0.01, help='Core Mesh Resolution')
-    parser.add_argument('--outerMeshRes', type=float, default=0.1, help='Outer Mesh Resolution')
+    parser.add_argument('--coreMeshRes', type=float, default=0.1, help='Core Mesh Resolution target')
+    parser.add_argument('--outerMeshRes', type=float, default=0.3, help='Outer Mesh Resolution target')
     parser.add_argument('--k', type=float, default=2, help='Mesh size scaling factor')
-    parser.add_argument('--output', type=str, default='sphere.msh', help='Output file name')
+
+    # Add argument for element order
+    parser.add_argument('--order', type=int, default=2, help='Mesh element order (e.g., 1 for linear, 2 for quadratic)')
+    parser.add_argument('--output', type=str, default='sphere.vtk', help='Output file name')
     args = parser.parse_args()
 
-    meshData = generate_spherical_mesh(args.radius, args.coreMeshRes, args.outerMeshRes, args.k)
-    write_mfem_mesh(meshData, args.output)
+    # Generate the mesh
+    generateMesh(args.coreMeshRes, args.outerMeshRes, args.k, args.order)
+