stl_from_vtk

Author: aroccon

post/.DS_Store

@@ -0,0 +1,68 @@
+import vtk
+import os
+
+# PARAMETERS
+data_dir = "/leonardo_scratch/large/userexternal/aroccon0/VANDYKE/post/paraview_hit/output"
+file_pattern = "OUTPAR_*.vtk"
+iso_value = 0.5
+output_dir = "stl"
+array_name = "phi"
+
+os.makedirs(output_dir, exist_ok=True)
+files = sorted(f for f in os.listdir(data_dir) if f.endswith(".vtk"))
+
+for fname in files:
+    step = fname.split("_")[-1].replace(".vtk", "")
+    filepath = os.path.join(data_dir, fname)
+
+    print(f"Processing step {step}")
+
+    # -----------------------------
+    # READ VTK FILE
+    # -----------------------------
+    reader = vtk.vtkGenericDataObjectReader()
+    reader.SetFileName(filepath)
+    reader.Update()
+
+    data = reader.GetOutput()
+
+    # -----------------------------
+    # SELECT SCALAR ARRAY
+    # -----------------------------
+    if data.GetPointData().HasArray(array_name):
+        data.GetPointData().SetActiveScalars(array_name)
+        print("  phi on POINTS")
+    elif data.GetCellData().HasArray(array_name):
+        data.GetCellData().SetActiveScalars(array_name)
+        print("  phi on CELLS")
+    else:
+        raise RuntimeError(f"{array_name} not found in {fname}")
+
+    # -----------------------------
+    # ISO-SURFACE (ParaView Contour)
+    # -----------------------------
+    contour = vtk.vtkContourFilter()
+    contour.SetInputData(data)
+    contour.SetValue(0, iso_value)
+    contour.Update()
+
+    poly = contour.GetOutput()
+    n_cells = poly.GetNumberOfCells()
+    print(f"  contour cells: {n_cells}")
+
+    if n_cells == 0:
+        print("  ⚠️ empty iso-surface, skipping")
+        continue
+
+    # -----------------------------
+    # WRITE STL
+    # -----------------------------
+    outname = os.path.join(output_dir, f"phi_iso_{step}.stl")
+
+    writer = vtk.vtkSTLWriter()
+    writer.SetFileName(outname)
+    writer.SetInputData(poly)
+    writer.SetFileTypeToBinary()
+    writer.Write()
+
+print("✅ All STL files written.")