feat: 完善一级关系参数化建模与参数导出

step_editor/step_io.py

@@ -4,6 +4,8 @@ import re
 from pathlib import Path
 
 from OCC.Core.BRepBuilderAPI import BRepBuilderAPI_Transform
+from OCC.Core.BRep import BRep_Builder
+from OCC.Core.BRepTools import breptools
 from OCC.Core.IFSelect import IFSelect_RetDone
 from OCC.Core.Interface import Interface_Static
 from OCC.Core.STEPCAFControl import STEPCAFControl_Reader
@@ -126,6 +128,24 @@ def _write_step(shape: TopoDS_Shape, filename: Path) -> None:
         raise IOError(f"Could not write STEP file: {filename}")
 
 
+def _load_brep_shape(filename: str | Path) -> TopoDS_Shape:
+    path = Path(filename)
+    shape = TopoDS_Shape()
+    builder = BRep_Builder()
+    if not breptools.Read(shape, str(path), builder) or shape.IsNull():
+        raise IOError(f"Could not read BREP file: {path}")
+    return shape
+
+
+def _write_brep(shape: TopoDS_Shape, filename: str | Path) -> None:
+    if shape.IsNull():
+        raise ValueError("Cannot export a null shape.")
+    path = Path(filename)
+    path.parent.mkdir(parents=True, exist_ok=True)
+    if not breptools.Write(shape, str(path)):
+        raise IOError(f"Could not write BREP file: {path}")
+
+
 def _prepare_shape_for_step_export(shape: TopoDS_Shape) -> TopoDS_Shape:
     if shape.IsNull():
         return shape