add missing code and readme

crates/opencascade/src/primitives/shape.rs

@@ -495,7 +495,7 @@ impl Shape {
 
         reader.pin_mut().TransferRoots(&ffi::Message_ProgressRange_ctor());
 
-        let inner = ffi::one_shape(&reader);
+        let inner = ffi::one_shape_step(&reader);
 
         Ok(Self { inner })
     }
@@ -518,6 +518,42 @@ impl Shape {
         Ok(())
     }
 
+    pub fn read_iges(path: impl AsRef<Path>) -> Result<Self, Error> {
+        let mut reader = ffi::IGESControl_Reader_ctor();
+
+        let status = ffi::read_iges(reader.pin_mut(), path.as_ref().to_string_lossy().to_string());
+
+        reader.pin_mut().TransferRoots(&ffi::Message_ProgressRange_ctor());
+
+        if status != ffi::IFSelect_ReturnStatus::IFSelect_RetDone {
+            return Err(Error::IgesReadFailed);
+        }
+
+        let inner = ffi::one_shape_iges(&reader);
+
+        Ok(Self { inner })
+    }
+
+    pub fn write_iges(&self, path: impl AsRef<Path>) -> Result<(), Error> {
+        let mut writer = ffi::IGESControl_Writer_ctor();
+
+        let success = ffi::add_shape(writer.pin_mut(), &self.inner);
+
+        if !success {
+            return Err(Error::IgesWriteFailed);
+        }
+
+        ffi::compute_model(writer.pin_mut());
+        let success =
+            ffi::write_iges(writer.pin_mut(), path.as_ref().to_string_lossy().to_string());
+
+        if success {
+            Ok(())
+        } else {
+            Err(Error::IgesWriteFailed)
+        }
+    }
+
     #[must_use]
     pub fn union(&self, other: &Shape) -> BooleanShape {
         let mut fuse_operation = ffi::BRepAlgoAPI_Fuse_ctor(&self.inner, &other.inner);

docs/writing_bindings.md

@@ -191,13 +191,13 @@ Standard_EXPORT TopoDS_Shape OneShape() const;
 Unfortunately, this returns a bare `TopoDS_Shape` so we can't directly bind to it, we'll have to create a wrapper C++ function.
 
 ```rust
-pub fn one_shape(reader: &STEPControl_Reader) -> UniquePtr<TopoDS_Shape>;
+pub fn one_shape_step(reader: &STEPControl_Reader) -> UniquePtr<TopoDS_Shape>;
 ```
 
 and
 
 ```c++
-inline std::unique_ptr<TopoDS_Shape> one_shape(const STEPControl_Reader &reader) {
+inline std::unique_ptr<TopoDS_Shape> one_shape_step(const STEPControl_Reader &reader) {
   return std::unique_ptr<TopoDS_Shape>(new TopoDS_Shape(reader.OneShape()));
 }
 ```
@@ -233,7 +233,7 @@ pub fn from_step_file<P: AsRef<Path>>(path: P) -> Shape {
         read_step(reader.pin_mut(), path.as_ref().to_string_lossy().to_string());
     reader.pin_mut().TransferRoots(&Message_ProgressRange_ctor());
 
-    let inner = one_shape(&reader);
+    let inner = one_shape_step(&reader);
 
     // Assuming a Shape struct has a UniquePtr<TopoDS_Shape> field called `inner`
     Shape { inner }