Sketcher: Python command to delete all internal geometry and constraints of an sketch

src/Mod/Sketcher/App/SketchObject.cpp

@@ -722,6 +722,23 @@ int SketchObject::delGeometry(int GeoId, bool deleteinternalgeo)
     return 0;
 }
 
+int SketchObject::deleteAllGeometry()
+{
+    std::vector< Part::Geometry * > newVals(0);
+    std::vector< Constraint * > newConstraints(0);
+
+    this->Geometry.setValues(newVals);
+    this->Constraints.setValues(newConstraints);
+
+    this->Constraints.acceptGeometry(getCompleteGeometry());
+    rebuildVertexIndex();
+
+    if(noRecomputes) // if we do not have a recompute, the sketch must be solved to update the DoF of the solver
+        solve();
+
+    return 0;
+}
+
 int SketchObject::toggleConstruction(int GeoId)
 {
     const std::vector< Part::Geometry * > &vals = getInternalGeometry();

src/Mod/Sketcher/App/SketchObject.h

@@ -97,6 +97,8 @@ public:
      \retval int - 0 if successful
      */
     int delGeometry(int GeoId, bool deleteinternalgeo = true);
+    /// deletes all the elements/constraints of the sketch except for external geometry
+    int deleteAllGeometry();
     /// add all constraints in the list
     int addConstraints(const std::vector<Constraint *> &ConstraintList);
     /// add constraint

src/Mod/Sketcher/App/SketchObjectPy.xml

@@ -28,6 +28,11 @@
         <UserDocu>delete a geometric object from the sketch</UserDocu>
       </Documentation>
     </Methode>
+    <Methode Name="deleteAllGeometry">
+        <Documentation>
+            <UserDocu>delete all the geometry objects and constraints from the sketch except external geometry</UserDocu>
+        </Documentation>
+    </Methode>
     <Methode Name="toggleConstruction">
       <Documentation>
         <UserDocu>switch a geometry to a construction line</UserDocu>

src/Mod/Sketcher/App/SketchObjectPyImp.cpp

@@ -213,6 +213,23 @@ PyObject* SketchObjectPy::delGeometry(PyObject *args)
     Py_Return;
 }
 
+PyObject* SketchObjectPy::deleteAllGeometry(PyObject *args)
+{
+    if (!PyArg_ParseTuple(args, ""))
+        return 0;
+    
+    if (this->getSketchObjectPtr()->deleteAllGeometry()) {
+        std::stringstream str;
+        str << "Unable to delete Geometry";
+        PyErr_SetString(PyExc_ValueError, str.str().c_str());
+        return 0;
+    }
+
+    Py_Return;
+}
+
+
+
 PyObject* SketchObjectPy::toggleConstruction(PyObject *args)
 {
     int Index;