OwningVector disambiguate const/non-const fcts

Base/Types/OwningVector.h

@@ -56,10 +56,16 @@ public:
 
     size_t size() const { return m_v.size(); }
     bool empty() const { return m_v.empty(); }
-    T* const& operator[](int i) const { return m_v.operator[](i); }
-    T* const& at(int i) const { return m_v.at(i); }
-    T* const& front() const { return m_v.front(); }
-    T* const& back() const { return m_v.back(); }
+
+    const T* operator[](int i) const { return m_v.operator[](i); }
+    T* operator[](int i) { return m_v.operator[](i); }
+    const T* at(int i) const { return m_v.at(i); }
+    T* at(int i) { return m_v.at(i); }
+    const T* front() const { return m_v.front(); }
+    T* front() { return m_v.front(); }
+    const T* back() const { return m_v.back(); }
+    T* back() { return m_v.back(); }
+
     int index_of(const T* t) const { return Vec::indexOfPtr(t, m_v); }
 
     void delete_element(T* e)

Device/Mask/MaskStack.cpp

@@ -83,6 +83,6 @@ size_t MaskStack::numberOfMasks() const
 
 std::pair<IShape2D*, bool> MaskStack::patternAt(size_t iMask) const
 {
-    MaskPattern* pat = m_stack.at(iMask);
+    const MaskPattern* pat = m_stack.at(iMask);
     return {pat->shape, pat->doMask};
 }