make const

GUI/Model/Material/MaterialModel.cpp

@@ -80,7 +80,7 @@ MaterialItem* MaterialModel::addSLDMaterial(const QString& name, double sld, dou
     return materialItem;
 }
 
-MaterialItem* MaterialModel::materialFromName(const QString& name)
+MaterialItem* MaterialModel::materialFromName(const QString& name) const
 {
     for (auto* materialItem : topItems<MaterialItem>())
         if (materialItem->materialName() == name)
@@ -89,7 +89,7 @@ MaterialItem* MaterialModel::materialFromName(const QString& name)
     return nullptr;
 }
 
-MaterialItem* MaterialModel::materialFromIdentifier(const QString& identifier)
+MaterialItem* MaterialModel::materialFromIdentifier(const QString& identifier) const
 {
     for (auto* materialItem : topItems<MaterialItem>())
         if (materialItem->identifier() == identifier)

GUI/Model/Material/MaterialModel.h

@@ -33,8 +33,8 @@ public:
     MaterialItem* addRefractiveMaterial(const QString& name, double delta, double beta);
     MaterialItem* addSLDMaterial(const QString& name, double sld, double abs_term);
 
-    MaterialItem* materialFromName(const QString& name);
-    MaterialItem* materialFromIdentifier(const QString& identifier);
+    MaterialItem* materialFromName(const QString& name) const;
+    MaterialItem* materialFromIdentifier(const QString& identifier) const;
 
     //! Returns clone of given material. Clone will get the same material identifier!
     MaterialItem* cloneMaterial(MaterialItem* material);