LayerInterface always has non-nullptr roughness

Sample/Interface/LayerInterface.cpp

@@ -16,10 +16,15 @@
 #include "Base/Util/Assert.h"
 #include "Sample/Interface/LayerRoughness.h"
 
-LayerInterface::LayerInterface()
-    : m_top_layer(nullptr)
-    , m_bottom_layer(nullptr)
+LayerInterface::LayerInterface(const Layer* top_layer, const Layer* bottom_layer,
+                               const LayerRoughness* layerRoughness)
+    : m_top_layer(top_layer)
+    , m_bottom_layer(bottom_layer)
+    , m_roughness(layerRoughness)
 {
+    ASSERT(top_layer);
+    ASSERT(bottom_layer);
+    ASSERT(layerRoughness);
 }
 
 LayerInterface::~LayerInterface() = default;
@@ -29,35 +34,11 @@ LayerInterface* LayerInterface::clone() const
     throw std::runtime_error("LayerInterface::clone -> Not allowed to clone.");
 }
 
-LayerInterface* LayerInterface::createInterface(const Layer* top_layer, const Layer* bottom_layer,
-                                                const LayerRoughness* roughness)
-{
-    auto* result = new LayerInterface();
-    result->setLayersTopBottom(top_layer, bottom_layer);
-    if (roughness)
-        result->setRoughness(roughness);
-    return result;
-}
-
-void LayerInterface::setRoughness(const LayerRoughness* roughness)
-{
-    m_roughness.reset(roughness);
-}
-
 std::vector<const INode*> LayerInterface::nodeChildren() const
 {
     return std::vector<const INode*>() << m_roughness;
 }
 
-//! Sets links to the layers above and below the interface.
-
-void LayerInterface::setLayersTopBottom(const Layer* top_layer, const Layer* bottom_layer)
-{
-    ASSERT(top_layer && bottom_layer);
-    m_top_layer = top_layer;
-    m_bottom_layer = bottom_layer;
-}
-
 std::string LayerInterface::validate() const
 {
     return "";

Sample/Interface/LayerInterface.h

@@ -24,22 +24,17 @@
 class Layer;
 class LayerRoughness;
 
-//! Interface between two layers, possibly with roughness.
+//! Interface between two layers, always with roughness.
 
 class LayerInterface : public ISampleNode {
 public:
+    LayerInterface(const Layer* top_layer, const Layer* bottom_layer,
+                   const LayerRoughness* layerRoughness);
     ~LayerInterface() override;
 
     LayerInterface* clone() const override;
     std::string className() const final { return "LayerInterface"; }
 
-    //! Creates rough interface between two layers
-    static LayerInterface* createInterface(const Layer* top_layer, const Layer* bottom_layer,
-                                           const LayerRoughness* roughness);
-
-    //! Sets roughness of the interface.
-    void setRoughness(const LayerRoughness* roughness);
-
     //! Returns roughness of the interface.
     const LayerRoughness* roughness() const;
 
@@ -52,9 +47,6 @@ public:
     std::string validate() const override;
 
 private:
-    void setLayersTopBottom(const Layer* top_layer, const Layer* bottom_layer);
-    LayerInterface();
-
     const Layer* m_top_layer;                          //!< pointer to the layer above interface
     const Layer* m_bottom_layer;                       //!< pointer to the layer below interface
     std::unique_ptr<const LayerRoughness> m_roughness; //!< roughness of the interface

Sample/Multilayer/MultiLayer.cpp

@@ -70,10 +70,8 @@ void MultiLayer::addLayerExec(const Layer& layer, const LayerRoughness* roughnes
 
     if (numberOfLayers()) { // not the top layer
         const Layer* last_layer = m_layers.back();
-        const LayerRoughness* new_roughness =
-            roughness && roughness->sigma() != 0.0 ? roughness->clone() : nullptr;
-        m_interfaces.push_back(
-            LayerInterface::createInterface(last_layer, new_layer, new_roughness));
+        const LayerRoughness* new_roughness = roughness ? roughness->clone() : new LayerRoughness;
+        m_interfaces.push_back(new LayerInterface(last_layer, new_layer, new_roughness));
 
     } else { // the top layer
         if (new_layer->thickness() != 0.0)