ENH: Added flat shading to RenderMaterial

Base/Materials/imstkRenderMaterial.cpp

@@ -175,4 +175,16 @@ RenderMaterial::addTexture(std::shared_ptr<Texture> texture)
     }
     m_textures[texture->getType()] = texture;
 }
+
+void
+RenderMaterial::flatShadingOn()
+{
+    m_flatShading = true;
+}
+
+void
+RenderMaterial::flatShadingOff()
+{
+    m_flatShading = false;
+}
 }

Base/Materials/imstkRenderMaterial.h

@@ -99,6 +99,12 @@ public:
     void addTexture(std::shared_ptr<Texture> texture);
     std::shared_ptr<Texture> getTexture(Texture::Type type);
 
+    ///
+    /// \brief Turn on/off flat shading
+    ///
+    void flatShadingOn();
+    void flatShadingOff();
+
 protected:
     friend class VTKRenderDelegate;
 
@@ -120,6 +126,7 @@ protected:
 
     bool m_stateModified = true; ///< Flag for expensive state changes
     bool m_modified = true; ///< Flag for any material property changes
+    bool m_flatShading = false;
 };
 }
 

Base/Rendering/RenderDelegate/imstkVTKRenderDelegate.cpp

@@ -213,6 +213,14 @@ VTKRenderDelegate::updateActorProperties()
     default:
         actorProperty->SetRepresentationToSurface();
         actorProperty->SetEdgeVisibility(false);
+        if (material->m_flatShading)
+        {
+            actorProperty->SetInterpolationToFlat();
+        }
+        else
+        {
+            actorProperty->SetInterpolationToGouraud();
+        }
         break;
     }