Add NiFloatInterpController abstraction

components/nif/controller.cpp

@@ -170,25 +170,13 @@ namespace Nif
         data.post(nif);
     }
 
-    void NiAlphaController::read(NIFStream *nif)
+    void NiFloatInterpController::read(NIFStream *nif)
     {
         Controller::read(nif);
         data.read(nif);
     }
 
-    void NiAlphaController::post(NIFFile *nif)
+    void NiFloatInterpController::post(NIFFile *nif)
-    {
-        Controller::post(nif);
-        data.post(nif);
-    }
-
-    void NiRollController::read(NIFStream *nif)
-    {
-        Controller::read(nif);
-        data.read(nif);
-    }
-
-    void NiRollController::post(NIFFile *nif)
     {
         Controller::post(nif);
         data.post(nif);

components/nif/controller.hpp

@@ -143,23 +143,16 @@ public:
     void post(NIFFile *nif);
 };
 
-class NiAlphaController : public Controller
+struct NiFloatInterpController : public Controller
 {
-public:
     NiFloatDataPtr data;
 
     void read(NIFStream *nif);
     void post(NIFFile *nif);
 };
 
-class NiRollController : public Controller
+class NiAlphaController : public NiFloatInterpController { };
-{
+class NiRollController : public NiFloatInterpController { };
-public:
-    NiFloatDataPtr data;
-
-    void read(NIFStream *nif);
-    void post(NIFFile *nif);
-};
 
 class NiGeomMorpherController : public Controller
 {