Performance Optimizations (#450)

* Make derived transform classes less involved in simulation state
* Add performance measurements in openspaceengine
* Avoid redundant transformation lookups
* Fix bug causing redundant calls to GPULayerManager::bind
* Move water reflectance to alpha component of normal buffer. Remove otherData buffer.

include/openspace/scene/rotation.h

@@ -35,7 +35,7 @@ namespace ghoul { class Dictionary; }
 
 namespace openspace {
 
-struct UpdateData;
+class Time;
 
 namespace documentation { struct Documentation; }
 
@@ -48,14 +48,19 @@ public:
     virtual ~Rotation() = default;
     virtual bool initialize();
     const glm::dmat3& matrix() const;
-    virtual void update(const UpdateData& data);
+    virtual glm::dmat3 matrix(const Time& time) const = 0;
+    void update(const Time& time);
 
     static documentation::Documentation Documentation();
 
 protected:
     Rotation();
+    void requireUpdate();
 
-    glm::dmat3 _matrix;
+private:
+    bool _needsUpdate;
+    double _cachedTime;
+    glm::dmat3 _cachedMatrix;
 };
 
 }  // namespace openspace

include/openspace/scene/scale.h

@@ -35,7 +35,7 @@ namespace ghoul { class Dictionary; }
 
 namespace openspace {
 
-struct UpdateData;
+class Time;
 
 namespace documentation { struct Documentation; }
 
@@ -48,13 +48,18 @@ public:
     virtual ~Scale() = default;
 
     virtual bool initialize();
-    virtual double scaleValue() const;
-    virtual void update(const UpdateData& data);
+    double scaleValue() const;
+    virtual double scaleValue(const Time& time) const = 0;
+    virtual void update(const Time& data);
 
     static documentation::Documentation Documentation();
-
 protected:
-    double _scale;
+    void requireUpdate();
+
+private:
+    bool _needsUpdate;
+    double _cachedTime;
+    double _cachedScale;
 };
 
 }  // namespace openspace

include/openspace/scene/translation.h

@@ -36,7 +36,7 @@ namespace ghoul { class Dictionary; }
 
 namespace openspace {
 
-struct UpdateData;
+class Time;
 
 namespace documentation {  struct Documentation; }
 
@@ -49,10 +49,10 @@ public:
     virtual ~Translation() = default;
     virtual bool initialize();
 
-    virtual glm::dvec3 position() const;
-    virtual void update(const UpdateData& data);
+    glm::dvec3 position() const;
+    void update(const Time& time);
 
-    glm::dvec3 position(double time);
+    virtual glm::dvec3 position(const Time& time) const = 0;
 
     // Registers a callback that gets called when a significant change has been made that
     // invalidates potentially stored points, for example in trails
@@ -61,11 +61,14 @@ public:
     static documentation::Documentation Documentation();
 
 protected:
-    void notifyObservers();
+    void notifyObservers() const;
+    void requireUpdate();
 
+private:
+    bool _needsUpdate;
+    double _cachedTime;
+    glm::dvec3 _cachedPosition;
     std::function<void()> _onParameterChangeCallback;
-
-    glm::dvec3 _positionValue;
 };
 
 } // namespace openspace