reshaping the modelloader class to suit the overall design of openspace

include/openspace/util/constants.h

@@ -67,17 +67,22 @@ namespace renderable {
 } // namespace renderable
 
 namespace renderableplanet {
-    const std::string keyGeometry = "Geometry";
 	const std::string keyFrame = "Frame";
+	const std::string keyGeometry = "Geometry";
 } // namespace renderableplanet
 
 namespace planetgeometry {
 	const std::string keyType = "Type";
 } // namespace planetgeometry
 
-namespace renderablewavefrontobject {
+namespace renderablemodel {
+	const std::string keyGeometry = "Geometry";
+} // namespace renderablemodel
+
+namespace modelgeometry {
+	const std::string keyType = "Type";
 	const std::string keyObjFile = "ObjFile";
-} // namespace renderableplanet
+} // namespace modelgeometry
 
 namespace renderablestars {
 	const std::string keySpeckFile = "SpeckFile";

include/openspace/util/time.h

@@ -134,6 +134,18 @@ public:
 	 */
 	double advanceTime(double tickTime);
 
+	/**
+	* Retreats the simulation time using the deltaTime() and the <code>tickTime</code>.
+	* The deltaTime() is the number of simulation seconds that pass for each real-time
+	* second. <code>tickTime</code> is the number of real-time seconds that passed since
+	* the last call to this method. If this method is called in the render loop, the
+	* <code>tickTime</code> should be equivalent to the frame time.
+	* \param tickTime The number of real-time seconds that passed since the last call
+	* to this method
+	* \return The new time value after retreating the time
+	*/
+	double retreatTime(double tickTime);
+
 	/**
 	 * Returns the Lua library that contains all Lua functions available to change the
 	 * current time, retrieve the current time etc. The functions contained are