Remove noise from timeutils.cpp

src/scene.cpp

@@ -193,6 +193,7 @@ void step_scene(double timeDelta) {
     lightNode[1]->rotation.z -= timeDelta;
     //lightNode[1]->position.z = 80 + 40*glm::sin(5 * lightNode[1]->rotation.z);
     if(carNode) carNode->rotation.z += timeDelta;
+    if(treeNode) treeNode->rotation.z += timeDelta;
 
     /*
     if (glfwGetMouseButton(window, GLFW_MOUSE_BUTTON_1)) {

src/utilities/timeutils.cpp

@@ -1,23 +1,19 @@
 #include <chrono>
 #include "timeutils.h"
 
-// In order to be able to calculate when the getTimeDeltaSeconds() function was last called, we need to know the point in time when that happened. This requires us to keep hold of that point in time.
-// We initialise this value to the time at the start of the program.
-static std::chrono::steady_clock::time_point _previousTimePoint = std::chrono::steady_clock::now();
 
 // Calculates the elapsed time since the previous time this function was called.
 double getTimeDeltaSeconds() {
-	// Determine the current time
-	std::chrono::steady_clock::time_point currentTime = std::chrono::steady_clock::now();
+	static std::chrono::steady_clock::time_point _prev
+		= std::chrono::steady_clock::now();
 	
-	// Calculate the number of nanoseconds that elapsed since the previous call to this function
-	long long timeDelta = std::chrono::duration_cast<std::chrono::nanoseconds>(currentTime - _previousTimePoint).count();
-	// Convert the time delta in nanoseconds to seconds
-	double timeDeltaSeconds = (double)timeDelta / 1000000000.0;
+	std::chrono::steady_clock::time_point now
+		= std::chrono::steady_clock::now();
 
-	// Store the previously measured current time
-	_previousTimePoint = currentTime;
+	// nanoseconds delta
+	long long td = std::chrono::duration_cast<std::chrono::nanoseconds>(now - _prev).count();
 	
-	// Return the calculated time delta in seconds
-	return timeDeltaSeconds;
+	_prev = now;
+
+	return ((double)td) / 1000000000.0; // return as seconds
 }