Make getTime() relative to first invocation

src/modules/timer/Timer.cpp

@@ -123,7 +123,7 @@ double Timer::getTimerPeriod()
 	return 0;
 }
 
-double Timer::getTime()
+double Timer::getTimeAbsolute()
 {
 	// The timer period (reciprocal of the frequency.)
 	static const double timerPeriod = getTimerPeriod();
@@ -156,5 +156,11 @@ double Timer::getTime()
 #endif
 }
 
+double Timer::getTime()
+{
+	static const double start = getTimeAbsolute();
+	return getTimeAbsolute() - start;
+}
+
 } // timer
 } // love

src/modules/timer/Timer.h

@@ -72,9 +72,10 @@ public:
 	double getAverageDelta() const;
 
 	/**
-	 * Gets the amount of time passed since an unspecified time. Useful for
-	 * profiling code or measuring intervals. The time is microsecond-precise,
-	 * and increases monotonically.
+	 * Gets the amount of time in seconds passed since its first invocation
+	 * (which happens as part of Timer::step at the start of love.run).
+	 * Useful for profiling code or measuring intervals.
+	 * The time is microsecond-precise, and increases monotonically.
 	 * @return The time (in seconds)
 	 **/
 	static double getTime();
@@ -102,6 +103,9 @@ private:
 	// Returns the timer period on some platforms.
 	static double getTimerPeriod();
 
+	// Like getTime, but relative to an unspecified time.
+	static double getTimeAbsolute();
+
 }; // Timer
 
 } // timer