From 6959c971de6ba2541ad879f2a45f0de351003637 Mon Sep 17 00:00:00 2001
From: Death Killer <884052+deathkiller@users.noreply.github.com>
Date: Sun, 28 Jan 2024 23:08:39 +0100
Subject: [PATCH] Improved `Clock`

---
 Sources/nCine/Base/Clock.cpp      | 4 +---
 Sources/nCine/Base/Clock.h        | 9 +--------
 Sources/nCine/Base/FrameTimer.cpp | 6 ++++++
 3 files changed, 8 insertions(+), 11 deletions(-)

diff --git a/Sources/nCine/Base/Clock.cpp b/Sources/nCine/Base/Clock.cpp
index 43b88df7..6cefcece 100644
--- a/Sources/nCine/Base/Clock.cpp
+++ b/Sources/nCine/Base/Clock.cpp
@@ -24,7 +24,7 @@ namespace nCine
 	}
 
 	Clock::Clock()
-		: frequency_(0UL), baseCount_(0ULL)
+		: frequency_(0UL)
 	{
 #if defined(DEATH_TARGET_WINDOWS)
 		LARGE_INTEGER li;
@@ -51,8 +51,6 @@ namespace nCine
 			frequency_ = 1.0e6L;
 		}
 #endif
-
-		baseCount_ = counter();
 	}
 
 	uint64_t Clock::counter() const
diff --git a/Sources/nCine/Base/Clock.h b/Sources/nCine/Base/Clock.h
index 69263d3c..f8760ffa 100644
--- a/Sources/nCine/Base/Clock.h
+++ b/Sources/nCine/Base/Clock.h
@@ -8,9 +8,8 @@ namespace nCine
 	class Clock
 	{
 	public:
-		/// Returns elapsed time in ticks since base time
 		inline uint64_t now() const {
-			return counter() - baseCount_;
+			return counter();
 		}
 
 		/// Returns current value of the counter
@@ -20,10 +19,6 @@ namespace nCine
 		inline uint32_t frequency() const {
 			return frequency_;
 		}
-		/// Retruns the counter value at initialization time
-		inline uint64_t baseCount() const {
-			return baseCount_;
-		}
 
 	private:
 #if defined(DEATH_TARGET_WINDOWS)
@@ -34,8 +29,6 @@ namespace nCine
 
 		/// Counter frequency in counts per second
 		uint32_t frequency_;
-		/// Counter value at initialization time
-		uint64_t baseCount_;
 
 		/// Private constructor
 		Clock();
diff --git a/Sources/nCine/Base/FrameTimer.cpp b/Sources/nCine/Base/FrameTimer.cpp
index ed670d14..a0aef6f5 100644
--- a/Sources/nCine/Base/FrameTimer.cpp
+++ b/Sources/nCine/Base/FrameTimer.cpp
@@ -29,6 +29,12 @@ namespace nCine
 		timeMults_[1] = timeMultLast;
 
 		// Update the FPS average calculation every `avgInterval_` seconds
+		if (frameStart_ < lastAvgUpdate_ || frameStart_ < lastLogUpdate_) {
+			LOGW("Detected time discontinuity, resetting counters");
+			lastAvgUpdate_ = frameStart_;
+			lastLogUpdate_ = frameStart_;
+		}
+
 		const float secsSinceLastAvgUpdate = (frameStart_ - lastAvgUpdate_).seconds();
 		if (averageInterval_ > 0.0f && secsSinceLastAvgUpdate > averageInterval_) {
 			avgFps_ = static_cast<float>(avgNumFrames_) / secsSinceLastAvgUpdate;