added scaled fixed delta time

4 files changed, 60 insertions, 13 deletions

diff --git a/src/crepe/api/LoopManager.cpp b/src/crepe/api/LoopManager.cpp
index 4d97e16..d17aee1 100644
--- a/src/crepe/api/LoopManager.cpp
+++ b/src/crepe/api/LoopManager.cpp
@@ -48,7 +48,7 @@ void LoopManager::loop() {
 	while (game_running) {
 		this->loop_timer.update();
 
-		while (this->loop_timer.get_lag() >= this->loop_timer.get_fixed_delta_time()) {
+		while (this->loop_timer.get_lag() >= this->loop_timer.get_scaled_fixed_delta_time()) {
 			this->process_input();
 			this->fixed_update();
 			this->loop_timer.advance_fixed_update();
diff --git a/src/crepe/manager/LoopTimerManager.cpp b/src/crepe/manager/LoopTimerManager.cpp
index e30b90d..5d4545f 100644
--- a/src/crepe/manager/LoopTimerManager.cpp
+++ b/src/crepe/manager/LoopTimerManager.cpp
@@ -82,3 +82,10 @@ void LoopTimerManager::enforce_frame_rate() {
 double LoopTimerManager::get_lag() const {
 	return (this->elapsed_time - this->elapsed_fixed_time).count();
 }
+double LoopTimerManager::get_scaled_fixed_delta_time() const{
+	return this->fixed_delta_time.count() * this->time_scale;
+}
+void LoopTimerManager::set_fixed_delta_time(int seconds) {
+    this->fixed_delta_time = std::chrono::duration<double>(seconds);
+}
+
diff --git a/src/crepe/manager/LoopTimerManager.h b/src/crepe/manager/LoopTimerManager.h
index cd05bf2..8fb4461 100644
--- a/src/crepe/manager/LoopTimerManager.h
+++ b/src/crepe/manager/LoopTimerManager.h
@@ -65,6 +65,35 @@ public:
 	 */
 	void set_time_scale(double time_scale);
 
+	/**
+	 * \brief Get the scaled fixed delta time om seconds.
+	 *
+	 * The fixed delta time is used for operations that require uniform time steps, 
+	 * such as physics calculations, and is scaled by the current time scale.
+	 *
+	 * \return The fixed delta time, scaled by time scale, in seconds.
+	 */
+	double get_scaled_fixed_delta_time() const;
+
+	/**
+	 * \brief Get the fixed delta time in seconds without scaling by the time scale.
+	 *
+	 * This value is used in the LoopManager to determine how many times 
+	 * the fixed_update should be called within a given interval.
+	 *
+	 * \return The unscaled fixed delta time in seconds.
+	 */
+	double get_fixed_delta_time() const;
+
+	/**
+	 * \brief Set the fixed_delta_time in seconds.
+	 * 
+	 * \param ms fixed_delta_time in seconds.
+	 * 
+	 * The fixed_delta_time value is used to determine how many times per second the fixed_update and process_input functions are called.
+	 */
+	void set_fixed_delta_time(int seconds);
+
 private:
 	friend class LoopManager;
 
@@ -81,17 +110,6 @@ private:
 	 * necessary.
 	 */
 	void enforce_frame_rate();
-
-	/**
-	 * \brief Get the fixed delta time for consistent updates.
-	 *
-	 * Fixed delta time is used for operations that require uniform time steps, such as physics
-	 * calculations.
-	 *
-	 * \return Fixed delta time in seconds.
-	 */
-	double get_fixed_delta_time() const;
-
 	/**
 	 * \brief Get the accumulated lag in the game loop.
 	 *
@@ -123,7 +141,7 @@ private:
 	int target_fps = 50;
 	//! Actual frames per second
 	int actual_fps = 0;
-	//! time scale for speeding up or slowing down the game (0 = pause, < 1 = slow down, 1 = normal speed, > 1 = speed up)
+	//! Time scale for speeding up or slowing down the game (0 = pause, < 1 = slow down, 1 = normal speed, > 1 = speed up)
 	double time_scale = 1;
 	//! Maximum delta time in seconds to avoid large jumps
 	std::chrono::duration<double> maximum_delta_time{0.25};
diff --git a/src/test/LoopManagerTest.cpp b/src/test/LoopManagerTest.cpp
index f73605e..55ccbb3 100644
--- a/src/test/LoopManagerTest.cpp
+++ b/src/test/LoopManagerTest.cpp
@@ -45,6 +45,28 @@ TEST_F(LoopManagerTest, FixedUpdate) {
 
 	// Test finished
 }
+TEST_F(LoopManagerTest, ScaledFixedUpdate) {
+	// Arrange
+	test_loop.loop_timer.set_target_fps(60);
+
+	// Set expectations for the mock calls
+	EXPECT_CALL(test_loop, render).Times(::testing::Exactly(60));
+	EXPECT_CALL(test_loop, update).Times(::testing::Exactly(60));
+	EXPECT_CALL(test_loop, fixed_update).Times(::testing::Exactly(50));
+
+	// Start the loop in a separate thread
+	std::thread loop_thread([&]() { test_loop.start(); });
+
+	// Let the loop run for exactly 1 second
+	std::this_thread::sleep_for(std::chrono::seconds(1));
+
+	// Stop the game loop
+	test_loop.game_running = false;
+	// Wait for the loop thread to finish
+	loop_thread.join();
+
+	// Test finished
+}
 TEST_F(LoopManagerTest, ShutDown) {
 	// Arrange
 	test_loop.loop_timer.set_target_fps(60);