1 files changed, 81 insertions, 0 deletions
diff --git a/src/crepe/api/LoopTimer.h b/src/crepe/api/LoopTimer.h
new file mode 100644
index 0000000..5b7d3f2
--- /dev/null
+++ b/src/crepe/api/LoopTimer.h
@@ -0,0 +1,81 @@
+#pragma once
+
+#include <cstdint>
+
+namespace crepe{
+class LoopTimer {
+public:
+/**
+ * \brief Get the singleton instance of LoopTimer.
+ *
+ * \return A reference to the LoopTimer instance.
+ */
+static LoopTimer& get_instance();
+
+/**
+ * \brief Get the current delta time for the current frame.
+ *
+ * \return Delta time in seconds since the last frame.
+ */
+double get_delta_time() const;
+
+/**
+ * \brief Get the current game time.
+ *
+ * \note The current game time may vary from the real-world elapsed time.
+ * It is the cumulative sum of each frame's delta time.
+ *
+ * \return Elapsed game time in milliseconds.
+ */
+int get_current_time() const;
+
+/**
+ * \brief Set the target frames per second (FPS).
+ *
+ * \param fps The number of frames that should be rendered per second.
+ */
+void set_fps(int fps);
+
+/**
+ * \brief Get the current frames per second (FPS).
+ *
+ * \return Current FPS.
+ */
+int get_fps() const;
+
+/**
+ * \brief Get the current game scale.
+ *
+ * \return The current game scale, where 0 = paused, 1 = normal speed, and values > 1 speed up the game.
+ */
+double get_game_scale() const;
+
+/**
+ * \brief Set the game scale.
+ *
+ * \param game_scale The desired game scale (0 = pause, 1 = normal speed, > 1 = speed up).
+ */
+void set_game_scale(double game_scale);
+
+private:
+friend class LoopManager;
+void start();
+void enforce_frame_rate();
+double get_fixed_delta_time() const;
+double get_lag() const;
+LoopTimer();
+void update();
+void advance_fixed_update();
+private:
+int fps = 50;                       ///< Current frames per second
+double game_scale = 1;              ///< Current game scale
+double maximum_delta_time = 0.25;   ///< Maximum delta time to avoid large jumps
+double delta_time = 0;              ///< Delta time for the current frame
+double frame_target_time = 1.0 / fps; ///< Target time per frame in seconds
+double fixed_delta_time = 0.02;     ///< Fixed delta time for fixed updates
+double elapsed_time = 0;             ///< Total elapsed game time
+double elapsed_fixed_time = 0;      ///< Total elapsed time for fixed updates
+uint64_t last_frame_time = 0;       ///< Time of the last frame
+};
+
+} // namespace crepe