1 files changed, 58 insertions, 0 deletions
diff --git a/mwe/gameloop/src/timer.cpp b/mwe/gameloop/src/timer.cpp
new file mode 100644
index 0000000..61e144d
--- /dev/null
+++ b/mwe/gameloop/src/timer.cpp
@@ -0,0 +1,58 @@
+#include "timer.h"
+
+// Constructor (private)
+LoopTimer::LoopTimer() {}
+
+// Get the singleton instance of the timer
+LoopTimer & LoopTimer::getInstance() {
+	static LoopTimer instance;
+	return instance;
+}
+
+// Start the timer (initialize frame time)
+void LoopTimer::start() {
+	lastFrameTime = SDL_GetTicks64();
+	elapsedTime = 0;
+	elapsedFixedTime = 0;
+	deltaTime = 0;
+}
+
+// Update the timer, calculate deltaTime
+void LoopTimer::update() {
+	uint64_t currentFrameTime = SDL_GetTicks64();
+	deltaTime
+		= (currentFrameTime - lastFrameTime) / 1000.0; // Convert to seconds
+
+	if (deltaTime > maximumDeltaTime) {
+		deltaTime = maximumDeltaTime;
+	}
+
+	elapsedTime += deltaTime;
+	lastFrameTime = currentFrameTime;
+}
+
+double LoopTimer::getDeltaTime() const { return deltaTime; }
+int LoopTimer::getCurrentTime() const { return SDL_GetTicks(); }
+
+void LoopTimer::advanceFixedUpdate() { elapsedFixedTime += fixedDeltaTime; }
+
+double LoopTimer::getFixedDeltaTime() const { return fixedDeltaTime; }
+
+void LoopTimer::setFPS(int FPS) {
+	this->FPS = FPS;
+	frameTargetTime = 1.0 / FPS;
+}
+
+int LoopTimer::getFPS() const { return FPS; }
+
+void LoopTimer::enforceFrameRate() {
+	uint64_t currentFrameTime = SDL_GetTicks64();
+	double frameDuration = (currentFrameTime - lastFrameTime) / 1000.0;
+
+	if (frameDuration < frameTargetTime) {
+		uint32_t delayTime
+			= (uint32_t) ((frameTargetTime - frameDuration) * 1000.0);
+		SDL_Delay(delayTime);
+	}
+}
+double LoopTimer::getLag() const { return elapsedTime - elapsedFixedTime; }