From 4a57bb1357128868259b63d7a3775e179af8cb68 Mon Sep 17 00:00:00 2001
From: Amy Retzerau <amy.retzerau@gmail.com>
Date: Wed, 3 Sep 2025 13:55:51 +0200
Subject: [PATCH] feat: added FPS counter to terminal

---
 PerformanceAnalyser.hpp | 40 ++++++++++++++++++++++++++++++++++++++++
 main.cpp                | 14 +++++++++++++-
 2 files changed, 53 insertions(+), 1 deletion(-)
 create mode 100644 PerformanceAnalyser.hpp

diff --git a/PerformanceAnalyser.hpp b/PerformanceAnalyser.hpp
new file mode 100644
index 0000000..ac8fa76
--- /dev/null
+++ b/PerformanceAnalyser.hpp
@@ -0,0 +1,40 @@
+#include <GL/glew.h>
+#include <cmath>
+#include <iostream>
+
+class PerformanceAnalyser {
+  private:
+    double lastFrameTime = 0;
+    int frameCount = 0;
+    double timeAcc = 0;
+    double lastFps = 0;
+
+  public:
+    PerformanceAnalyser(int framesToAcc = 10, bool autoPrint = true)
+        : framesToAcc(framesToAcc), autoPrint(autoPrint) {};
+
+    int framesToAcc;
+    bool autoPrint;
+
+    int getFPS() { return lastFps; }
+
+    void update(float time) {
+
+        timeAcc += (time - lastFrameTime);
+        lastFrameTime = time;
+        frameCount++;
+
+        if (frameCount == framesToAcc) {
+
+            lastFps = double(framesToAcc) / timeAcc;
+
+            if (autoPrint) {
+                std::cout << "Fps: " << std::round(lastFps * 10.0) * 0.1 << "\n"
+                          << std::flush;
+            }
+
+            frameCount = 0;
+            timeAcc = 0;
+        }
+    }
+};
diff --git a/main.cpp b/main.cpp
index c4f93fb..7303e76 100644
--- a/main.cpp
+++ b/main.cpp
@@ -1,7 +1,9 @@
 #include "FullScreenQuad.hpp"
+#include "PerformanceAnalyser.hpp"
 #include <GL/glew.h>
 #include <GLFW/glfw3.h>
 #include <cstdio>
+#include <iostream>
 
 const char *vertexShaderSource =
 #include "fsq.glsl"
@@ -75,6 +77,8 @@ void framebuffer_size_callback(GLFWwindow *window, int width, int height) {
 }
 
 int main(int argc, char **argv) {
+    std::cout << "test";
+    std::cout << std::flush;
 
     GLFWwindow *window;
 
@@ -104,7 +108,15 @@ int main(int argc, char **argv) {
 
     FullScreenQuad fsq{};
 
+    PerformanceAnalyser perf{};
+
+    double time = glfwGetTime();
+
     while (!glfwWindowShouldClose(window)) {
+
+        time = glfwGetTime();
+        perf.update(time);
+
         processInput(window);
         /* Render here */
 
@@ -116,7 +128,7 @@ int main(int argc, char **argv) {
         int aspectLocation = glGetUniformLocation(shaderProgram, "aspect");
         glUniform1f(aspectLocation, aspect);
         int timeLocation = glGetUniformLocation(shaderProgram, "t");
-        glUniform1f(timeLocation, 2. * glfwGetTime());
+        glUniform1f(timeLocation, 2. * time);
 
         glBindVertexArray(fsq.getVAO());
         glDrawArrays(GL_TRIANGLES, 0, 6);