main.cpp

// Include standard headers
#include <stdio.h>
#include <stdlib.h>

// Include GLEW
#include <GL/glew.h>

// Include GLFW
#include <glfw3.h>
GLFWwindow* window;

// Include GLM
#include <glm/glm.hpp>
using namespace glm;

#include <iostream>
#include <chrono>
#include <thread>

int main1(void)
{
	// Initialise GLFW
	if (!glfwInit())
	{
		fprintf(stderr, "Failed to initialize GLFW\n");
		getchar();
		return -1;
	}

	glfwWindowHint(GLFW_SAMPLES, 4);
	glfwWindowHint(GLFW_CONTEXT_VERSION_MAJOR, 3);
	glfwWindowHint(GLFW_CONTEXT_VERSION_MINOR, 3);
	glfwWindowHint(GLFW_OPENGL_FORWARD_COMPAT, GL_TRUE); // To make MacOS happy; should not be needed
	glfwWindowHint(GLFW_OPENGL_PROFILE, GLFW_OPENGL_CORE_PROFILE);

	// Open a window and create its OpenGL context
	window = glfwCreateWindow(1024, 768, "Tutorial 01", NULL, NULL);
	if (window == NULL) {
		fprintf(stderr, "Failed to open GLFW window. If you have an Intel GPU, they are not 3.3 compatible. Try the 2.1 version of the tutorials.\n");
		getchar();
		glfwTerminate();
		return -1;
	}
	glfwMakeContextCurrent(window);

	// Initialize GLEW
	if (glewInit() != GLEW_OK) {
		fprintf(stderr, "Failed to initialize GLEW\n");
		getchar();
		glfwTerminate();
		return -1;
	}

	// Ensure we can capture the escape key being pressed below
	glfwSetInputMode(window, GLFW_STICKY_KEYS, GL_TRUE);
	
	// Dark blue background
	glClearColor(0.0f, 0.0f, 0.4f, 0.0f);

	do {
		std::chrono::time_point<std::chrono::high_resolution_clock> now =
			std::chrono::high_resolution_clock::now();
		std::chrono::high_resolution_clock::duration duration = now.time_since_epoch();
		__int64 startMillis = std::chrono::duration_cast<std::chrono::milliseconds>(duration).count();

		// Clear the screen. It's not mentioned before Tutorial 02, but it can cause flickering, so it's there nonetheless.
		glClear(GL_COLOR_BUFFER_BIT);
		
		// Swap buffers
		glfwSwapBuffers(window);
		glfwPollEvents();

		std::this_thread::sleep_for(std::chrono::milliseconds(500));
		now = std::chrono::high_resolution_clock::now();
		duration = now.time_since_epoch();
		__int64 endMillis = std::chrono::duration_cast<std::chrono::milliseconds>(duration).count();

		std::cout << "Frame duration" << endMillis - startMillis << std::endl;
	} // Check if the ESC key was pressed or the window was closed
	while (glfwGetKey(window, GLFW_KEY_ESCAPE) != GLFW_PRESS &&
		glfwWindowShouldClose(window) == 0);

	// Close OpenGL window and terminate GLFW
	glfwTerminate();

	return 0;
}