openglwindow

simplegl.cpp

// set Library Search Paths for project
// set Frameworks glfw glew opengl
// set header include serach path
// Signing&Capabilities Disable Library Validation
// #define GL_SILENCE_DEPRECATION

#ifdef __APPLE__
#define GL_SILENCE_DEPRECATION
#endif

#include <stdio.h>
#include <stdlib.h>
#include <GLFW/glfw3.h>

static void error_callback(int error, const char *description)
{
    fputs(description, stderr);
}
static void key_callback(GLFWwindow *window, int key, int scancode, int action, int mods)
{
    if (key == GLFW_KEY_ESCAPE && action == GLFW_PRESS)
        glfwSetWindowShouldClose(window, GL_TRUE);
}

int mWidth = 800;
int mHeight = 600;

int main(void)
{
    printf("Hello OpenGL\n");
    // Load GLFW and Create a Window
    glfwInit();
    glfwWindowHint(GLFW_CONTEXT_VERSION_MAJOR, 3);
    glfwWindowHint(GLFW_CONTEXT_VERSION_MINOR, 2);
    glfwWindowHint(GLFW_OPENGL_PROFILE, GLFW_OPENGL_CORE_PROFILE);
    glfwWindowHint(GLFW_OPENGL_FORWARD_COMPAT, GL_TRUE);
    glfwWindowHint(GLFW_RESIZABLE, GL_FALSE);
    auto mWindow = glfwCreateWindow(mWidth, mHeight, "OpenGL Kun", nullptr, nullptr);
    
    // Check for Valid Context
    if (mWindow == nullptr) {
        fprintf(stderr, "Failed to Create OpenGL Context");
        return EXIT_FAILURE;
    }
    
    // Create OpenGL Context
    glfwMakeContextCurrent(mWindow);
    // Set KeyCallBack
    glfwSetKeyCallback(mWindow, key_callback);
    
    fprintf(stderr, "OpenGL %s\n", glGetString(GL_VERSION));
    
    // Rendering Loop
    while (glfwWindowShouldClose(mWindow) == false)
    {
        // Background Fill Color
        glClearColor(0.25f, 0.25f, 0.25f, 1.0f);
        glClear(GL_COLOR_BUFFER_BIT);
        
        // Flip Buffers and Draw
        glfwSwapBuffers(mWindow);
        glfwPollEvents();
    }
    glfwTerminate();
    return EXIT_SUCCESS;
}