Introduction to OpenGL (2) The first demo code of the Red Book

This demo is a bit tricky, the code is incomplete, you have to write this part of LoadShaders by yourself, and I roughly changed it to the following

#include <stdio.h>
#include <string>
#include <vector>
#include <iostream>
using namespace std;

//opengl headers!
#include <glew.h>
#include <glut.h>

#pragma comment(lib,"glew32.lib")
#pragma comment(lib,"glut32.lib")



enum VAO_IDs { Triangles, NumVAOs };
enum Buffer_IDs { ArrayBuffer, NumBuffers };
enum Attrib_IDs { vPosition = 0 };
GLuint VAOs[NumVAOs];
GLuint Buffers[NumBuffers];
const GLuint NumVertices = 6;


GLuint LoadShaders()
{
    //generate shader names
    GLuint vertShader = glCreateShader(GL_VERTEX_SHADER);
    GLuint fragShader = glCreateShader(GL_FRAGMENT_SHADER);

    const char* vertShaderSrc ="#version 450 core \n layout (location = 0)  in vec4 vPosition; void main(){gl_Position = vPosition;}";
    const char* fragShaderSrc ="#version 450 core \n layout (location = 0)  out vec4 fColor; void main(){fColor =  vec4 (255, 0, 0, 255);}";
    GLint result = GL_FALSE;
    int logLength;

    //compile vertex shader
    glShaderSource(vertShader, 1, &vertShaderSrc, NULL);
    glCompileShader(vertShader);
    glGetShaderiv(vertShader, GL_COMPILE_STATUS, &result);
    glGetShaderiv(vertShader, GL_INFO_LOG_LENGTH, &logLength);
    vector<char> vertShaderError(logLength+1);
    glGetShaderInfoLog(vertShader, logLength, NULL, &vertShaderError[0]);
    cout << &vertShaderError[0] << endl;

    //compile fragment shader
    glShaderSource(fragShader, 1, &fragShaderSrc, NULL);
    glCompileShader(fragShader);
    glGetShaderiv(fragShader, GL_COMPILE_STATUS, &result);
    glGetShaderiv(fragShader, GL_INFO_LOG_LENGTH, &logLength);
    vector<char> fragShaderError(logLength+1);
    glGetShaderInfoLog(fragShader, logLength, NULL, &fragShaderError[0]);
    cout << &fragShaderError[0] << endl; 

    //link the program
    GLuint program = glCreateProgram();
    glAttachShader(program, vertShader);
    glAttachShader(program, fragShader);
    glLinkProgram(program);

    glGetProgramiv(program, GL_LINK_STATUS, &result);
    glGetProgramiv(program, GL_INFO_LOG_LENGTH, &logLength);
    vector<char> programError(logLength > 1 ? logLength : 1);
    glGetProgramInfoLog(program, logLength, NULL, &programError[0]);
    cout << &programError[0] << endl;

    glDeleteShader(vertShader);
    glDeleteShader(fragShader);

    return program;
}

#define BUFFER_OFFSET(a) ((void*)(a))


void Init()
{
    static const GLfloat vertices[NumVertices][2] =
    {
        { -0.90, -0.90 }, // Triangle 1
        { 0.85, -0.90 },
        { -0.90, 0.85 },
        { 0.90, -0.85 }, // Triangle 2
        { 0.90, 0.90 },
        { -0.85, 0.90 }
    }; 
    glCreateBuffers(NumBuffers, Buffers);
    glNamedBufferStorage(Buffers[ArrayBuffer]   ,  sizeof(vertices),
        vertices, 0);

    GLuint program = LoadShaders();
    glUseProgram(program);
    glGenVertexArrays(NumVAOs, VAOs);
    glBindVertexArray(VAOs[Triangles]);
    glBindBuffer(GL_ARRAY_BUFFER, Buffers[ArrayBuffer]);
    glVertexAttribPointer(vPosition, 2, GL_FLOAT,
        GL_FALSE, 0, BUFFER_OFFSET(0));
    glEnableVertexAttribArray(vPosition);

}


void display()
{
    static const float color[] = { (float)240/255, (float)240/255, (float)240/255,1.0};
    glClearBufferfv(GL_COLOR, 0, color);

    glBindVertexArray(VAOs[Triangles]);
    glDrawArrays(GL_TRIANGLES, 0, NumVertices);

    glutSwapBuffers();
}



int _tmain(int argc, char* argv[])
{
    glutInit( &argc, argv );                                       //用于初始化GULT库
    glutInitDisplayMode ( GLUT_DEPTH | GLUT_DOUBLE | GLUT_RGBA );  //设置初始显示模式
    glutInitWindowPosition (0,0);                                  //确定窗口的位置
    glutInitWindowSize  ( 900, 500 );                              //设置窗口大小
    glutCreateWindow    ( "OpenGlScreen" );                        //创建一个窗口标题
    glewInit();

    const GLubyte* name = glGetString(GL_VENDOR); //返回负责当前OpenGL实现厂商的名字
    const GLubyte* biaoshifu = glGetString(GL_RENDERER); //返回一个渲染器标识符，通常是个硬件平台
    const GLubyte* OpenGLVersion =glGetString(GL_VERSION); //返回当前OpenGL实现的版本号
    const GLubyte* gluVersion= gluGetString(GLU_VERSION); //返回当前GLU工具库版本
    printf("OpenGL实现厂商的名字：%s\n", name);
    printf("渲染器标识符：%s\n", biaoshifu);
    printf("OOpenGL实现的版本号：%s\n",OpenGLVersion );
    printf("OGLU工具库版本：%s\n", gluVersion);


    Init ();
    //glutFullScreen      ( );          //Put Into Full Screen
    glutDisplayFunc     ( display );    //注册一个绘图函数
    glutReshapeFunc     ( nullptr );    //设置投影的函数
    glutKeyboardFunc    ( nullptr );    //键盘回调函数
    glutSpecialFunc     ( nullptr );    //设置当前窗口的特殊键盘回调。
    glutIdleFunc        ( nullptr );    //程序空闲时调用的函数
    glutMainLoop        ( );            // 进入GLUT事件处理循环

    return 0;
}

success:

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