VAO 不渲染，OpenGL

Question

我已经尝试获取一个数组对象来渲染到窗口有一段时间了。 GLEW 功能似乎没有运行。结果应该是渲染到输出窗口的三角形。可能是这些功能已被弃用或缺少某些功能。

#include <GL/glew.h>
#include <GLFW/glfw3.h>
#include <iostream>
#include <Vector>
#include <fstream>
#include <string> 
#include <string_view>
#include <windows.h>
#include <winuser.h>
#include <stdio.h>   


using namespace std; 

GLuint vao = 0;
GLuint vbo = 0;

int main(void) {
    if (!glfwInit()) {
        exit(EXIT_FAILURE);
    }
    glfwWindowHint(GLFW_CONTEXT_VERSION_MAJOR, 2);
    glfwWindowHint(GLFW_CONTEXT_VERSION_MINOR, 0);
    GLFWwindow* window = glfwCreateWindow(640, 640, "OpenGL Example", NULL, NULL);
    if (!window) {
        glfwTerminate();
        exit(EXIT_FAILURE);
    }
    glfwMakeContextCurrent(window);
    glfwSwapInterval(1);

    glewInit();
    static const GLfloat g_vertex_buffer_data[] = {
        1.0f, 1.0f, 0.0f,
        1.0f, 1.0f, 0.0f,
        0.0f, 1.0f, 0.0f,
    }; 
    glGenVertexArrays(1, &vao); 
    glBindVertexArray(vao);
    glGenBuffers(1, &vbo);
    glBindBuffer(GL_ARRAY_BUFFER, vbo);
    glBufferData(GL_ARRAY_BUFFER, 9 * sizeof(GLfloat), &g_vertex_buffer_data[0], GL_STATIC_DRAW);
     
     
    //glBindBuffer(GL_ARRAY_BUFFER, 0);


    const float DEG2RAD = 3.14159 / 180; 
    float r = 0.0;
    float g = 0.3;
    float b = 0.6; 
    while (!glfwWindowShouldClose(window)) {
        //Setup View
        float ratio;
        int width, height;
        glfwGetFramebufferSize(window, &width, &height);
        ratio = width / (float)height;
        glViewport(0, 0, width, height);
        glClear(GL_COLOR_BUFFER_BIT);
         
        //Drawing
        glColor3f(r, g, b);
        glEnableClientState(GL_VERTEX_ARRAY);
        glBindBuffer(GL_ARRAY_BUFFER, vbo);
        glVertexPointer(3, GL_FLOAT, 0, &g_vertex_buffer_data[0]);
        glDrawArrays(GL_TRIANGLES, 0, 3); 
        glDisableClientState(GL_VERTEX_ARRAY); 
        //Swap buffer and check for events
        glfwSwapBuffers(window);
        glfwPollEvents();
    }

    glfwDestroyWindow(window);
    glfwTerminate;
    exit(EXIT_SUCCESS);
}

应将三角形渲染到窗口。

Answer 1

VAO 自 OpenGL 3.0 版起就已纳入标准，因此它们不在 OpenGL 2 版中。另请参阅顶点数组对象。一个选择可能是使用 OpenGL 扩展

GL_ARB_vertex_array_object

。