现代opengl和传统opengl的简单代码对比

传统OpenGL（固定管线）的代码：

#include <GL/glut.h>

void display() {
    glClear(GL_COLOR_BUFFER_BIT);
    glColor3f(1.0, 0.0, 0.0);
    glBegin(GL_TRIANGLES);
    glVertex3f(-0.5, -0.5, 0);
    glVertex3f(0.5, -0.5, 0);
    glVertex3f(0, 0.5, 0);
    glEnd();
    glFlush();
}

int main(int argc, char** argv) {
    glutInit(&argc, argv);
    glutCreateWindow("OpenGL Test");
    glutDisplayFunc(display);
    glutMainLoop();
    return 0;
}

现代OpenGL（可编程管线）的代码：

#include <GL/glew.h>
#include <GLFW/glfw3.h>

int main() {
    glfwInit();
    GLFWwindow* window = glfwCreateWindow(640, 480, "OpenGL Test", NULL, NULL);
    glfwMakeContextCurrent(window);
    glewInit();

    float vertices[] = {
        -0.5, -0.5, 0,
        0.5, -0.5, 0,
        0, 0.5, 0
    };

    GLuint VAO, VBO;
    glGenVertexArrays(1, &VAO);
    glGenBuffers(1, &VBO);

    glBindVertexArray(VAO);

    glBindBuffer(GL_ARRAY_BUFFER, VBO);
    glBufferData(GL_ARRAY_BUFFER, sizeof(vertices), vertices, GL_STATIC_DRAW);

    glVertexAttribPointer(0, 3, GL_FLOAT, GL_FALSE, 3 * sizeof(float), (void*)0);
    glEnableVertexAttribArray(0);

    glBindBuffer(GL_ARRAY_BUFFER, 0);
    glBindVertexArray(0);

    while (!glfwWindowShouldClose(window)) {
        glClear(GL_COLOR_BUFFER_BIT);

        glBindVertexArray(VAO);
        glDrawArrays(GL_TRIANGLES, 0, 3);
        glBindVertexArray(0);

        glfwSwapBuffers(window);
        glfwPollEvents();
    }

    glfwTerminate();
    return 0;
}

可以看到，现代OpenGL的代码比传统OpenGL的代码更加复杂和冗长，但同时也更加灵活和可扩展。传统OpenGL的代码使用了固定管线，只能进行简单的图形渲染，而现代OpenGL的代码使用了可编程管线，可以实现更加复杂的图形渲染和计算。