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Code is below. When the program runs, it generates a more or less correct image, but there are some graphical glitches. Here are some images:123. Any ideas on what could be causing this? The weirdest part is that the issue appears to form on triangles, even though the image is being drawn with polygons (quads). 

void buildList() {
    cubelist = glGenLists(1);
    glNewList(cubelist,GL_COMPILE);

    // Multi-colored side - FRONT
    glBegin(GL_POLYGON);
    glColor3b(0,0,0);
    glVertex3f( -0.5, -0.5, -0.5);
    glVertex3f( -0.5,  0.5, -0.5);
    glVertex3f(  0.5,  0.5, -0.5);
    glVertex3f(  0.5, -0.5, -0.5);
    // Black side - BACK
    glBegin(GL_POLYGON);
    glColor3b(0,0,0);
    glVertex3f(  0.5, -0.5, 0.5 );
    glVertex3f(  0.5,  0.5, 0.5 );
    glVertex3f( -0.5,  0.5, 0.5 );
    glVertex3f( -0.5, -0.5, 0.5 );
    glEnd();

    // Purple side - RIGHT
    glBegin(GL_POLYGON);
    glColor3f(  1.0,  0.0,  1.0 );
    glVertex3f( 0.5, -0.5, -0.5 );
    glVertex3f( 0.5,  0.5, -0.5 );
    glVertex3f( 0.5,  0.5,  0.5 );
    glVertex3f( 0.5, -0.5,  0.5 );
    glEnd();

    // Green side - LEFT
    glBegin(GL_POLYGON);
    glColor3f(   0.0,  1.0,  0.0 );
    glVertex3f( -0.5, -0.5,  0.5 );
    glVertex3f( -0.5,  0.5,  0.5 );
    glVertex3f( -0.5,  0.5, -0.5 );
    glVertex3f( -0.5, -0.5, -0.5 );
    glEnd();

    // Blue side - TOP
    glBegin(GL_POLYGON);
    glColor3f(   0.0,  0.0,  1.0 );
    glVertex3f(  0.5,  0.5,  0.5 );
    glVertex3f(  0.5,  0.5, -0.5 );
    glVertex3f( -0.5,  0.5, -0.5 );
    glVertex3f( -0.5,  0.5,  0.5 );
    glEnd();

    // Red side - BOTTOM
    glBegin(GL_POLYGON);
    glColor3f(   1.0,  0.0,  0.0 );
    glVertex3f(  0.5, -0.5, -0.5 );
    glVertex3f(  0.5, -0.5,  0.5 );
    glVertex3f( -0.5, -0.5,  0.5 );
    glVertex3f( -0.5, -0.5, -0.5 );
    glEnd();
    glEndList();
}

void setupGL() {
    glClearColor(1, 1, 1, 0);
    glEnable(GL_DEPTH_CLAMP);
    glEnable(GL_DEPTH_TEST);
    glDepthFunc(GL_LESS);
    glCullFace(GL_FRONT_AND_BACK);
}

int main(int, char const**)
{
    sf::Window window(sf::VideoMode(1600, 1200), "OpenGL", sf::Style::Default, sf::ContextSettings(32));
    window.setVerticalSyncEnabled(true);
    //initWorld();
    setupGL();
    buildList();

    while (running)
    {

        glClear(GL_COLOR_BUFFER_BIT | GL_DEPTH_BUFFER_BIT);
        // Process events
        sf::Event event;
        handleInput(window);
        while (window.pollEvent(event))
        {
            // Close window: exit
            if (event.type == sf::Event::Closed) {
                running = false;
            }

            // Escape pressed: exit
            if (event.type == sf::Event::KeyPressed && event.key.code == sf::Keyboard::Escape) {
                running = false;
            }
        }

        glCallList(cubelist);

        // Update the window (c is a "Camera" object that just sets the perspective.   I can provide code if necessary)
        c.draw();
        window.display();
    }

    return EXIT_SUCCESS;
}

EDIT: So changing the GL_POLYGONS statements to GL_QUADS seemed to fix the problem, but I'm still somewhat curious as to why.

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1 回答 1

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您的 firstglBegin没有匹配glEnd，这会导致所有其他glBegins 被忽略，直到 next glEnd。这意味着正面泄漏到背面。

也就是说，立即模式和相关的 displayList 已被弃用，而是查看 VBO 来存储顶点数据。

于 2015-01-29T16:26:41.950 回答