如何创建居中的 GLFW window？

Question

我正在寻找

的 SDL 等价物

gWindow = SDL_CreateWindow( "SDL window", 
            SDL_WINDOWPOS_CENTERED, SDL_WINDOWPOS_CENTERED, 
            WINDOW_WIDTH, WINDOW_HEIGHT, windowFlags );

GLFW。我可以在使用以下代码创建 glfw window 后将其居中，但是，一瞬间，window 显示为非居中。所以看起来不太流畅

    // init glfw
    if (!initGLFW())
    {
        return -1;
    }

    // create main window
    int count;
    int windowWidth, windowHeight;
    int monitorX, monitorY;
    
    GLFWwindow* gWindow;
    GLFWmonitor** monitors = glfwGetMonitors(&count);
    const GLFWvidmode* videoMode = glfwGetVideoMode(monitors[0]);
    // width: 75% of the screen
    windowWidth = videoMode->width / 1.5;
    // Aspect ratio 16 to 9
    windowHeight = windowWidth / 16 * 9;
    
    glfwGetMonitorPos(monitors[0], &monitorX, &monitorY);

    gWindow = glfwCreateWindow(windowWidth, windowHeight, "Engine v" ENGINE_VERSION, NULL, NULL);
    if (!gWindow)
    {
        glfwTerminate();
        std::cout << "Failed to create main window" << std::endl;
        return -1;
    }

    glfwSetWindowPos(gWindow,
                     monitorX + (videoMode->width - windowWidth) / 2,
                     monitorY + (videoMode->height - windowHeight) / 2);

Answer 1

来自documentation：

By default, newly created windows use the placement recommended by the window system. To create the window at a specific position, make it initially invisible using the GLFW_VISIBLE window hint, set its position and then show it.

例子

使用上面的代码，您可以在 glfwCreateWindow 之前添加对 glfwWindowHint 的调用，如下所示：

glfwWindowHint(GLFW_VISIBLE, GLFW_FALSE);

一旦您将 window 定位到您想要的位置，就可以像这样调用 glfwShowWindow：

glfwShowWindow(gWindow);

根据您的用例，在创建 window 后使用 glfwDefaultWindowHints 重置 window 提示可能也是明智的，以确保将来 window 创建未修改。

将所有这些放在一起，我有类似的东西：

if (!glfwInit())
{   
    return -1; 
}   

int count;
int windowWidth, windowHeight;
int monitorX, monitorY;
    
GLFWwindow* gWindow;
GLFWmonitor** monitors = glfwGetMonitors(&count);
const GLFWvidmode* videoMode = glfwGetVideoMode(monitors[0]);
windowWidth = videoMode->width / 1.5;
windowHeight = windowWidth / 16 * 9;
    
glfwGetMonitorPos(monitors[0], &monitorX, &monitorY);

// (1).  Set the visibility window hint to false for subsequent window creation
glfwWindowHint(GLFW_VISIBLE, GLFW_FALSE);

gWindow = glfwCreateWindow(windowWidth, windowHeight, "Engine v", NULL, NULL);
if (!gWindow)
{   
    glfwTerminate();
    std::cout << "Failed to create main window" << std::endl;
    return -1; 
}   

// (2).  Reset the window hints to default
glfwDefaultWindowHints();

glfwSetWindowPos(gWindow,
                 monitorX + (videoMode->width - windowWidth) / 2,
                 monitorY + (videoMode->height - windowHeight) / 2); 

// (3).  Show the window
glfwShowWindow(gWindow);

如何创建居中的 GLFW window？

How do I create a centered GLFW window?

c++

glfw

例子