ImGuiIO& io = ImGui::GetIO(); (void)io;

//允許停靠
io.ConfigFlags |= ImGuiConfigFlags_DockingEnable;
//視口設置無裝飾
io.ConfigFlags |= ImGuiViewportFlags_NoDecoration;
//允許視口停靠
io.ConfigFlags |= ImGuiConfigFlags_ViewportsEnable;
//停靠於背景
io.ConfigFlags |= ImGuiCol_DockingEmptyBg;

ImGui::DockSpaceOverViewport();

if (io.ConfigFlags & ImGuiConfigFlags_ViewportsEnable)
{
    //當窗口拉出窗口範圍 創建子窗口
    GLFWwindow* backup_current_context = glfwGetCurrentContext();
    ImGui::UpdatePlatformWindows();
    ImGui::RenderPlatformWindowsDefault();
    glfwMakeContextCurrent(backup_current_context);
}