vkCreateXcbSurfaceKHR

函数原型

VkResult vkCreateXcbSurfaceKHR(
    VkInstance                                  instance,
    const VkXcbSurfaceCreateInfoKHR*            pCreateInfo,
    const VkAllocationCallbacks*                pAllocator,
    VkSurfaceKHR*                               pSurface);

描述

为X11窗口创建VkSurfaceKHR对象。

参数

• instance : 与surface关联的surface。
• pCreateInfo : VkXcbSurfaceCreateInfoKHR 结构体指针，包含创建surface的信息。
• pAllocator : host memory 分配器。
• pSurface : 创建返回的suface句柄。

补充

VkXcbSurfaceCreateInfoKHR 结构体定义：

typedef struct VkXcbSurfaceCreateInfoKHR {
    VkStructureType               sType;
    const void*                   pNext;
    VkXcbSurfaceCreateFlagsKHR    flags;
    xcb_connection_t*             connection;    //xcb connectin
    xcb_window_t                  window;		   //xcb window
} VkXcbSurfaceCreateInfoKHR;

返回值

• VK_SUCCESS : 成功创建surface。
• 其他 : 创建失败。

代码示例

struct sample_info {
    xcb_connection_t *connection;
    xcb_screen_t *screen;
    xcb_window_t window;
    xcb_intern_atom_reply_t *atom_wm_delete_window;
    VkSurfaceKHR surface;
}

void init_connection(struct sample_info &info) {
    const xcb_setup_t *setup;
    xcb_screen_iterator_t iter;
    int scr;

    info.connection = xcb_connect(NULL, &scr);
    if (info.connection == NULL || xcb_connection_has_error(info.connection)) {
        std::cout << "Unable to make an XCB connection\n";
        exit(-1);
    }

    setup = xcb_get_setup(info.connection);
    iter = xcb_setup_roots_iterator(setup);
    while (scr-- > 0) xcb_screen_next(&iter);
    info.screen = iter.data;
}


void init_window(struct sample_info &info) {
    uint32_t value_mask, value_list[32];

    info.window = xcb_generate_id(info.connection);

    value_mask = XCB_CW_BACK_PIXEL | XCB_CW_EVENT_MASK;
    value_list[0] = info.screen->black_pixel;
    value_list[1] = XCB_EVENT_MASK_KEY_RELEASE | XCB_EVENT_MASK_EXPOSURE;

    xcb_create_window(info.connection, XCB_COPY_FROM_PARENT, info.window, info.screen->root, 0, 0, info.width, info.height, 0,
                      XCB_WINDOW_CLASS_INPUT_OUTPUT, info.screen->root_visual, value_mask, value_list);

    /* Magic code that will send notification when window is destroyed */
    xcb_intern_atom_cookie_t cookie = xcb_intern_atom(info.connection, 1, 12, "WM_PROTOCOLS");
    xcb_intern_atom_reply_t *reply = xcb_intern_atom_reply(info.connection, cookie, 0);

    xcb_intern_atom_cookie_t cookie2 = xcb_intern_atom(info.connection, 0, 16, "WM_DELETE_WINDOW");
    info.atom_wm_delete_window = xcb_intern_atom_reply(info.connection, cookie2, 0);

    xcb_change_property(info.connection, XCB_PROP_MODE_REPLACE, info.window, (*reply).atom, 4, 32, 1,
                        &(*info.atom_wm_delete_window).atom);
    free(reply);

    xcb_map_window(info.connection, info.window);

    // Force the x/y coordinates to 100,100 results are identical in consecutive
    // runs
    const uint32_t coords[] = {100, 100};
    xcb_configure_window(info.connection, info.window, XCB_CONFIG_WINDOW_X | XCB_CONFIG_WINDOW_Y, coords);
    xcb_flush(info.connection);

    xcb_generic_event_t *e;
    while ((e = xcb_wait_for_event(info.connection))) {
        if ((e->response_type & ~0x80) == XCB_EXPOSE) break;
    }
}


void main()
{
    struct sample_info info = {};
    init_connection(info);
    init_window(info);

    VkXcbSurfaceCreateInfoKHR createInfo = {};
    createInfo.sType = VK_STRUCTURE_TYPE_XCB_SURFACE_CREATE_INFO_KHR;
    createInfo.pNext = NULL;
    createInfo.connection = info.connection;
    createInfo.window = info.window;
    vkCreateXcbSurfaceKHR(info.inst, &createInfo, NULL, &info.surface);
}