+ int imgid;
+ VkCommandBuffer cmdbuf;
+
+ /* get the next image from the swap chain */
+ imgid = vk_next_image(sem_getimg);
+ cmdbuf = vk_get_cmdbuf(imgid);
+
+ /* TODO record */
+
+ /* submit the command buffer, wait for one semaphore, signal another */
+ vk_submit(cmdbuf, sem_getimg, sem_draw);
+
+ /* swap buffers after drawing is finished */
+ vk_present(sem_draw);