vkQueuePresentKHR returned None

[sunbearc22]

Hi realitix, Is the function vkQueuePresentKHR suppose to return None or VkResult? I was expecting the latter.

I am attempting the resizeable window tutorial of Vulkan Tutorial. I noticed that vkQueuePresentKHR returns None.

        result = self.fnp['vkQueuePresentKHR'](self.present_queue, presentInfo)
        print('result = ',result)

        if result == VK_ERROR_OUT_OF_DATE_KHR or result == VK_SUBOPTIMAL_KHR:
            logging.error("Needs to recreate swapchain.!")
            self._recreateSwapChain()
        elif result != VK_SUCCESS:
            logging.error("Failed to present swapchain image!")

        vkQueueWaitIdle(self.present_queue)

Output:

result =  None
2017-10-18 16:21:19,156 vulkanbase_v3_recreateSwapChain._drawFrame                     +1625 : ERROR    Failed to present swapchain image!

[realitix]

Hello @sunbearc22, it's strange because this function can't return None. Can you show how you initialize

self.fnp['vkQueuePresentKHR']

[sunbearc22]

Yes. I just uploaded my codes https://github.com/sunbearc22/vulkan_examples/blob/master/HelloTriangle/vulkanbase_v3_recreateSwapChain.py#L208. version 3 codes.

[realitix]

My last comment was wrong. It's normal that it returns None. All functions return None with the wrapper. To catch the return value, you must use the exception system.