Function VulkanBeginFrame

engine/graphics/src/vulkan/graphics_vulkan.cpp:1740–1837

    }

    static void VulkanBeginFrame(HContext _context)
    {
        VulkanContext* context = (VulkanContext*) _context;
        NativeBeginFrame(_context);

        VkDevice vk_device = context->m_LogicalDevice.m_Device;
        uint32_t frameInFlight = context->m_CurrentFrameInFlight;
        FrameResource& currentFrame = context->m_FrameResources[frameInFlight];

        // Wait for GPU to finish work for this frame-in-flight
        vkWaitForFences(vk_device, 1, &currentFrame.m_SubmitFence, VK_TRUE, UINT64_MAX);

        // Acquire next swap chain image
        VkResult res = context->m_SwapChain->Advance(vk_device, currentFrame.m_ImageAvailable);
        if (res != VK_SUCCESS)
        {
            if (res == VK_ERROR_OUT_OF_DATE_KHR)
            {
                context->m_WindowWidth  = dmPlatform::GetWindowWidth(context->m_BaseContext.m_Window);
                context->m_WindowHeight = dmPlatform::GetWindowHeight(context->m_BaseContext.m_Window);
                SwapChainChanged(context, &context->m_WindowWidth, &context->m_WindowHeight, 0, 0);
                res = context->m_SwapChain->Advance(vk_device, currentFrame.m_ImageAvailable);
                CHECK_VK_ERROR(res);
            }
            else if (res == VK_SUBOPTIMAL_KHR)
            {
                // Presenting the swap chain will still work but not optimally, but we should still notify.
                dmLogOnceWarning("Vulkan swapchain is out of date, reason: VK_SUBOPTIMAL_KHR.");
            }
            else
            {
                dmLogOnceError("Vulkan swapchain is out of date, reason: %s.", VkResultToStr(res));
                return;
            }
        }

        // Only reset after a successful acquire. If we bail before submitting, the fence must stay signaled.
        vkResetFences(vk_device, 1, &currentFrame.m_SubmitFence);

        // Flush per-swapchain-image resources to destroy
        if (context->m_MainResourcesToDestroy[frameInFlight]->Size() > 0)
        {
            FlushResourcesToDestroy(context, context->m_MainResourcesToDestroy[frameInFlight]);
        }

        if (context->m_FenceResourcesToDestroy.Capacity() > 0)
        {
            FlushFenceResourcesToDestroy(context);
        }

        // Reset per-frame scratch buffer and descriptor pools
        ScratchBuffer* scratch = &context->m_MainScratchBuffers[frameInFlight];
        context->m_DescriptorAllocatorGeneration[frameInFlight]++;
        ResetScratchBuffer(vk_device, scratch);

        res = scratch->m_DeviceBuffer.MapMemory(vk_device);
        CHECK_VK_ERROR(res);