Merge pull request #1639 from vsg-dev/FrameSemaphores

Frame semaphores

Author: robertosfield

include/vsg/app/Window.h

@@ -122,9 +122,11 @@ namespace vsg
             ref_ptr<ImageView> imageView;
             ref_ptr<Framebuffer> framebuffer;
             ref_ptr<Semaphore> imageAvailableSemaphore;
+            ref_ptr<Semaphore> renderFinishedSemaphore;
         };
 
         using Frames = std::vector<Frame>;
+        using Semaphores = std::vector<ref_ptr<Semaphore>>;
 
         Frame& frame(size_t i) { return _frames[i]; }
         Frames& frames() { return _frames; }
@@ -173,10 +175,11 @@ namespace vsg
         ref_ptr<Image> _multisampleDepthImage;
         ref_ptr<ImageView> _multisampleDepthImageView;
 
-        ref_ptr<Semaphore> _availableSemaphore;
-
         Frames _frames;
         std::vector<size_t> _indices;
+
+        Semaphores _availableSemaphores;
+        size_t _availableSemaphoreIndex = 0;
     };
     VSG_type_name(vsg::Window);
 

src/vsg/app/Presentation.cpp

@@ -34,6 +34,9 @@ VkResult Presentation::present()
         {
             vk_swapchains.emplace_back(*(window->getOrCreateSwapchain()));
             indices.emplace_back(static_cast<uint32_t>(imageIndex));
+
+            auto& renderFinishedSemaphore = window->frame(imageIndex).renderFinishedSemaphore;
+            vk_semaphores.push_back(renderFinishedSemaphore->vk());
         }
     }
 

src/vsg/app/RecordAndSubmitTask.cpp

@@ -215,27 +215,33 @@ VkResult RecordAndSubmitTask::finish(ref_ptr<RecordedCommandBuffers> recordedCom
     if (earlyDataTransferredSemaphore) transferTask->assignTransferConsumedCompletedSemaphore(TransferTask::TRANSFER_BEFORE_RECORD_TRAVERSAL, earlyTransferConsumerCompletedSemaphore);
     if (lateDataTransferredSemaphore) transferTask->assignTransferConsumedCompletedSemaphore(TransferTask::TRANSFER_AFTER_RECORD_TRAVERSAL, lateTransferConsumerCompletedSemaphore);
 
+    current_fence->dependentSemaphores().clear();
+
     for (auto& window : windows)
     {
         auto imageIndex = window->imageIndex();
         if (imageIndex >= window->numFrames()) continue;
 
-        auto& semaphore = window->frame(imageIndex).imageAvailableSemaphore;
+        auto& frame = window->frame(imageIndex);
 
-        vk_waitSemaphores.emplace_back(*semaphore);
-        vk_waitStages.emplace_back(semaphore->pipelineStageFlags());
+        vk_waitSemaphores.emplace_back(frame.imageAvailableSemaphore->vk());
+        vk_waitStages.emplace_back(frame.imageAvailableSemaphore->pipelineStageFlags());
+
+        vk_signalSemaphores.emplace_back(frame.renderFinishedSemaphore->vk());
+        current_fence->dependentSemaphores().push_back(frame.renderFinishedSemaphore);
     }
 
     for (auto& semaphore : waitSemaphores)
     {
-        vk_waitSemaphores.emplace_back(*(semaphore));
+        vk_waitSemaphores.emplace_back(semaphore->vk());
         vk_waitStages.emplace_back(semaphore->pipelineStageFlags());
     }
 
     current_fence->dependentSemaphores() = signalSemaphores;
     for (auto& semaphore : signalSemaphores)
     {
-        vk_signalSemaphores.emplace_back(*(semaphore));
+        vk_signalSemaphores.emplace_back(semaphore->vk());
+        current_fence->dependentSemaphores().push_back(semaphore);
     }
 
     if (earlyDataTransferredSemaphore)

src/vsg/app/Viewer.cpp

@@ -524,13 +524,10 @@ void Viewer::assignRecordAndSubmitTaskAndPresentation(CommandGraphs in_commandGr
 
             Windows activeWindows(findWindows.windows.begin(), findWindows.windows.end());
 
-            auto renderFinishedSemaphore = vsg::Semaphore::create(device);
-
             // set up Submission with CommandBuffer and signals
             auto recordAndSubmitTask = vsg::RecordAndSubmitTask::create(device, numBuffers);
             recordAndSubmitTask->commandGraphs = commandGraphs;
             recordAndSubmitTask->databasePager = databasePager;
-            recordAndSubmitTask->signalSemaphores.emplace_back(renderFinishedSemaphore);
             recordAndSubmitTask->windows = activeWindows;
             recordAndSubmitTask->queue = mainQueue;
             recordAndSubmitTasks.emplace_back(recordAndSubmitTask);
@@ -541,7 +538,6 @@ void Viewer::assignRecordAndSubmitTaskAndPresentation(CommandGraphs in_commandGr
             if (instrumentation) recordAndSubmitTask->assignInstrumentation(instrumentation);
 
             auto presentation = vsg::Presentation::create();
-            presentation->waitSemaphores.emplace_back(renderFinishedSemaphore);
             presentation->windows = activeWindows;
             presentation->queue = device->getQueue(deviceQueueFamily.presentFamily);
             presentations.emplace_back(presentation);

src/vsg/app/Window.cpp

@@ -370,8 +370,6 @@ void Window::buildSwapchain()
     // set up framebuffer and associated resources
     auto& imageViews = _swapchain->getImageViews();
 
-    _availableSemaphore = vsg::Semaphore::create(_device, _traits->imageAvailableSemaphoreWaitFlag);
-
     size_t initial_indexValue = imageViews.size();
     for (size_t i = 0; i < imageViews.size(); ++i)
     {
@@ -391,12 +389,18 @@ void Window::buildSwapchain()
         ref_ptr<Framebuffer> fb = Framebuffer::create(_renderPass, attachments, _extent2D.width, _extent2D.height, 1);
 
         ref_ptr<Semaphore> ias = vsg::Semaphore::create(_device, _traits->imageAvailableSemaphoreWaitFlag);
+        ref_ptr<Semaphore> rfs = vsg::Semaphore::create(_device);
 
-        //_frames.push_back({multisampling ? _multisampleImageView : imageViews[i], fb, ias});
-        _frames.push_back({imageViews[i], fb, ias});
+        _frames.push_back({imageViews[i], fb, ias, rfs});
         _indices.push_back(initial_indexValue);
     }
 
+    _availableSemaphoreIndex = 0;
+    for (size_t i = 0; i < imageViews.size(); ++i)
+    {
+        _availableSemaphores.push_back(vsg::Semaphore::create(_device, _traits->imageAvailableSemaphoreWaitFlag));
+    }
+
     {
         // ensure image attachments are setup on GPU.
         auto commandPool = CommandPool::create(_device, graphicsFamily);
@@ -434,18 +438,19 @@ VkResult Window::acquireNextImage(uint64_t timeout)
 {
     if (!_swapchain) _initSwapchain();
 
-    if (!_availableSemaphore) _availableSemaphore = vsg::Semaphore::create(_device, _traits->imageAvailableSemaphoreWaitFlag);
+    auto& availableSemaphore = _availableSemaphores[_availableSemaphoreIndex];
+    _availableSemaphoreIndex = (_availableSemaphoreIndex + 1) % _availableSemaphores.size();
 
     // check the dimensions of the swapchain and window extents are consistent, if not return a VK_ERROR_OUT_OF_DATE_KHR
     if (_swapchain->getExtent() != _extent2D) return VK_ERROR_OUT_OF_DATE_KHR;
 
     uint32_t nextImageIndex;
-    VkResult result = _swapchain->acquireNextImage(timeout, _availableSemaphore, {}, nextImageIndex);
+    VkResult result = _swapchain->acquireNextImage(timeout, availableSemaphore, {}, nextImageIndex);
 
     if (result == VK_SUCCESS)
     {
         // the acquired image's semaphore must be available now so make it the new _availableSemaphore and set its entry to the one to use for the next frame by swapping ref_ptr<>'s
-        _availableSemaphore.swap(_frames[nextImageIndex].imageAvailableSemaphore);
+        availableSemaphore.swap(_frames[nextImageIndex].imageAvailableSemaphore);
 
         // shift up previous frame indices
         for (size_t i = _indices.size() - 1; i > 0; --i)