Avoid reusing semaphores that may still be in flight

include/vsg/app/Presentation.h

@@ -24,7 +24,6 @@ namespace vsg
         VkResult present();
 
         Windows windows;
-        Semaphores waitSemaphores; // taken from RecordAndSubmitTasks.signalSemaphores
 
         ref_ptr<Queue> queue; // assign in application for GraphicsQueue from device
     };

include/vsg/app/RecordAndSubmitTask.h

@@ -39,7 +39,6 @@ namespace vsg
         Windows windows;
         Semaphores waitSemaphores;   // assign in application setup
         CommandGraphs commandGraphs; // assign in application setup
-        Semaphores signalSemaphores; // connect to Presentation.waitSemaphores
 
         ref_ptr<TransferTask> transferTask; // data is transferred for this frame
 

include/vsg/app/Window.h

@@ -122,6 +122,7 @@ namespace vsg
             ref_ptr<ImageView> imageView;
             ref_ptr<Framebuffer> framebuffer;
             ref_ptr<Semaphore> imageAvailableSemaphore;
+            ref_ptr<Semaphore> renderFinishedSemaphore;
         };
 
         using Frames = std::vector<Frame>;

src/vsg/app/Presentation.cpp

@@ -20,10 +20,6 @@ VkResult Presentation::present()
     //debug("Presentation::present()");
 
     std::vector<VkSemaphore> vk_semaphores;
-    for (auto& semaphore : waitSemaphores)
-    {
-        vk_semaphores.emplace_back(*(semaphore));
-    }
 
     std::vector<VkSwapchainKHR> vk_swapchains;
     std::vector<uint32_t> indices;
@@ -34,6 +30,9 @@ 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);
         }
     }
 

src/vsg/app/RecordAndSubmitTask.cpp

@@ -215,6 +215,8 @@ 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();
@@ -224,6 +226,10 @@ VkResult RecordAndSubmitTask::finish(ref_ptr<RecordedCommandBuffers> recordedCom
 
         vk_waitSemaphores.emplace_back(*semaphore);
         vk_waitStages.emplace_back(semaphore->pipelineStageFlags());
+
+        auto& renderFinishedSemaphore = window->frame(imageIndex).renderFinishedSemaphore;
+        vk_signalSemaphores.emplace_back(*renderFinishedSemaphore);
+        current_fence->dependentSemaphores().push_back(renderFinishedSemaphore);
     }
 
     for (auto& semaphore : waitSemaphores)
@@ -232,12 +238,6 @@ VkResult RecordAndSubmitTask::finish(ref_ptr<RecordedCommandBuffers> recordedCom
         vk_waitStages.emplace_back(semaphore->pipelineStageFlags());
     }
 
-    current_fence->dependentSemaphores() = signalSemaphores;
-    for (auto& semaphore : signalSemaphores)
-    {
-        vk_signalSemaphores.emplace_back(*(semaphore));
-    }
-
     if (earlyDataTransferredSemaphore)
     {
         vk_signalSemaphores.emplace_back(earlyTransferConsumerCompletedSemaphore->vk());

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

@@ -447,6 +447,9 @@ VkResult Window::acquireNextImage(uint64_t timeout)
         // 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);
 
+        if (!_frames[nextImageIndex].renderFinishedSemaphore)
+            _frames[nextImageIndex].renderFinishedSemaphore = vsg::Semaphore::create(_device);
+
         // shift up previous frame indices
         for (size_t i = _indices.size() - 1; i > 0; --i)
         {