Function drawFrame

cpp/5_Domain_Specific/simpleVulkan/main.cpp:455–516

    }

    void drawFrame()
    {
        static chrono_tp startTime = std::chrono::high_resolution_clock::now();

        chrono_tp currentTime = std::chrono::high_resolution_clock::now();
        float     time = std::chrono::duration<float, std::chrono::seconds::period>(currentTime - startTime).count();

        if (m_currentFrame == 0) {
            m_lastTime = startTime;
        }

        float frame_time = std::chrono::duration<float, std::chrono::seconds::period>(currentTime - m_lastTime).count();

        // Have vulkan draw the current frame...
        VulkanBaseApp::drawFrame();

#ifdef _VK_TIMELINE_SEMAPHORE
        static uint64_t waitValue   = 1;
        static uint64_t signalValue = 2;

        cudaExternalSemaphoreWaitParams waitParams = {};
        waitParams.flags                           = 0;
        waitParams.params.fence.value              = waitValue;

        cudaExternalSemaphoreSignalParams signalParams = {};
        signalParams.flags                             = 0;
        signalParams.params.fence.value                = signalValue;
        // Wait for vulkan to complete it's work
        checkCudaErrors(cudaWaitExternalSemaphoresAsync(&m_cudaTimelineSemaphore, &waitParams, 1, m_stream));
        // Now step the simulation
        m_sim.stepSimulation(time, m_stream);
        // Signal vulkan to continue with the updated buffers
        checkCudaErrors(cudaSignalExternalSemaphoresAsync(&m_cudaTimelineSemaphore, &signalParams, 1, m_stream));

        waitValue += 2;
        signalValue += 2;
#else
        cudaExternalSemaphoreWaitParams waitParams = {};
        waitParams.flags                           = 0;
        waitParams.params.fence.value              = 0;

        cudaExternalSemaphoreSignalParams signalParams = {};
        signalParams.flags                             = 0;
        signalParams.params.fence.value                = 0;

        // Wait for vulkan to complete it's work
        checkCudaErrors(cudaWaitExternalSemaphoresAsync(&m_cudaWaitSemaphore, &waitParams, 1, m_stream));
        // Now step the simulation
        m_sim.stepSimulation(time, m_stream);
        // Signal vulkan to continue with the updated buffers
        checkCudaErrors(cudaSignalExternalSemaphoresAsync(&m_cudaSignalSemaphore, &signalParams, 1, m_stream));
#endif /* _VK_TIMELINE_SEMAPHORE */

        // Output a naive measurement of the frames per second every five seconds
        if (frame_time > 5) {
            std::cout << "Average FPS (over " << std::fixed << std::setprecision(2) << frame_time
                      << " seconds): " << std::fixed << std::setprecision(2)
                      << ((m_currentFrame - m_lastFrame) / frame_time) << std::endl;