Improve RTPatchCPU update time (cf. commit 726cd02)

Author: CodeFHD

src/slg/engines/rtpathcpu/rtpathcpu.cpp

@@ -51,6 +51,10 @@ void RTPathCPURenderEngine::StartLockLess() {
 }
 
 void RTPathCPURenderEngine::StopLockLess() {
+	// We need to resume paused sessions first,
+	// otherwise it will hang on a thread barrier.
+	if(pauseMode)
+		Resume();
 	PathCPURenderEngine::StopLockLess();
 }
 

src/slg/engines/rtpathcpu/rtpathcputhread.cpp

@@ -85,17 +85,13 @@ void RTPathCPURenderThread::RTRenderFunc(std::stop_token stop_token) {
 			// Synchronize all threads -> This waits for RTPathCPURenderEngine::PauseThreads()
 			engine->threadsSyncBarrier->arrive_and_wait();
 
-			while (!stop_token.stop_requested() && engine->threadsPauseMode)
-				std::this_thread::sleep_for(100ms);
+			// Wait for the main thread -> This waits for RTPathCPURenderEngine::ResumeThreads()
+			engine->threadsSyncBarrier->arrive_and_wait();
 
-			// If the above loop was broken because of the stop, we don't want to enter the second
-			// arrive_and_wait() because that would wait for the resume signal, which won't come.
+			// If the engine was stopped, we break here.
 			if (stop_token.stop_requested())
 				break;
 
-			// Wait for the main thread -> This waits for RTPathCPURenderEngine::ResumeThreads()
-			engine->threadsSyncBarrier->arrive_and_wait();
-
 			(static_cast<RTPathCPUSampler *>(sampler.get()))->Reset(FilmPtr(&engine->GetFilm()));
 		}