The video decoding thread efficiently waits for a video to be created before doing anything, rather than sleeping for 2ms in a loop. Reduces the CPU usage of the video worker thread to ~0% when no videos are loaded.

src/modules/video/theora/Video.cpp

@@ -71,6 +71,7 @@ void Worker::addStream(VideoStream *stream)
 {
 	love::thread::Lock l(mutex);
 	streams.push_back(stream);
+	cond->broadcast();
 }
 
 void Worker::stop()
@@ -78,6 +79,7 @@ void Worker::stop()
 	{
 		love::thread::Lock l(mutex);
 		stopping = true;
+		cond->broadcast();
 	}
 
 	owner->wait();
@@ -85,34 +87,39 @@ void Worker::stop()
 
 void Worker::threadFunction()
 {
-	double lastFrame = love::timer::Timer::getTimeSinceEpoch();
+	double lastFrame = love::timer::Timer::getTime();
+
 	while (true)
 	{
-		double curFrame = love::timer::Timer::getTimeSinceEpoch();
+		love::sleep(2);
+
+		love::thread::Lock l(mutex);
+
+		while (!stopping && streams.empty())
+		{
+			cond->wait(mutex);
+			lastFrame = love::timer::Timer::getTime();
+		}
+
+		if (stopping)
+			return;
+
+		double curFrame = love::timer::Timer::getTime();
 		double dt = curFrame-lastFrame;
 		lastFrame = curFrame;
 
+		for (auto it = streams.begin(); it != streams.end(); ++it)
 		{
-			love::thread::Lock l(mutex);
-
-			if (stopping)
-				return;
-
-			for (auto it = streams.begin(); it != streams.end(); ++it)
+			VideoStream *stream = *it;
+			if (stream->getReferenceCount() == 1)
 			{
-				VideoStream *stream = *it;
-				if (stream->getReferenceCount() == 1)
-				{
-					// We're the only ones left
-					streams.erase(it);
-					break;
-				}
-
-				stream->threadedFillBackBuffer(dt);
+				// We're the only ones left
+				streams.erase(it);
+				break;
 			}
-		}
 
-		love::sleep(2);
+			stream->threadedFillBackBuffer(dt);
+		}
 	}
 }
 

src/modules/video/theora/Video.h

@@ -68,10 +68,13 @@ public:
 	void stop();
 
 private:
-	std::vector<StrongRef<VideoStream>> streams;
-	love::thread::MutexRef mutex;
 
-	volatile bool stopping;
+	std::vector<StrongRef<VideoStream>> streams;
+
+	love::thread::MutexRef mutex;
+	love::thread::ConditionalRef cond;
+
+	bool stopping;
 }; // Worker
 
 } // theora