Implement Counter Queue and Partial Host Conditional Rendering (#1167)

* Implementation of query queue and host conditional rendering

* Resolve some comments.

* Use overloads instead of passing object.

* Wake the consumer threads when incrementing syncpoints.

Also, do a busy loop when awaiting the counter for a blocking flush, rather than potentially sleeping the thread.

* Ensure there's a command between begin and end query.

Ryujinx.Graphics.OpenGL/Queries/CounterQueue.cs

@@ -0,0 +1,209 @@
+using OpenTK.Graphics.OpenGL;
+using Ryujinx.Graphics.GAL;
+using System;
+using System.Collections.Generic;
+using System.Threading;
+
+namespace Ryujinx.Graphics.OpenGL.Queries
+{
+    class CounterQueue : IDisposable
+    {
+        private const int QueryPoolInitialSize = 100;
+
+        public CounterType Type { get; }
+        public bool Disposed { get; private set; }
+
+        private Queue<CounterQueueEvent> _events = new Queue<CounterQueueEvent>();
+        private CounterQueueEvent _current;
+
+        private ulong _accumulatedCounter;
+
+        private object _lock = new object();
+
+        private Queue<BufferedQuery> _queryPool;
+        private AutoResetEvent _queuedEvent = new AutoResetEvent(false);
+        private AutoResetEvent _wakeSignal = new AutoResetEvent(false);
+
+        private Thread _consumerThread;
+
+        internal CounterQueue(CounterType type)
+        {
+            Type = type;
+
+            QueryTarget glType = GetTarget(Type);
+
+            _queryPool = new Queue<BufferedQuery>(QueryPoolInitialSize);
+            for (int i = 0; i < QueryPoolInitialSize; i++)
+            {
+                _queryPool.Enqueue(new BufferedQuery(glType));
+            }
+
+            _current = new CounterQueueEvent(this, glType);
+
+            _consumerThread = new Thread(EventConsumer);
+            _consumerThread.Start();
+        }
+
+        private void EventConsumer()
+        {
+            while (!Disposed)
+            {
+                CounterQueueEvent evt = null;
+                lock (_lock)
+                {
+                    if (_events.Count > 0)
+                    {
+                        evt = _events.Dequeue();
+                    }
+                }
+
+                if (evt == null)
+                {
+                    _queuedEvent.WaitOne(); // No more events to go through, wait for more.
+                }
+                else
+                {
+                    evt.TryConsume(ref _accumulatedCounter, true, _wakeSignal);
+                }
+            }
+        }
+
+        internal BufferedQuery GetQueryObject()
+        {
+            // Creating/disposing query objects on a context we're sharing with will cause issues.
+            // So instead, make a lot of query objects on the main thread and reuse them.
+
+            lock (_lock)
+            {
+                if (_queryPool.Count > 0)
+                {
+                    BufferedQuery result = _queryPool.Dequeue();
+                    return result;
+                }
+                else
+                {
+                    return new BufferedQuery(GetTarget(Type));
+                }
+            }
+        }
+
+        internal void ReturnQueryObject(BufferedQuery query)
+        {
+            lock (_lock)
+            {
+                _queryPool.Enqueue(query);
+            }
+        }
+
+        public CounterQueueEvent QueueReport(EventHandler<ulong> resultHandler)
+        {
+            CounterQueueEvent result;
+
+            lock (_lock)
+            {
+                _current.Complete();
+                _events.Enqueue(_current);
+
+                result = _current;
+                result.OnResult += resultHandler;
+
+                _current = new CounterQueueEvent(this, GetTarget(Type));
+            }
+
+            _queuedEvent.Set();
+
+            return result;
+        }
+
+        public void QueueReset()
+        {
+            lock (_lock)
+            {
+                _current.Clear();
+            }
+        }
+
+        private static QueryTarget GetTarget(CounterType type)
+        {
+            switch (type)
+            {
+                case CounterType.SamplesPassed: return QueryTarget.SamplesPassed;
+                case CounterType.PrimitivesGenerated: return QueryTarget.PrimitivesGenerated;
+                case CounterType.TransformFeedbackPrimitivesWritten: return QueryTarget.TransformFeedbackPrimitivesWritten;
+            }
+
+            return QueryTarget.SamplesPassed;
+        }
+
+        public void Flush(bool blocking)
+        {
+            if (!blocking)
+            {
+                // Just wake the consumer thread - it will update the queries.
+                _wakeSignal.Set();
+                return;
+            }
+
+            lock (_lock)
+            {
+                // Tell the queue to process all events.
+                while (_events.Count > 0)
+                {
+                    CounterQueueEvent flush = _events.Peek();
+                    if (!flush.TryConsume(ref _accumulatedCounter, true))
+                    {
+                        return; // If not blocking, then return when we encounter an event that is not ready yet.
+                    }
+                    _events.Dequeue();
+                }
+            }
+        }
+
+        public void FlushTo(CounterQueueEvent evt)
+        {
+            lock (_lock)
+            {
+                if (evt.Disposed)
+                {
+                    return;
+                }
+
+                // Tell the queue to process all events up to this one.
+                while (_events.Count > 0)
+                {
+                    CounterQueueEvent flush = _events.Dequeue();
+                    flush.TryConsume(ref _accumulatedCounter, true);
+
+                    if (flush == evt)
+                    {
+                        return;
+                    }
+                }
+            }
+        }
+
+        public void Dispose()
+        {
+            lock (_lock)
+            {
+                while (_events.Count > 0)
+                {
+                    CounterQueueEvent evt = _events.Dequeue();
+
+                    evt.Dispose();
+                }
+
+                Disposed = true;
+            }
+
+            _queuedEvent.Set();
+
+            _consumerThread.Join();
+
+            foreach (BufferedQuery query in _queryPool)
+            {
+                query.Dispose();
+            }
+        }
+    }
+}