add timeout to avoid unnecessarily high cpu usage.

Plugins/uDesktopDuplication/uDesktopDuplication/Common.cpp

@@ -62,3 +62,18 @@ void SendMessageToUnity(Message message)
 {
     g_messages.push(message);
 }
+
+
+ScopedTimer::ScopedTimer(TimerFuncType&& func)
+    : func_(func)
+    , start_(std::chrono::high_resolution_clock::now())
+{
+}
+
+
+ScopedTimer::~ScopedTimer()
+{
+    const auto end = std::chrono::high_resolution_clock::now();
+    const auto time = std::chrono::duration_cast<microseconds>(end - start_);
+    func_(time);
+}

Plugins/uDesktopDuplication/uDesktopDuplication/Common.h

@@ -2,6 +2,7 @@
 
 #include <functional>
 #include <memory>
+#include <chrono>
 #include <wrl/client.h>
 
 
@@ -32,7 +33,23 @@ public:
     ~ScopedReleaser() { func_(); }
 
 private:
-    ReleaseFuncType func_;
+    const ReleaseFuncType func_;
+};
+
+
+
+// Timer
+class ScopedTimer
+{
+public:
+    using microseconds = std::chrono::microseconds;
+    using TimerFuncType = std::function<void(microseconds)>;
+    ScopedTimer(TimerFuncType&& func);
+    ~ScopedTimer();
+
+private:
+    const TimerFuncType func_;
+    const std::chrono::time_point<std::chrono::steady_clock> start_;
 };
 
 

Plugins/uDesktopDuplication/uDesktopDuplication/Duplicator.cpp

@@ -1,5 +1,7 @@
 #pragma once
 
+#include <chrono>
+
 #include "Duplicator.h"
 #include "Monitor.h"
 #include "MonitorManager.h"
@@ -139,12 +141,25 @@ void Duplicator::Start()
 
     thread_ = std::thread([this] 
     {
+        using namespace std::chrono;
+
         state_ = State::Running;
 
         shouldRun_ = true;
         while (shouldRun_)
         {
-            if (!Duplicate()) break;
+            const UINT timeout = 16 /* milliseconds */;
+
+            ScopedTimer timer([timeout] (microseconds us)
+            {
+                const auto waitTime = milliseconds(timeout) - us;
+                if (waitTime > microseconds::zero())
+                {
+                    std::this_thread::sleep_for(waitTime);
+                }
+            });
+
+            if (!Duplicate(timeout)) break;
         }
 
         if (state_ == State::Running)
@@ -211,12 +226,10 @@ const Duplicator::Frame& Duplicator::GetLastFrame() const
 }
 
 
-bool Duplicator::Duplicate()
+bool Duplicator::Duplicate(UINT timeout)
 {
     if (!dupl_ || !device_) return false;
 
-    const UINT timeout = 16;
-
     ComPtr<IDXGIResource> resource;
     DXGI_OUTDUPL_FRAME_INFO frameInfo;
     const auto hr = dupl_->AcquireNextFrame(timeout, &frameInfo, &resource);

Plugins/uDesktopDuplication/uDesktopDuplication/Duplicator.h

@@ -67,7 +67,7 @@ private:
     void InitializeDuplication();
     void CheckUnityAdapter();
 
-    bool Duplicate();
+    bool Duplicate(UINT timeout);
 
     void UpdateCursor(
         const Microsoft::WRL::ComPtr<ID3D11Texture2D>& texture,