Initial release

engine/vendor/vst3sdk/base/source/timer.h

@@ -0,0 +1,162 @@
+//------------------------------------------------------------------------
+// Project     : SDK Base
+// Version     : 1.0
+// 
+// Category    : Helpers
+// Filename    : base/source/timer.h
+// Created by  : Steinberg, 05/2006
+// Description : Timer class for receiving tiggers at regular intervals
+// 
+//-----------------------------------------------------------------------------
+// This file is part of a Steinberg SDK. It is subject to the license terms
+// in the LICENSE file found in the top-level directory of this distribution
+// and at www.steinberg.net/sdklicenses. 
+// No part of the SDK, including this file, may be copied, modified, propagated,
+// or distributed except according to the terms contained in the LICENSE file.
+//-----------------------------------------------------------------------------
+
+#pragma once
+
+#include "fobject.h"
+#include <limits>
+
+#if SMTG_CPP17
+#include <functional>
+#endif
+
+namespace Steinberg {
+class Timer;
+
+//------------------------------------------------------------------------
+namespace SystemTime {
+
+uint64 getTicks64 ();
+
+inline uint64 getTicksDuration (uint64 old, uint64 now)
+{
+	if (old > now)
+		return (std::numeric_limits<uint64>::max) () - old + now;
+	return now - old;
+}
+
+int32 getTicks (); ///< deprecated, use getTicks64 ()
+
+//------------------------------------------------------------------------
+} // namespace SystemTime
+
+//------------------------------------------------------------------------
+/** @class ITimerCallback
+
+    Implement this callback interface to receive triggers from a timer.
+    Note: This interface is intended as a mix-in class and therefore does not provide ref-counting.
+
+    @see Timer */
+class ITimerCallback
+{
+public:
+	virtual ~ITimerCallback () {}
+	/** This method is called at the end of each interval.
+	    \param timer The timer which calls. */
+	virtual void onTimer (Timer* timer) = 0;
+};
+
+template <typename Call>
+ITimerCallback* newTimerCallback (const Call& call)
+{
+	struct Callback : public ITimerCallback
+	{
+		Callback (const Call& call) : call (call) {}
+		void onTimer (Timer* timer) SMTG_OVERRIDE { call (timer); }
+		Call call;
+	};
+	return NEW Callback (call);
+}
+
+#if SMTG_CPP17
+//------------------------------------------------------------------------
+/** @class TimerCallback
+ *
+ *  a timer callback object using a funtion for the timer call
+ */
+struct TimerCallback final : ITimerCallback
+{
+    using CallbackFunc = std::function<void (Timer*)>;
+
+    TimerCallback (CallbackFunc&& f) : f (std::move (f)) {}
+    TimerCallback (const CallbackFunc& f) : f (f) {}
+
+	void onTimer (Timer* timer) override { f (timer); }
+
+private:
+	CallbackFunc f;
+};
+
+#endif // SMTG_CPP17
+
+// -----------------------------------------------------------------
+/** @class Timer
+
+    Timer is a class that allows you to receive triggers at regular intervals.
+    Note: The timer class is an abstract base class with (hidden) platform specific subclasses.
+
+    Usage:
+    @code
+    class TimerReceiver : public FObject, public ITimerCallback
+    {
+        ...
+        virtual void onTimer (Timer* timer)
+        {
+            // do stuff
+        }
+        ...
+    };
+
+    TimerReceiver* receiver =  new TimerReceiver ();
+    Timer* myTimer = Timer::create (receiver, 100); // interval: every 100ms
+  
+    ...
+    ...
+
+    if (myTimer)
+        myTimer->release ();
+    if (receiver)
+        receiver->release ();
+    @endcode
+
+    @see ITimerCallback
+ */
+class Timer : public FObject
+{
+public:
+	/** Create a timer with a given interval
+	    \param callback The receiver of the timer calls.
+	    \param intervalMilliseconds The timer interval in milliseconds.
+	    \return The created timer if any, callers owns the timer. The timer starts immediately.
+	*/
+	static Timer* create (ITimerCallback* callback, uint32 intervalMilliseconds);
+
+	virtual void stop () = 0; ///< Stop the timer.
+};
+
+// -----------------------------------------------------------------
+/** @class DisableDispatchingTimers
+
+    Disables dispatching of timers for the live time of this object
+*/
+class DisableDispatchingTimers
+{
+public:
+	DisableDispatchingTimers ();
+	~DisableDispatchingTimers ();
+
+private:
+	bool oldState;
+};
+
+#if SMTG_OS_LINUX
+using CreateTimerFunc = Timer* (*)(ITimerCallback* callback, uint32 intervalMilliseconds);
+void InjectCreateTimerFunction (CreateTimerFunc f);
+#endif
+
+//------------------------------------------------------------------------
+} // namespace Steinberg