Framerate manager is now in a separate file and private member of GH

client/gui/FramerateManager.cpp

@@ -0,0 +1,65 @@
+/*
+ * FramerateManager.h, part of VCMI engine
+ *
+ * Authors: listed in file AUTHORS in main folder
+ *
+ * License: GNU General Public License v2.0 or later
+ * Full text of license available in license.txt file, in main folder
+ *
+ */
+
+#include "StdInc.h"
+#include "FramerateManager.h"
+
+#include <SDL_timer.h>
+
+FramerateManager::FramerateManager(int newRate)
+	: rate(0)
+	, rateticks(0)
+	, fps(0)
+	, accumulatedFrames(0)
+	, accumulatedTime(0)
+	, lastticks(0)
+	, timeElapsed(0)
+{
+	init(newRate);
+}
+
+void FramerateManager::init(int newRate)
+{
+	rate = newRate;
+	rateticks = 1000.0 / rate;
+	this->lastticks = SDL_GetTicks();
+}
+
+void FramerateManager::framerateDelay()
+{
+	ui32 currentTicks = SDL_GetTicks();
+
+	timeElapsed = currentTicks - lastticks;
+	accumulatedFrames++;
+
+	// FPS is higher than it should be, then wait some time
+	if(timeElapsed < rateticks)
+	{
+		int timeToSleep = (uint32_t)ceil(this->rateticks) - timeElapsed;
+		boost::this_thread::sleep(boost::posix_time::milliseconds(timeToSleep));
+	}
+
+	currentTicks = SDL_GetTicks();
+	// recalculate timeElapsed for external calls via getElapsed()
+	// limit it to 100 ms to avoid breaking animation in case of huge lag (e.g. triggered breakpoint)
+	timeElapsed = std::min<ui32>(currentTicks - lastticks, 100);
+
+	lastticks = SDL_GetTicks();
+
+	accumulatedTime += timeElapsed;
+
+	if(accumulatedFrames >= 100)
+	{
+		//about 2 second should be passed
+		fps = static_cast<int>(ceil(1000.0 / (accumulatedTime / accumulatedFrames)));
+		accumulatedTime = 0;
+		accumulatedFrames = 0;
+	}
+}