1 files changed, 100 insertions, 0 deletions
diff --git a/Box2D/Common/b2Timer.cpp b/Box2D/Common/b2Timer.cpp
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+++ b/Box2D/Common/b2Timer.cpp
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+/*
+* Copyright (c) 2011 Erin Catto http://box2d.org
+*
+* This software is provided 'as-is', without any express or implied
+* warranty.  In no event will the authors be held liable for any damages
+* arising from the use of this software.
+* Permission is granted to anyone to use this software for any purpose,
+* including commercial applications, and to alter it and redistribute it
+* freely, subject to the following restrictions:
+* 1. The origin of this software must not be misrepresented; you must not
+* claim that you wrote the original software. If you use this software
+* in a product, an acknowledgment in the product documentation would be
+* appreciated but is not required.
+* 2. Altered source versions must be plainly marked as such, and must not be
+* misrepresented as being the original software.
+* 3. This notice may not be removed or altered from any source distribution.
+*/
+
+#include <Box2D/Common/b2Timer.h>
+
+#if defined(_WIN32)
+
+float64 b2Timer::s_invFrequency = 0.0f;
+
+#include <windows.h>
+
+b2Timer::b2Timer()
+{
+	LARGE_INTEGER largeInteger;
+
+	if (s_invFrequency == 0.0f)
+	{
+		QueryPerformanceFrequency(&largeInteger);
+		s_invFrequency = float64(largeInteger.QuadPart);
+		if (s_invFrequency > 0.0f)
+		{
+			s_invFrequency = 1000.0f / s_invFrequency;
+		}
+	}
+
+	QueryPerformanceCounter(&largeInteger);
+	m_start = float64(largeInteger.QuadPart);
+}
+
+void b2Timer::Reset()
+{
+	LARGE_INTEGER largeInteger;
+	QueryPerformanceCounter(&largeInteger);
+	m_start = float64(largeInteger.QuadPart);
+}
+
+float32 b2Timer::GetMilliseconds() const
+{
+	LARGE_INTEGER largeInteger;
+	QueryPerformanceCounter(&largeInteger);
+	float64 count = float64(largeInteger.QuadPart);
+	float32 ms = float32(s_invFrequency * (count - m_start));
+	return ms;
+}
+
+#elif defined(__linux__) || defined (__APPLE__)
+
+#include <sys/time.h>
+
+b2Timer::b2Timer()
+{
+    Reset();
+}
+
+void b2Timer::Reset()
+{
+    timeval t;
+    gettimeofday(&t, 0);
+    m_start_sec = t.tv_sec;
+    m_start_msec = t.tv_usec * 0.001f;
+}
+
+float32 b2Timer::GetMilliseconds() const
+{
+    timeval t;
+    gettimeofday(&t, 0);
+    return (t.tv_sec - m_start_sec) * 1000 + t.tv_usec * 0.001f - m_start_msec;
+}
+
+#else
+
+b2Timer::b2Timer()
+{
+}
+
+void b2Timer::Reset()
+{
+}
+
+float32 b2Timer::GetMilliseconds() const
+{
+	return 0.0f;
+}
+
+#endif