Added ElapsedTime.

1 files changed, 41 insertions, 0 deletions

diff --git a/win32/PlatWin.cxx b/win32/PlatWin.cxx
index 666c962cf..d227aa7a1 100644
--- a/win32/PlatWin.cxx
+++ b/win32/PlatWin.cxx
@@ -10,6 +10,7 @@
 #include <ctype.h>
 #include <stdarg.h>
 #include <stdio.h>
+#include <time.h>
 
 #define _WIN32_WINNT  0x0400
 #include <windows.h>
@@ -872,6 +873,46 @@ void Menu::Show(Point pt, Window &w) {
 	Destroy();
 }
 
+static bool initialisedET = false;
+static bool usePerformanceCounter = false;
+static LARGE_INTEGER frequency;
+
+static double Now() {
+	if (usePerformanceCounter) {
+		LARGE_INTEGER timeVal;
+		::QueryPerformanceCounter(&timeVal);
+		return *(reinterpret_cast<double *>(&timeVal));
+	} else {
+		return clock();
+	}
+}
+
+ElapsedTime::ElapsedTime() {
+	if (!initialisedET) {
+		usePerformanceCounter = ::QueryPerformanceFrequency(&frequency);
+		initialisedET = true;
+	}
+	beginTime = Now();
+}
+
+double ElapsedTime::Duration(bool reset) {
+	double endTime = Now();
+	double result;
+	if (usePerformanceCounter) {
+		LARGE_INTEGER lBegin = *(reinterpret_cast<LARGE_INTEGER *>(&beginTime));
+		LARGE_INTEGER lEnd = *(reinterpret_cast<LARGE_INTEGER *>(&endTime));
+		double elapsed = lEnd.QuadPart - lBegin.QuadPart;
+		result = elapsed / static_cast<double>(frequency.QuadPart);
+	} else {
+		double elapsed = endTime - beginTime;
+		result = elapsed / CLOCKS_PER_SEC;
+	}
+	if (reset) {
+		beginTime = endTime;
+	}
+	return result;
+}
+
 ColourDesired Platform::Chrome() {
 	return ::GetSysColor(COLOR_3DFACE);
 }