Allow stepping through the time delta in multiple passes in snowballs

--HG--
branch : multipass-stereo

code/snowballs2/client/src/game_time.cpp

@@ -42,6 +42,14 @@ static bool _SkipAnimationOnce;
 static NLMISC::TTime _TimeMs;
 static CValueSmootherTemplate<float> _FpsSmoother;
 
+namespace
+{
+
+NLMISC::TLocalTime a_LocalTimeDelta;
+NL3D::TGlobalAnimationTime a_AnimationTimeDelta;
+
+} /* anonymous namespace */
+
 static void cbFpsSmoothing(CConfigFile::CVar &var)
 {
 	_FpsSmoother.init((uint)var.asInt());
@@ -53,8 +61,10 @@ void CGameTime::init()
 	_TimeMs = NLMISC::CTime::getLocalTime();
 	LocalTime = ((TLocalTime)_TimeMs) / 1000.0;
 	LocalTimeDelta = 0.0;
+	a_LocalTimeDelta = 0.0;
 	AnimationTime = 0.0;
 	AnimationTimeDelta = 0.f;
+	a_AnimationTimeDelta = 0.0;
 	FramesPerSecond = 0.f;
 	FramesPerSecondSmooth = 0.f;
 	CConfiguration::setAndCallback("FpsSmoothing", cbFpsSmoothing);
@@ -78,26 +88,24 @@ void CGameTime::updateTime()
 		// average of previous fps and this fps should be ok
 		FramesPerSecond *= 3;
 
-		LocalTimeDelta = 0.f;
+		a_LocalTimeDelta = 0.f;
-		AnimationTimeDelta = 0.f;
+		a_AnimationTimeDelta = 0.f;
 	}
 	else
 	{
 		FramesPerSecond = 1000.0f / (float)deltams;
 
 		TLocalTime localTime = ((TLocalTime)timems) / 1000.0;
-		LocalTimeDelta = localTime - LocalTime;
+		a_LocalTimeDelta = localTime - LocalTime;
-		LocalTime = localTime;
 
 		if (_SkipAnimationOnce)
 		{
-			AnimationTimeDelta = 0.f;
+			a_AnimationTimeDelta = 0.f;
 			_SkipAnimationOnce = false;
 		}
 		else
 		{
-			AnimationTimeDelta = (TAnimationTime)LocalTimeDelta;
+			a_AnimationTimeDelta = (TGlobalAnimationTime)a_LocalTimeDelta;
-			AnimationTime += (TGlobalAnimationTime)LocalTimeDelta;
 		}
 	}
 
@@ -105,6 +113,15 @@ void CGameTime::updateTime()
 	FramesPerSecondSmooth = _FpsSmoother.getSmoothValue();
 }
 
+void CGameTime::advanceTime(double f)
+{
+	LocalTimeDelta = a_LocalTimeDelta * f;
+	LocalTime += LocalTimeDelta;
+	TGlobalAnimationTime atd = a_AnimationTimeDelta * f;
+	AnimationTimeDelta = (NL3D::TAnimationTime)atd;
+	AnimationTime += atd;
+}
+
 void CGameTime::skipAnimationOnce()
 {
 	_SkipAnimationOnce = true;

code/snowballs2/client/src/game_time.h

@@ -40,6 +40,9 @@ public:
 
 	static void updateTime();
 
+	/// Advance time to target time by factor f.
+	static void advanceTime(double f);
+
 	/// Used when loading, this will skip changing animation time on the next update
 	/// (updates aren't called during loading)
 	static void skipAnimationOnce();

code/snowballs2/client/src/snowballs_client.cpp

@@ -679,6 +679,7 @@ void loopIngame()
 
 		// 02. Update Time (deltas)
 		CGameTime::updateTime();
+		CGameTime::advanceTime(1.0);
 
 		// 03. Update Input (keyboard controls, etc)
 		Driver->EventServer.pump(); // Pump user input messages