port from perforce

evoke-64k/trunk/ev10/TargetValue.h

@@ -0,0 +1,32 @@
+#pragma once
+
+struct STargetValue
+{
+	float m_fValue;
+	float m_fTarget;
+	float m_fSpeed;
+	float m_fAcceleration;
+	float m_fFriction;
+
+	STargetValue
+		( 	float fValue,
+			float fTarget,
+			float fSpeed,
+			float fAcceleration,
+			float fFriction )
+	{
+		m_fValue= fValue;
+		m_fTarget= fTarget;
+		m_fSpeed= fSpeed;
+		m_fAcceleration= fAcceleration;
+		m_fFriction= fFriction;
+	}
+	
+	void timeStep()
+	{
+		m_fValue+= m_fSpeed;
+		float fDist= m_fTarget - m_fValue;
+		m_fSpeed+= fDist * m_fAcceleration;
+		m_fSpeed*= m_fFriction;
+	}
+};