S.ex. models: implement support for sample-exact controls in fx-mixer

Works for all faders and send knobs

include/ValueBuffer.h

@@ -122,6 +122,29 @@ public:
 		}
 	}
 
+	void multiply( float f )
+	{
+		for( int i = 0; i < m_length; i++ )
+		{
+			m_values[i] *= f;
+		}
+	}
+	
+	ValueBuffer & operator*=( const float & f )
+	{
+		multiply( f );
+		return *this;
+	}
+	
+	ValueBuffer & operator+=( const ValueBuffer & v )
+	{
+		for( int i = 0; i < qMin( m_length, v.length() ); i++ )
+		{
+			m_values[i] += v.values()[i];
+		}
+		return *this;
+	}
+
 	static ValueBuffer interpolatedBuffer( float start, float end, int length )
 	{
 		ValueBuffer vb = ValueBuffer( length );