protected override IBrush GetCurrentValue(Double runningPct) { var a = Convert.ToByte(_startA + _alphaDiff * runningPct); var r = Convert.ToByte(_startR + _rDiff * runningPct); var g = Convert.ToByte(_startG + _gDiff * runningPct); var b = Convert.ToByte(_startB + _bDiff * runningPct); return(SolidColorBrush.FromArgb(a, r, g, b)); }