public void SetScrollPosition(int numDown)
{
mFirstVisibleIndex = numDown;
if (mAlignment == ScrollBarAlignment.Vertical)
{
mPositionBar.WorldUnitRelativeY = ScaleY - (float)(2 + mPositionBar.ScaleY + numDown * (2 * (mScaleY - 2) * mSensitivity));
}
else
{
mPositionBar.WorldUnitRelativeX = ScaleX - (float)(2 + mPositionBar.ScaleX + numDown * (2 * (mScaleX - 2) * mSensitivity));
}
}