Bug 194785 Stacked bars are drawn incompletely when window is minimed
If I have a stacked bar chart, and i minimize window or bring another window in front so that the view is blocked by the new window, when the window is minimized, all the drawing in the charts is erased, and the view has to be closed and re-opened before the charts appear correctly again. I think this problem is because of the fix for 182279. I will attach the sample test case
chart/org.eclipse.birt.chart.engine/src/org/eclipse/birt/chart/computation/withaxes/AxisSubUnit.java
if ( dPositiveTotal - dNegativeTotal == 0 )
		{
			return 0;
		}
		
		return ( dValue * 100d ) / ( dPositiveTotal - dNegativeTotal );
	}
	/**
	 * Saves the last position and uses to compute current position by adding
	 * margin
	 * 
	 * @param dValue
	 *            value to check the max or min location
	 * @param dBaseLocation
	 *            base location when last position is null
	 * @param dMargin
	 *            margin location
	 * @see "https://bugs.eclipse.org/bugs/show_bug.cgi?id=182279"
	 */
	public final void setLastPosition( double dValue, double dBaseLocation,
			double dMargin )
	{
		if ( bStackTogether || dValue >= 0 )
		{
			if ( !Double.isNaN( dLastMaxPosition ) )
			{
				dBaseLocation = dLastMaxPosition;
			}
			dBaseLocation += dMargin;
			dLastMaxPosition = dBaseLocation;