Bug 212291 SWT Chart render engine always uses 96 DPI(Display) resolution
chart/org.eclipse.birt.chart.engine/src/org/eclipse/birt/chart/computation/withaxes/PlotWith2DAxes.java
* This method pulls out the 'min' and 'max' value for all datasets
	 * associated with a single axis using the custom data source processor
	 * implementation
	 * 
	 * @param ax
	 *            The orthogonal axis for which the min/max values are being
	 *            computed
	 * @param iType
	 *            The renderer's axis data type
	 * 
	 * @return
	 */
	private final Object getMinMax( Axis ax, int iType ) throws ChartException,
			IllegalArgumentException
	{
		final Series[] sea = ax.getRuntimeSeries( );
		final int iSeriesCount = sea.length;
		Series se;
		DataSet ds;
		Object oV1, oV2, oMin = null, oMax = null;
		PluginSettings ps = PluginSettings.instance( );
		IDataSetProcessor iDSP = null;
		
		boolean bAnyStacked = false;
		for ( int i = 0; i < iSeriesCount; i++ )
		{
			if ( sea[i].isStacked( ) )
			{
				if ( sea[i].canBeStacked( ) )
				{