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
int iSeriesIndex, iDataSetCount = ssl.getUnitCount( );
			for ( int k = 0; k < iDataSetCount; k++ ) 
			{
				iSeriesIndex = 0;
				for ( int i = 0; i < alSeriesGroupsPerAxis.size( ); i++ )
				{
					sg = (StackGroup) alSeriesGroupsPerAxis.get( i );
					alSeriesPerGroup = sg.getSeries( );
					iSeriesPerGroup = alSeriesPerGroup.size( );
					if ( iSeriesPerGroup > 0 )
					{
						se = (Series) alSeriesPerGroup.get( 0 );
						ds = se.getDataSet( );
						if ( dsi[iSeriesIndex] == null )
						{
							dsi[iSeriesIndex] = new DataSetIterator( ds );
							
							dsi[iSeriesIndex].reverse( cwa.isReverseCategory( ) );
							
							if ( ( dsi[iSeriesIndex].getDataType( ) & IConstants.NUMERICAL ) != IConstants.NUMERICAL )
							{
								throw new ChartException( ChartEnginePlugin.ID,
										ChartException.DATA_SET,
										"exception.percent.stacked.non.numerical",  
										Messages.getResourceBundle( rtc.getULocale( ) ) );
							}
						}
						
						iDataSetCount = dsi[iSeriesIndex].size( );
						final AxisSubUnit au = ssl.getSubUnit( sg, k );