Bug 210635 Incorrect preview of chart after reverse categories.
chart/org.eclipse.birt.chart.engine/src/org/eclipse/birt/chart/computation/withaxes/PlotWith2DAxes.java
dX = daTickCoordinates.getStart( ) + dUnitSize * i;
						try
						{
							dY = getLocation( scOrthogonal, oDataOrthogonal );
						}
						catch ( IllegalArgumentException nvex )
						{
							
							dY = Double.NaN;
						}
						catch ( ChartException dfex )
						{
							dY = dOrthogonalZero; 
						}
					}
				}
				else
				{
					
					try
					{
						dX = getLocation( scBase, oDataBase );
					}
					catch ( IllegalArgumentException nvex )
					{
						dX = dBaseZero;
					}
					catch ( ChartException dfex )
					{
						dX = dBaseZero;