Bug 176582 "Show Lines as Curves" does not work correctly for Area Chart [0001]
Description: "Show Lines as Curves" does not work correctly for Area Chart. Build number: 2.2.0.v20070307-1128 Steps to reproduce: 1. New a Area Chart. 2. In "Format Chart" tab, select Series->Value (Y) Series, tick and untick "Show Lines as Curves" checkbox. Expected result: Null value point e is treated the same when tick and untick "Show Lines as Curves" checkbox. Actual result: Null value point e is treated differently (see the screenshot). Error log: N/A
chart/org.eclipse.birt.chart.engine/src/org/eclipse/birt/chart/render/BaseRenderer.java
/**
	 * Returns if the right-left mode is enabled.
	 * 
	 * @return
	 */
	public boolean isRightToLeft( )
	{
		if ( rtc == null )
		{
			return false;
		}
		return rtc.isRightToLeft( );
	}
	/**
	 * Returns if current palette is from the category series.
	 * 
	 * @return
	 */
	protected boolean isPaletteByCategory( )
	{
		return ( cm.getLegend( ).getItemType( ).getValue( ) == LegendItemType.CATEGORIES );
	}
	/**
	 * Switch Anchor value due to right-left setting.
	 * 
	 * @param anchor
	 * @return
	 */
	public Anchor switchAnchor( Anchor anchor )
	{