Bug 211773 Legend entries overlap
chart/org.eclipse.birt.chart.engine/src/org/eclipse/birt/chart/render/BaseRenderer.java
* @return Returns device renderer associated with current renderer.
	 */
	public final IDeviceRenderer getDevice( )
	{
		return ir;
	}
	/**
	 * Renders a 2D or extruded 2D plane as necessary for a given front surface
	 * polygon. Takes into account the correct z-ordering of each plane and
	 * applies basic lighting. This convenience method may be used by series
	 * type rendering extensions if needed.
	 * 
	 * @param ipr
	 *            A handle to the primitive rendering device
	 * @param oSource
	 *            The object wrapped in the polygon rendering event
	 * @param loaFront
	 *            The co-ordinates of the front face polygon
	 * @param f
	 *            The fill color for the front face
	 * @param lia
	 *            The edge color for the polygon
	 * @param dSeriesThickness
	 *            The thickness or the extrusion level (for 2.5D or 3D)
	 * 
	 * @throws RenderingException
	 */
	protected final void renderPlane( IPrimitiveRenderer ipr, Object oSource,
			Location[] loaFront, Fill f, LineAttributes lia, ChartDimension cd,
			double dSeriesThickness, boolean bDeferred ) throws ChartException