Bug 188283 Bubbles should be z-sorted by size in Bubble charts
Biggest bubbles should be drawn first so that there is no small bubble hidden by a bigger one.
chart/org.eclipse.birt.chart.engine/src/org/eclipse/birt/chart/event/MarkerInstruction.java
/*******************************************************************************
 * Copyright (c) 2007 Actuate Corporation.
 * All rights reserved. This program and the accompanying materials
 * are made available under the terms of the Eclipse Public License v1.0
 * which accompanies this distribution, and is available at
 * http://www.eclipse.org/legal/epl-v10.html
 *
 * Contributors:
 *  Actuate Corporation  - initial API and implementation
 *******************************************************************************/
package org.eclipse.birt.chart.event;
import org.eclipse.birt.chart.exception.ChartException;
import org.eclipse.birt.chart.model.attribute.Bounds;
import org.eclipse.birt.chart.render.DeferredCache;
/**
 * This class wraps a rendering event for Marker
 */
public class MarkerInstruction implements Comparable