HorizontalTreeLayoutAlgorithm.java

/*******************************************************************************
 * Copyright 2005, CHISEL Group, University of Victoria, Victoria, BC, Canada.
 * 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:
 *     The Chisel Group, University of Victoria
 *******************************************************************************/
package org.eclipse.zest.layouts.algorithms;

import org.eclipse.zest.layouts.LayoutStyles;
import org.eclipse.zest.layouts.dataStructures.InternalNode;
import org.eclipse.zest.layouts.dataStructures.InternalRelationship;




/**
 * A simple algorithm to arrange graph nodes in a layered horizontal tree-like layout. 
 * @see TreeLayoutAlgorithm
 * 
 * @version  1.0
 * @author   Rob Lintern
 */
public class HorizontalTreeLayoutAlgorithm extends TreeLayoutAlgorithm {

	
	/**
	 * Creates a horizontal tree layout with no style
	 */
	public HorizontalTreeLayoutAlgorithm() {
		this( LayoutStyles.NONE );
	}
	
    /**
     * 
     */
    public HorizontalTreeLayoutAlgorithm( int styles ) {
        super( styles );
    }
    
    protected void preLayoutAlgorithm(InternalNode[] entitiesToLayout, InternalRelationship[] relationshipsToConsider, double x, double y, double width, double height) {
        // NOTE: width and height are swtiched here when calling super method
        super.preLayoutAlgorithm(entitiesToLayout, relationshipsToConsider, x, y, height, width); 
    }
    
    protected void postLayoutAlgorithm(InternalNode[] entitiesToLayout, InternalRelationship[] relationshipsToConsider) {
        // swap x->y and width->height
        for (int i = 0; i < entitiesToLayout.length; i++) {
            InternalNode entity = entitiesToLayout[i];
			entity.setInternalLocation(entity.getInternalY(), entity.getInternalX() );
			entity.setInternalSize( entity.getInternalWidth(), entity.getInternalHeight() );
        }
    	super.postLayoutAlgorithm(entitiesToLayout, relationshipsToConsider);
    }
    
    protected boolean isValidConfiguration(boolean asynchronous, boolean continueous) {
		if ( asynchronous && continueous ) return false;
		else if ( asynchronous && !continueous ) return true;
		else if ( !asynchronous && continueous ) return false;
		else if ( !asynchronous && !continueous ) return true;
		
		return false;
    }

}