view java/src/uk/ac/qmul/eecs/ccmi/gui/GraphElement.java @ 3:9e67171477bc

PHANTOM Omni Heptic device release

/*  
 CCmI Editor - A Collaborative Cross-Modal Diagram Editing Tool
  
 Copyright (C) 2011  Queen Mary University of London (http://ccmi.eecs.qmul.ac.uk/)

 This program is free software: you can redistribute it and/or modify
 it under the terms of the GNU General Public License as published by
 the Free Software Foundation, either version 3 of the License, or
 (at your option) any later version.

 This program is distributed in the hope that it will be useful,
 but WITHOUT ANY WARRANTY; without even the implied warranty of
 MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
 GNU General Public License for more details.

 You should have received a copy of the GNU General Public License
 along with this program.  If not, see <http://www.gnu.org/licenses/>.
*/
package uk.ac.qmul.eecs.ccmi.gui;

import java.awt.Graphics2D;
import java.awt.geom.Point2D;
import java.awt.geom.Rectangle2D;


/**
 * An interface implemented by {@code Node}, {@code Edge} and {@code Edge.InnerPoint}. It defines methods that 
 * all objects painted on a graph share. The interface is used mainly
 * for convenience in treating the different types of object in a uniformly.  
 *
 */
public interface GraphElement {
	/**
	 * Draw the graphic element on a canvas
	 * 
	 * @param g2 the graphics object. Use {@code g2.draw()} to get things painted on the graph. 
	 */
	public void draw(Graphics2D g2);

	/**
	 * Translates this graphic element on the graph 
	 * 
	 * @param p the starting point where the translation starts (normally where the user clicks
	 * with their mouse)
	 * @param dx the distance to translate along the x-axis
	 * @param dy the distance to translate along the y-axis
	 * @param source the source of the translate action
	 */
	public void translate(Point2D p, double dx, double dy, Object source);

	/**
	 * This method is to be called before translation or any other operation that changes the 
	 * position of the graph element or any of its parts. 
	 * 
	 * @param p the starting point of the motion 
	 * @param source the source of the motion action
	 */
	public void startMove(Point2D p, Object source);

	/**
	 * This method is to be called when the motion (e.g. a translation) is over. 
	 * Note that for instance a translation might be composed on several calls to {@code translate}
	 * 
	 * @param source
	 */
	public void stopMove(Object source);
	
	/**
	 * Gets the bounding {@code Rectangle} of this graph element.
	 * 
	 * @return a new {@code Rectangle} equals to the bounding {@code Rectangle} of this graph element
	 */
	public Rectangle2D getBounds();
	
	/**
	 * Returns the point where an line, with a specified direction, would come in contact with the outline of this 
	 * graph element. 
	 * 
	 * @param d the direction of the line 
	 * @return a new point on the outline if this graph element where the line comes in contact with it
 	 */
	public Point2D getConnectionPoint(Direction d);
	
	/**
	 * Tests if a specified {@code Point2D} is inside the boundary of this graph element.
	 * 
	 * @param p the point to be tested
	 * @return {@code true} if the point is inside the boundary, {@code false} otherwise
	 */
	public boolean contains(Point2D p);
	
}