AlgoImageCorner.java

/* 
GeoGebra - Dynamic Mathematics for Everyone
http://www.geogebra.org

This file is part of GeoGebra.

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.

 */

package org.geogebra.common.kernel.algos;

import org.geogebra.common.kernel.Construction;
import org.geogebra.common.kernel.commands.Commands;
import org.geogebra.common.kernel.geos.GeoElement;
import org.geogebra.common.kernel.geos.GeoImage;
import org.geogebra.common.kernel.geos.GeoNumberValue;
import org.geogebra.common.kernel.geos.GeoPoint;

public class AlgoImageCorner extends AlgoElement {

	private GeoImage img; // input
	private GeoPoint corner; // output
	private GeoNumberValue number;

	public AlgoImageCorner(Construction cons, String label, GeoImage img,
			GeoNumberValue number) {
		super(cons);
		this.img = img;
		this.number = number;

		corner = new GeoPoint(cons);
		setInputOutput(); // for AlgoElement
		compute();
		corner.setLabel(label);

		cons.registerEuclidianViewCE(this);

	}

	@Override
	public Commands getClassName() {
		return Commands.Corner;
	}

	// for AlgoElement
	@Override
	protected void setInputOutput() {
		input = new GeoElement[2];
		input[0] = img;
		input[1] = number.toGeoElement();

		super.setOutputLength(1);
		super.setOutput(0, corner);
		setDependencies(); // done by AlgoElement
	}

	public GeoPoint getCorner() {
		return corner;
	}

	@Override
	public final void compute() {
		img.calculateCornerPoint(corner, (int) number.getDouble());
	}

	@Override
	public boolean euclidianViewUpdate() {

		// update image to update it's bounding box
		kernel.notifyUpdate(img);

		// now compute()
		compute();

		// update corner
		corner.update();

		return true; // update cascade of dependent objects done in Construction
	}

}