src/content/platform/guide/tutorials/paintTutorial/PaintCanvas.java

/*
 * DO NOT ALTER OR REMOVE COPYRIGHT NOTICES OR THIS HEADER.
 *
 * Copyright 1997-2007 Sun Microsystems, Inc. All rights reserved.
 *
 * The contents of this file are subject to the terms of either the GNU
 * General Public License Version 2 only ("GPL") or the Common
 * Development and Distribution License("CDDL") (collectively, the
 * "License"). You may not use this file except in compliance with the
 * License. You can obtain a copy of the License at
 * https://netbeans.org/cddl-gplv2.html
 * or nbbuild/licenses/CDDL-GPL-2-CP. See the License for the
 * specific language governing permissions and limitations under the
 * License.  When distributing the software, include this License Header
 * Notice in each file and include the License file at
 * nbbuild/licenses/CDDL-GPL-2-CP.  Sun designates this
 * particular file as subject to the "Classpath" exception as provided
 * by Sun in the GPL Version 2 section of the License file that
 * accompanied this code. If applicable, add the following below the
 * License Header, with the fields enclosed by brackets [] replaced by
 * your own identifying information:
 * "Portions Copyrighted [year] [name of copyright owner]"
 *
 * Contributor(s):
 *
 * The Original Software is NetBeans. The Initial Developer of the Original
 * Software is Sun Microsystems, Inc. Portions Copyright 1997-2006 Sun
 * Microsystems, Inc. All Rights Reserved.
 *
 * If you wish your version of this file to be governed by only the CDDL
 * or only the GPL Version 2, indicate your decision by adding
 * "[Contributor] elects to include this software in this distribution
 * under the [CDDL or GPL Version 2] license." If you do not indicate a
 * single choice of license, a recipient has the option to distribute
 * your version of this file under either the CDDL, the GPL Version 2 or
 * to extend the choice of license to its licensees as provided above.
 * However, if you add GPL Version 2 code and therefore, elected the GPL
 * Version 2 license, then the option applies only if the new code is
 * made subject to such option by the copyright holder.
 */

package org.netbeans.paint;

import java.awt.Color;
import java.awt.Dimension;
import java.awt.Graphics;
import java.awt.Graphics2D;
import java.awt.Paint;
import java.awt.Point;
import java.awt.RenderingHints;
import java.awt.event.MouseEvent;
import java.awt.event.MouseListener;
import java.awt.event.MouseMotionListener;
import java.awt.geom.AffineTransform;
import java.awt.image.BufferedImage;
import javax.swing.JComponent;

/**
 *
 * @author Timothy Boudreau
 */
public class PaintCanvas extends JComponent implements MouseListener, MouseMotionListener {
    
    public PaintCanvas() {
	addMouseListener (this);
	addMouseMotionListener (this);
	setBackground (Color.WHITE);
    }
    
    private int diam = 10;
    public void setBrush (int diam) {
	this.diam = diam;
    }
    
    public void setDiam (int val) {
	this.diam = val;
    }
    
    public int getDiam() {
	return diam;
    }
    
    private Paint paint = Color.BLUE;
    public void setPaint (Paint c) {
	this.paint = c;
    }
    
    public Paint getPaint() {
	return paint;
    }
    
    public Color getColor() {
	if (paint instanceof Color) {
	    return (Color) paint;
	} else {
	    return Color.BLACK;
	}
    }
    
    private BufferedImage backingImage = null;
    public void clear () {
	backingImage = null;
	repaint();
    }
    
    public BufferedImage getImage() {
	if (backingImage == null || backingImage.getWidth() != getWidth() || backingImage.getHeight() != getHeight()) {
	    BufferedImage old = backingImage;
	    backingImage = new BufferedImage (getWidth(), getHeight(), BufferedImage.TYPE_INT_ARGB_PRE);
	    Graphics g = backingImage.getGraphics();
	    g.setColor (Color.WHITE);
	    g.fillRect (0, 0, getWidth(), getHeight());
	    if (old != null) {
		((Graphics2D) backingImage.getGraphics()).drawRenderedImage(old, 
			AffineTransform.getTranslateInstance(0, 0));
	    }
	}
	return backingImage;
    }
    
    public void paint (Graphics g) {
	Graphics2D g2d = (Graphics2D) g;
	g2d.drawRenderedImage(getImage(), AffineTransform.getTranslateInstance(0,0));
    }

    public void mouseClicked(MouseEvent e) {
	Point p = e.getPoint();
	int half = diam / 2;
	Graphics g = getImage().getGraphics();
	((Graphics2D) g).setRenderingHint(RenderingHints.KEY_ANTIALIASING, RenderingHints.VALUE_ANTIALIAS_ON);
	((Graphics2D) g).setPaint (getPaint());
	g.fillOval(p.x - half, p.y - half, diam, diam);
	repaint (p.x - half, p.y - half, diam, diam);
    }

    public void mousePressed(MouseEvent e) {
    }

    public void mouseReleased(MouseEvent e) {
    }

    public void mouseEntered(MouseEvent e) {
    }

    public void mouseExited(MouseEvent e) {
    }

    public void mouseDragged(MouseEvent e) {
	mouseClicked (e);
    }

    public void mouseMoved(MouseEvent e) {
    }
    
    JComponent createBrushSizeView() {
        return new BrushSizeView();
    }
    
    
    private class BrushSizeView extends JComponent {
	
	public boolean isOpaque() {
	    return true;
	}
	
	public void paint (Graphics g) {
	    ((Graphics2D) g).setRenderingHint(RenderingHints.KEY_ANTIALIASING, RenderingHints.VALUE_ANTIALIAS_ON);
	    g.setColor (getBackground());
	    g.fillRect (0,0,getWidth(),getHeight());
	    Point p = new Point (getWidth() / 2, getHeight() / 2);
	    int half = getDiam() / 2;
	    int diam = getDiam();
	    g.setColor (getColor());
	    g.fillOval(p.x - half, p.y - half, diam, diam);
	}
	
	public Dimension getPreferredSize() {
	    return new Dimension (32, 32);
	}
	
	public Dimension getMinimumSize() {
	    return getPreferredSize();
	}
    }    
}