boofcv.gui.image.ImageZoomPanel Maven / Gradle / Ivy

Go to download
Show more of this group Show more artifacts with this name
Show all versions of visualize Show documentation
BoofCV is an open source Java library for real-time computer vision and robotics applications.
The newest version!
/*
 * Copyright (c) 2011-2015, Peter Abeles. All Rights Reserved.
 *
 * This file is part of BoofCV (http://boofcv.org).
 *
 * Licensed under the Apache License, Version 2.0 (the "License");
 * you may not use this file except in compliance with the License.
 * You may obtain a copy of the License at
 *
 *   http://www.apache.org/licenses/LICENSE-2.0
 *
 * Unless required by applicable law or agreed to in writing, software
 * distributed under the License is distributed on an "AS IS" BASIS,
 * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
 * See the License for the specific language governing permissions and
 * limitations under the License.
 */

package boofcv.gui.image;

import georegression.struct.point.Point2D_F64;

import javax.swing.*;
import java.awt.*;
import java.awt.geom.AffineTransform;
import java.awt.image.BufferedImage;


/**
 * Simple JPanel for displaying buffered images allows images to be zoomed in and out of
 *
 * @author Peter Abeles
 */
public class ImageZoomPanel extends JScrollPane {
	// the image being displayed
	protected BufferedImage img;
	protected ImagePanel panel = new ImagePanel();

	protected double scale=1;

	public ImageZoomPanel(final BufferedImage img ) {
		this.img = img;
		setScale(1);
	}

	public ImageZoomPanel() {
		getViewport().setView(panel);
	}

	public synchronized void setScale( double scale ) {

		Rectangle r = panel.getVisibleRect();
		double centerX = (r.x + r.width/2.0)/this.scale;
		double centerY = (r.y + r.height/2.0)/this.scale;

		this.scale = scale;
		int w=0,h=0;
		if( img != null ) {
			w = (int)Math.ceil(img.getWidth()*scale);
			h = (int)Math.ceil(img.getHeight()*scale);
		}
		panel.setPreferredSize(new Dimension(w, h));
		getViewport().setView(panel);

		centerView(centerX, centerY);
	}

	public synchronized void centerView( double cx , double cy ) {
		Rectangle r = panel.getVisibleRect();
		int x = (int)(cx*scale-r.width/2);
		int y = (int)(cy*scale-r.height/2);

		getHorizontalScrollBar().setValue(x);
		getVerticalScrollBar().setValue(y);
	}


	/**
	 * Change the image being displayed.
	 *
	 * @param image The new image which will be displayed.
	 */
	public synchronized void setBufferedImage(BufferedImage image) {
		this.img = image;

		Dimension prev = getPreferredSize();

		int w=0,h=0;
		if( img != null ) {
			w = (int)Math.ceil(img.getWidth()*scale);
			h = (int)Math.ceil(img.getHeight()*scale);
		}

		if( prev.getWidth() != w || prev.getHeight() != h ) {
			panel.setPreferredSize(new Dimension(w,h));
			getViewport().setView(panel);
		}
	}

	public BufferedImage getImage() {
		return img;
	}

	public Point2D_F64 pixelToPoint(int x, int y) {
		Point2D_F64 ret = new Point2D_F64();
		ret.x = x/scale;
		ret.y = y/scale;

		return ret;
	}

	/**
	 * Paint inside the image panel. Useful for overlays
	 */
	protected void paintInPanel(AffineTransform tran,Graphics2D g2 ) {
		// intentionally empty
	}

	protected class ImagePanel extends JPanel
	{
		@Override
		public void paintComponent(Graphics g) {
			super.paintComponent(g);

			if( img == null ) return;

			Graphics2D g2 = (Graphics2D)g;

			synchronized ( ImageZoomPanel.this ) {
				AffineTransform tran = AffineTransform.getScaleInstance(scale, scale);
				g2.drawImage(img, tran, null);

				paintInPanel(tran, g2);
			}
		}
	}

	public double getScale() {
		return scale;
	}
}