ImageIconHelper.java

/*
* Copyright 2013 Simon Thiel
*
* This file is part of SitJar.
*
* SitJar is free software: you can redistribute it and/or modify
* it under the terms of the GNU LESSER GENERAL PUBLIC LICENSE as published by
* the Free Software Foundation, either version 3 of the License, or
* (at your option) any later version.
* 
* SitJar 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 Lesser General Public License for more details.
* 
* You should have received a copy of the GNU Lesser General Public License
* along with SitJar. If not, see <http://www.gnu.org/licenses/lgpl.txt>.
*/

/**
 * ImageIconHelper.java
 *
 * 23-Apr-2010
 *
 * @author Simon Thiel <simon.thiel@gmx.de>
 *
 */
package sit.graphics;

import java.awt.Graphics;
import java.awt.Graphics2D;
import java.awt.GraphicsConfiguration;
import java.awt.GraphicsDevice;
import java.awt.GraphicsEnvironment;
import java.awt.HeadlessException;
import java.awt.Image;
import java.awt.Transparency;
import java.awt.image.BufferedImage;
import java.awt.image.PixelGrabber;
import javax.swing.ImageIcon;

/**
 * class ImageIconHelper
 *
 */
public class ImageIconHelper {

    public boolean hasAlpha(Image image) {
        // If buffered image, the color model is readily available
        if (image instanceof BufferedImage) {
            return ((BufferedImage) image).getColorModel().hasAlpha();
        }

        // Use a pixel grabber to retrieve the image's color model;
        // grabbing a single pixel is usually sufficient
        PixelGrabber pg = new PixelGrabber(image, 0, 0, 1, 1, false);
        try {
            pg.grabPixels();
        } catch (InterruptedException e) {
        }

        // Get the image's color model
        return pg.getColorModel().hasAlpha();
    }

    public BufferedImage toBufferedImage(Image image) {

        if (image instanceof BufferedImage) {
            return (BufferedImage) image;
        }

        // This code ensures that all the pixels in the image are loaded
        image = new ImageIcon(image).getImage();

        // Determine if the image has transparent pixels
        boolean hasAlpha = hasAlpha(image);

        // Create a buffered image with a format that's compatible with the
        // screen
        BufferedImage bimage = null;
        GraphicsEnvironment ge =
                GraphicsEnvironment.getLocalGraphicsEnvironment();
        try {
            // Determine the type of transparency of the new buffered image
            int transparency = Transparency.OPAQUE;
            if (hasAlpha == true) {
                transparency = Transparency.BITMASK;
            }

            // Create the buffered image
            GraphicsDevice gs = ge.getDefaultScreenDevice();
            GraphicsConfiguration gc = gs.getDefaultConfiguration();
            bimage = gc.createCompatibleImage(image.getWidth(null), image.
                    getHeight(null), transparency);
        } catch (HeadlessException e) {
        } // No screen


        if ((bimage == null) || (bimage.getType() == 0)) {
            // Create a buffered image using the default color model
            int type = BufferedImage.TYPE_INT_RGB;
            if (hasAlpha == true) {
                type = BufferedImage.TYPE_INT_ARGB;
            }
            bimage = new BufferedImage(image.getWidth(null), image.getHeight(
                    null), type);

        }

        // Copy image to buffered image
        Graphics g = bimage.createGraphics();

        // Paint the image onto the buffered image
        g.drawImage(image, 0, 0, null);
        g.dispose();

        return bimage;
    }



    public BufferedImage tilt(BufferedImage image, double angle) {
        double sin = Math.abs(Math.sin(angle)), cos = Math.abs(Math.cos(angle));
        int w = image.getWidth(), h = image.getHeight();
        int neww = (int) Math.floor(w * cos + h * sin), newh = (int) Math.floor(
                h * cos + w * sin);

        GraphicsConfiguration gc = getDefaultConfiguration();
        BufferedImage result =
                gc.createCompatibleImage(neww, newh, Transparency.TRANSLUCENT);
        Graphics2D g = result.createGraphics();

        //System.out.println("rotate:"+angle+" w:"+w+" h:"+h+" neww:"+neww+" newh:"+newh);
        
        g.translate((neww - w) / 2, (newh - h) / 2);
        g.rotate(angle, w / 2, h / 2);
        g.drawRenderedImage(image, null);
        g.dispose();
        return result;
    }

    public GraphicsConfiguration getDefaultConfiguration() {
        GraphicsEnvironment ge =
                GraphicsEnvironment.getLocalGraphicsEnvironment();
        GraphicsDevice gd = ge.getDefaultScreenDevice();
        return gd.getDefaultConfiguration();
    }

    public Image rotateImage(Image img, double degree) {
    
        if (degree==0){
            return img;
        }

        BufferedImage bufImg = toBufferedImage(img);
        double angle = Math.toRadians(degree);

        return tilt(bufImg, angle);
    }
}