Snippet139.java Source code

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Here is the source code for Snippet139.java

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/*
 * This snippet was adapted from org.eclipse.draw2d.ImageUtilities in 
 * http://dev.eclipse.org/viewcvs/index.cgi/org.eclipse.draw2d/?cvsroot=Tools_Project
 * by Pratik Shah.
 *
 * example snippet: rotate and flip an image
 *
 * For a list of all SWT example snippets see
 * http://dev.eclipse.org/viewcvs/index.cgi/%7Echeckout%7E/platform-swt-home/dev.html#snippets
 */
import org.eclipse.swt.SWT;
import org.eclipse.swt.events.PaintEvent;
import org.eclipse.swt.events.PaintListener;
import org.eclipse.swt.graphics.GC;
import org.eclipse.swt.graphics.Image;
import org.eclipse.swt.graphics.ImageData;
import org.eclipse.swt.widgets.Display;
import org.eclipse.swt.widgets.Shell;

public class Snippet139 {

    static ImageData rotate(ImageData srcData, int direction) {
        int bytesPerPixel = srcData.bytesPerLine / srcData.width;
        int destBytesPerLine = (direction == SWT.DOWN) ? srcData.width * bytesPerPixel
                : srcData.height * bytesPerPixel;
        byte[] newData = new byte[srcData.data.length];
        int width = 0, height = 0;
        for (int srcY = 0; srcY < srcData.height; srcY++) {
            for (int srcX = 0; srcX < srcData.width; srcX++) {
                int destX = 0, destY = 0, destIndex = 0, srcIndex = 0;
                switch (direction) {
                case SWT.LEFT: // left 90 degrees
                    destX = srcY;
                    destY = srcData.width - srcX - 1;
                    width = srcData.height;
                    height = srcData.width;
                    break;
                case SWT.RIGHT: // right 90 degrees
                    destX = srcData.height - srcY - 1;
                    destY = srcX;
                    width = srcData.height;
                    height = srcData.width;
                    break;
                case SWT.DOWN: // 180 degrees
                    destX = srcData.width - srcX - 1;
                    destY = srcData.height - srcY - 1;
                    width = srcData.width;
                    height = srcData.height;
                    break;
                }
                destIndex = (destY * destBytesPerLine) + (destX * bytesPerPixel);
                srcIndex = (srcY * srcData.bytesPerLine) + (srcX * bytesPerPixel);
                System.arraycopy(srcData.data, srcIndex, newData, destIndex, bytesPerPixel);
            }
        }
        // destBytesPerLine is used as scanlinePad to ensure that no padding is
        // required
        return new ImageData(width, height, srcData.depth, srcData.palette, destBytesPerLine, newData);
    }

    static ImageData flip(ImageData srcData, boolean vertical) {
        int bytesPerPixel = srcData.bytesPerLine / srcData.width;
        int destBytesPerLine = srcData.width * bytesPerPixel;
        byte[] newData = new byte[srcData.data.length];
        for (int srcY = 0; srcY < srcData.height; srcY++) {
            for (int srcX = 0; srcX < srcData.width; srcX++) {
                int destX = 0, destY = 0, destIndex = 0, srcIndex = 0;
                if (vertical) {
                    destX = srcX;
                    destY = srcData.height - srcY - 1;
                } else {
                    destX = srcData.width - srcX - 1;
                    destY = srcY;
                }
                destIndex = (destY * destBytesPerLine) + (destX * bytesPerPixel);
                srcIndex = (srcY * srcData.bytesPerLine) + (srcX * bytesPerPixel);
                System.arraycopy(srcData.data, srcIndex, newData, destIndex, bytesPerPixel);
            }
        }
        // destBytesPerLine is used as scanlinePad to ensure that no padding is
        // required
        return new ImageData(srcData.width, srcData.height, srcData.depth, srcData.palette, destBytesPerLine,
                newData);
    }

    public static void main(String[] args) {
        Display display = new Display();

        // create an image with the word "hello" on it
        final Image image0 = new Image(display, 50, 30);
        GC gc = new GC(image0);
        gc.setBackground(display.getSystemColor(SWT.COLOR_RED));
        gc.fillRectangle(image0.getBounds());
        gc.drawString("hello", 5, 5, true);
        gc.dispose();

        ImageData data = image0.getImageData();
        // rotate and flip this image
        final Image image1 = new Image(display, rotate(data, SWT.LEFT));
        final Image image2 = new Image(display, rotate(data, SWT.RIGHT));
        final Image image3 = new Image(display, rotate(data, SWT.DOWN));
        final Image image4 = new Image(display, flip(data, true));
        final Image image5 = new Image(display, flip(data, false));

        Shell shell = new Shell(display);
        // draw the results on the shell
        shell.addPaintListener(new PaintListener() {
            public void paintControl(PaintEvent e) {
                e.gc.drawText("Original Image:", 10, 10, true);
                e.gc.drawImage(image0, 10, 40);
                e.gc.drawText("Left, Right, 180:", 10, 80, true);
                e.gc.drawImage(image1, 10, 110);
                e.gc.drawImage(image2, 50, 110);
                e.gc.drawImage(image3, 90, 110);
                e.gc.drawText("Flipped Vertical, Horizontal:", 10, 170, true);
                e.gc.drawImage(image4, 10, 200);
                e.gc.drawImage(image5, 70, 200);
            }
        });
        shell.setSize(300, 300);
        shell.open();
        while (!shell.isDisposed()) {
            if (!display.readAndDispatch())
                display.sleep();
        }
        image0.dispose();
        image1.dispose();
        image2.dispose();
        image3.dispose();
        image4.dispose();
        image5.dispose();
        display.dispose();
    }
}