Rotate45Degrees.java Source code

Introduction

Here is the source code for Rotate45Degrees.java

Source

import org.eclipse.swt.SWT;
import org.eclipse.swt.events.PaintEvent;
import org.eclipse.swt.events.PaintListener;
import org.eclipse.swt.graphics.Font;
import org.eclipse.swt.graphics.GC;
import org.eclipse.swt.graphics.Image;
import org.eclipse.swt.graphics.Rectangle;
import org.eclipse.swt.graphics.Transform;
import org.eclipse.swt.layout.FillLayout;
import org.eclipse.swt.widgets.Canvas;
import org.eclipse.swt.widgets.Display;
import org.eclipse.swt.widgets.Shell;

public class Rotate45Degrees {
    public static void main(String[] args) {
        final Display display = new Display();

        final Image image = new Image(display, 110, 60);
        GC gc = new GC(image);
        Font font = new Font(display, "Times", 30, SWT.BOLD);
        gc.setFont(font);
        gc.setBackground(display.getSystemColor(SWT.COLOR_RED));
        gc.fillRectangle(0, 0, 110, 60);
        gc.setForeground(display.getSystemColor(SWT.COLOR_WHITE));
        gc.drawText("SWT", 10, 10, true);
        font.dispose();
        gc.dispose();

        final Rectangle rect = image.getBounds();
        Shell shell = new Shell(display);
        shell.setText("Matrix Tranformations");
        shell.setLayout(new FillLayout());

        final Canvas canvas = new Canvas(shell, SWT.DOUBLE_BUFFERED);
        canvas.addPaintListener(new PaintListener() {
            public void paintControl(PaintEvent e) {
                GC gc = e.gc;
                gc.setAdvanced(true);
                if (!gc.getAdvanced()) {
                    gc.drawText("Advanced graphics not supported", 30, 30, true);
                    return;
                }

                // Original image
                int x = 30, y = 30;
                gc.drawImage(image, x, y);
                x += rect.width + 30;

                Transform transform = new Transform(display);

                // Rotate by 45 degrees 
                //float cos45 = (float)Math.cos(45);
                float cos45 = (float) Math.cos(Math.PI / 4);

                //float sin45 = (float)Math.sin(45);
                float sin45 = (float) Math.sin(Math.PI / 4);

                transform.setElements(cos45, sin45, -sin45, cos45, 0, 0);
                gc.setTransform(transform);
                gc.drawImage(image, 350, 100);

                transform.dispose();
            }
        });

        shell.setSize(350, 550);
        shell.open();
        while (!shell.isDisposed()) {
            if (!display.readAndDispatch())
                display.sleep();
        }
        image.dispose();
        display.dispose();
    }
}