Text shifts while drawing using Graphics2D, TextLayout and AffineTransform

Question

Hi,
Text is drawn to Panel using Graphics2D, TextLayout and AffineTransform. A rectangle is drawn around the text where one side of rectangle touches text. When I rotate Text and Rectangle by 90 degrees around the center, text is shifted by one pixel away from the side of the rectangle.
Please see the below code: For rotation change the angle from 0 to 90
import java.awt.Color;
import java.awt.Dimension;
import java.awt.FontMetrics;
import java.awt.Graphics;
import java.awt.Graphics2D;
import java.awt.RenderingHints;
import java.awt.event.WindowAdapter;
import java.awt.event.WindowEvent;
import java.awt.font.TextAttribute;
import java.awt.font.TextLayout;
import java.awt.geom.AffineTransform;
import java.awt.geom.Rectangle2D;
import java.text.AttributedString;
import javax.swing.JFrame;
import javax.swing.JPanel;
public class DrawText extends JPanel {
     public DrawText() {
          setBackground(Color.white);
          setSize(350, 400);
     private static void adjustGraphics(Graphics2D g) {
          g.setRenderingHint(RenderingHints.KEY_ANTIALIASING,
                    RenderingHints.VALUE_ANTIALIAS_ON);
          g.setRenderingHint(RenderingHints.KEY_TEXT_ANTIALIASING,
                    RenderingHints.VALUE_TEXT_ANTIALIAS_ON);
          g.setRenderingHint(RenderingHints.KEY_FRACTIONALMETRICS,
                    RenderingHints.VALUE_FRACTIONALMETRICS_ON);
          g.setRenderingHint(RenderingHints.KEY_RENDERING,
                    RenderingHints.VALUE_RENDER_QUALITY);
     public void paintComponent(Graphics g) {
          super.paintComponent(g);
          Graphics2D g2 = (Graphics2D) g;
          adjustGraphics(g2);
          g2.setColor(Color.black);
          String toPrint = "Draw Text Test!";
          double nX = 100, nY = 100, width = 100, height = 0;
          double angle = 0;// Change the angle from 0 to 90
          angle = Math.toRadians(angle);
          FontMetrics fm = this.getFontMetrics(g2.getFont());
          height = fm.getHeight();
          AffineTransform afNew = new AffineTransform();
          afNew.rotate(-angle, nX + width / 2.0, nY + height / 2.0);
          g2.setTransform(afNew);
          g2.draw(new Rectangle2D.Double(nX, nY, width, height));
          nY = nY + (fm.getAscent() - fm.getLeading());
          AttributedString attStr = new AttributedString(toPrint);
          attStr.addAttribute(TextAttribute.FONT, g2.getFont());
          TextLayout textLayout = new TextLayout(attStr.getIterator(), g2
                    .getFontRenderContext());
          nX = nX - textLayout.getBounds().getX();
          textLayout.draw(g2, (float) nX, (float) nY);
     public static void main(String arg[]) {
          JFrame frame = new JFrame();
          frame.addWindowListener(new WindowAdapter() {
               public void windowClosing(WindowEvent e) {
                    System.exit(0);
          frame.getContentPane().add("Center", new DrawText());
          frame.pack();
          frame.setSize(new Dimension(350, 400));
          frame.setVisible(true);
}

Answer 1

Include a timer that slowly increases the the angle from 0 to 90 and repaints each time. You'll notice that at some angles the "D" is flushed with the rectangle, while at other angles (like 90) it's offset by one pixel. If you look at all the letters at once, though, you'll notice they shake about quite a bit. Sometimes one letter is closer to another letter, while other times they're farther apart. A screenshot of any given angle looks OK, but when in slow motion you see just how inexact text rendering under a transformation may be.