Re: Why does AffineTransform not work on JTextPane?

Oliver Wong wrote:


Thanks for all your help. After days and days of pulling my hair out,
the rotation finally works perfectly. Here's how I ended up doing it:

class TextPanel extends JTextPane {

    // implements rotation for a JTextPane

    private int rotation;
    private int tx, ty;
    private int wide, high;
    private BufferedImage renderedText = null;

    // valid rotation values are:
    // 0 = no rotation
    // 1 = rotation 90 degree clockwise
    // 2 = rotation 180 degrees
    // 3 = rotation 90 degrees counterclockwise

    TextPanel() {
        super();
        rotation = 0;
        tx = 0;
        ty = 0;
    }
    public void setDefaultBounds( int x, int y, int width, int height)
{
        high = height;
        wide = width;
        super.setBounds(x,y,width,height);
    }
    public void setRotation( int newRotation ) {

        newRotation = newRotation % 4;
        if ( rotation != newRotation ) {
            switch (newRotation) {
                case 0 : tx = 0; ty = 0; break;
                case 1 : tx = 1; ty = 0; break;
                case 2 : tx = 1; ty = 1; break;
                case 3 : tx = 0; ty = 1; break;
            }
            if ( newRotation != 0 ) {
                if ( renderedText==null) {
                    rotation = 0; // so that text is actually rendered
                    renderedText = new BufferedImage(wide, high,
BufferedImage.TYPE_INT_RGB);
                    Graphics2D g2D = renderedText.createGraphics();
                    paint( g2D );
                }
            }
            rotation = newRotation; // so the repaint will paint the
rendered image
            if ((rotation%2)==0) {
                setSize(wide,high);
            } else {
                setSize(high,wide);
            }

            repaint();
        }
    }
    public int getRotation() { return rotation; }

    public void paintComponent(Graphics g) {

        if ( rotation == 0 ) {
            super.paintComponent(g);
            return;
        }
        Graphics2D g2 = (Graphics2D) g;
        double angle = rotation * Math.PI/2;
        AffineTransform tr = g2.getTransform();
        if (rotation==2) {
            tr.setToTranslation(wide*tx,high*ty);
        } else {
            tr.setToTranslation(high*tx,wide*ty);
        }
        tr.rotate(angle);
        g2.drawImage(renderedText, tr, this);
    }
}

--gary