Advanced drawing of components

Question

Hey all,
I have yet to see a really good book that explains in detail the various capabilities of the Graphics 2D. There are tons of capabilities, like Shape and all its subclasses, Transform, the many methods of Graphics2D, and so on. There are some VERY kick-ass possibilities yet it seems very few people understand how to use these more advanced features of Graphics2D.
As an example, I am trying to create a nice rounded, shadowed panel component with a gradient shadow and definable rounded corners with a definable arc. For the most part, it hasn't been difficult doing the rounded stuff, but trying to get the shadow just right, faded on the rounded curve, and so on has not been easy. I have tried many things, from using fillRoundRect, to fillArc, to looking at using clipping and compositing, possibly a Shape object, etc. I am no graphics expert, so the lack of docs/tutorials that explain how to really use the Graphics2D and all of its capabilities is disappointing. I almost feel I need to be a 2D/3D expert to understand the various features.
So, does anyone have any good links, or book suggestions that really explain Graphics2D and really delve into advanced drawing features, such as creating custom drawn components? Are there some free resources on the net to help out? If not, I will be happy to buy a good book or two.
I want to learn how to use Shape, Compositing, clipping, gradients, transforms, text and fonts, strokes, and so forth in good detail, enough that I can answer a good deal of questions posted in this forum and others and know how to attack a problem like a rounded shaded cornered panel component.
Speaking of, one concern I have with making a rounded panel is how to enforce that components added to the panel are within the inside rounded edges. Is this the job of insets()? I thought of using an internal panel and delegating all the add(), find(), get(), remove() and other methods of the JPanel that I extend (or JComponent), to the internal panel. I have also tried drawing the shadowed portion as a border, so that perhaps (hopefully) I dont need an internal panel component, as that seems a bit messy. But I surely don't want any components to be added that overlap the rounded edges. Any ideas on this?
Thanks

Answer 1

I have been thinking about using it as a border
instead of drawing it as a complete component. I think
that would allow the internal components to be added
to the panel without much fanfare of the rounded
border, although it may still pose a problem should
the rounded edges and shadow take up more space than
they should. I don't know much about insets, but I am
hoping by adjust the insets that the add() methods
would use those to place components within the inset
range and not the entier 0,0,width,height of the panel
itself.That's the job of the layout manager -- if it is stretching components to fill a panel, it should
know about the (left, top, bottom, right) gaps of the insets as dictated by the border and place
components not within rectangle (0, 0, width, height) but within rectangle
(left, top, width-left-right, height-top-bottom).
That being said, I wish I had a nickel for every time I read someone's custom component method,
where their paintComponent assumes that can draw at (0,0) -- no realizing they have to offset for the
insets of the border!
A demo that shows GridLayout knows about borders:
import java.awt.*;
import javax.swing.*;
import javax.swing.border.*;
public class ExampleBorder implements Border {
    private int thickness;
    private Color color;
    ExampleBorder(int thickness, Color color) {
        this.thickness = thickness;
        this.color = color;
    public Insets getBorderInsets(Component c) {
        return new Insets(thickness, thickness, 0, 0);
    public boolean isBorderOpaque() {
        return false;
    public void paintBorder(Component c, Graphics g, int x, int y, int width, int height) {
        Color oldColor = g.getColor();
        g.setColor(color);
        if (width > thickness)
            g.fillRect(x, y, width-thickness, thickness);
        if (height > thickness)
            g.fillRect(x, y, thickness, height-thickness);
        g.setColor(oldColor);
    //convenience
    public JComponent wrap(JComponent comp) {
        Border old = comp.getBorder();
        if (old == null)
            comp.setBorder(this);
        else
            comp.setBorder(BorderFactory.createCompoundBorder(this, old));
        return comp;
    //sample main
    public static void main(String[] args) {
        ExampleBorder panelB = new ExampleBorder(6, Color.BLUE);
        ExampleBorder compB = new ExampleBorder(2, Color.RED);
        JPanel cp = new JPanel(new GridLayout(2, 2, 1, 1));
        //cp.setBorder(BorderFactory.createEmptyBorder(2,2,2,2));
        panelB.wrap(cp);
        cp.add(compB.wrap(new JButton("alpha")));
        cp.add(compB.wrap(new JButton("beta")));
        cp.add(compB.wrap(new JButton("gamma")));
        cp.add(compB.wrap(new JButton("delta")));
        JFrame f = new JFrame("X");
        f.setDefaultCloseOperation(JFrame.EXIT_ON_CLOSE);
        f.setContentPane(cp);
        f.pack();
        f.setLocationRelativeTo(null);
        f.setVisible(true);