A demonstration of Java2D transformations

[Java Tip]

Code:

import java.awt.BasicStroke;
import java.awt.Color;
import java.awt.Font;
import java.awt.GradientPaint;
import java.awt.Graphics;
import java.awt.Graphics2D;
import java.awt.Paint;
import java.awt.Rectangle;
import java.awt.Shape;
import java.awt.TexturePaint;
import java.awt.font.GlyphVector;
import java.awt.geom.AffineTransform;
import java.awt.image.BufferedImage;
import java.awt.event.WindowAdapter;
import java.awt.event.WindowEvent;

import javax.swing.JFrame;
import javax.swing.JPanel;

/** A demonstration of Java2D transformations */
public class Paints extends JPanel {
  static final int WIDTH = 800, HEIGHT = 375; // Size of our example

  public String getName() {
    return "Paints";
  }

  public int getWidth() {
    return WIDTH;
  }

  public int getHeight() {
    return HEIGHT;
  }

  /** Draw the example */
  public void paint(Graphics g1) {
    Graphics2D g = (Graphics2D) g1;
    // Paint the entire background using a GradientPaint.
    // The background color varies diagonally from deep red to pale blue
    g.setPaint(new GradientPaint(0, 0, new Color(150, 0, 0), WIDTH, HEIGHT,
        new Color(200, 200, 255)));
    g.fillRect(0, 0, WIDTH, HEIGHT); // fill the background

    // Use a different GradientPaint to draw a box.
    // This one alternates between deep opaque green and transparent green.
    // Note: the 4th arg to Color() constructor specifies color opacity
    g.setPaint(new GradientPaint(0, 0, new Color(0, 150, 0), 20, 20,
        new Color(0, 150, 0, 0), true));
    g.setStroke(new BasicStroke(15)); // use wide lines
    g.drawRect(25, 25, WIDTH - 50, HEIGHT - 50); // draw the box

    // The glyphs of fonts can be used as Shape objects, which enables
    // us to use Java2D techniques with letters Just as we would with
    // any other shape. Here we get some letter shapes to draw.
    Font font = new Font("Serif", Font.BOLD, 10); // a basic font
    Font bigfont = // a scaled up version
    font.deriveFont(AffineTransform.getScaleInstance(30.0, 30.0));
    GlyphVector gv = bigfont.createGlyphVector(g.getFontRenderContext(),
        "JAV");
    Shape jshape = gv.getGlyphOutline(0); // Shape of letter J
    Shape ashape = gv.getGlyphOutline(1); // Shape of letter A
    Shape vshape = gv.getGlyphOutline(2); // Shape of letter V

    // We're going to outline the letters with a 5-pixel wide line
    g.setStroke(new BasicStroke(5.0f));

    // We're going to fake shadows for the letters using the
    // following Paint and AffineTransform objects
    Paint shadowPaint = new Color(0, 0, 0, 100); // Translucent black
    AffineTransform shadowTransform = AffineTransform.getShearInstance(
        -1.0, 0.0); // Shear to the right
    shadowTransform.scale(1.0, 0.5); // Scale height by 1/2

    // Move to the baseline of our first letter
    g.translate(65, 270);

    // Draw the shadow of the J shape
    g.setPaint(shadowPaint);
    g.translate(15, 20); // Compensate for the descender of the J
    // transform the J into the shape of its shadow, and fill it
    g.fill(shadowTransform.createTransformedShape(jshape));
    g.translate(-15, -20); // Undo the translation above

    // Now fill the J shape with a solid (and opaque) color
    g.setPaint(Color.blue); // Fill with solid, opaque blue
    g.fill(jshape); // Fill the shape
    g.setPaint(Color.black); // Switch to solid black
    g.draw(jshape); // And draw the outline of the J

    // Now draw the A shadow
    g.translate(75, 0); // Move to the right
    g.setPaint(shadowPaint); // Set shadow color
    g.fill(shadowTransform.createTransformedShape(ashape)); // draw shadow

    // Draw the A shape using a solid transparent color
    g.setPaint(new Color(0, 255, 0, 125)); // Transparent green as paint
    g.fill(ashape); // Fill the shape
    g.setPaint(Color.black); // Switch to solid back
    g.draw(ashape); // Draw the outline

    // Move to the right and draw the shadow of the letter V
    g.translate(175, 0);
    g.setPaint(shadowPaint);
    g.fill(shadowTransform.createTransformedShape(vshape));

    // We're going to fill the next letter using a TexturePaint, which
    // repeatedly tiles an image. The first step is to obtain the image.
    // We could load it from an image file, but here we create it
    // ourselves by drawing a into an off-screen image. Note that we use
    // a GradientPaint to fill the off-screen image, so the fill pattern
    // combines features of both Paint classes.
    BufferedImage tile = // Create an image
    new BufferedImage(50, 50, BufferedImage.TYPE_INT_RGB);
    Graphics2D tg = tile.createGraphics(); // Get its Graphics for drawing
    tg.setColor(Color.pink);
    tg.fillRect(0, 0, 50, 50); // Fill tile background with pink
    tg.setPaint(new GradientPaint(40, 0, Color.green, // diagonal gradient
        0, 40, Color.gray)); // green to gray
    tg.fillOval(5, 5, 40, 40); // Draw a circle with this gradient

    // Use this new tile to create a TexturePaint and fill the letter V
    g.setPaint(new TexturePaint(tile, new Rectangle(0, 0, 50, 50)));
    g.fill(vshape); // Fill letter shape
    g.setPaint(Color.black); // Switch to solid black
    g.draw(vshape); // Draw outline of letter

    // Move to the right and draw the shadow of the final A
    g.translate(160, 0);
    g.setPaint(shadowPaint);
    g.fill(shadowTransform.createTransformedShape(ashape));


    g.fill(ashape); // Fill letter A
    g.setPaint(Color.black); // Revert to solid black
    g.draw(ashape); // Draw the outline of the A
  }
  public static void main(String[] a) {
    JFrame f = new JFrame();
    f.addWindowListener(new WindowAdapter() {
      public void windowClosing(WindowEvent e) {
        System.exit(0);
      }
    });
    f.setContentPane(new Paints());
    f.setSize(800,375);
    f.setVisible(true);
  }
}