MakeFades.java Source code

Introduction

Here is the source code for MakeFades.java

Source

/*
 * Copyright (c) 2004 David Flanagan.  All rights reserved.
 * This code is from the book Java Examples in a Nutshell, 3nd Edition.
 * It is provided AS-IS, WITHOUT ANY WARRANTY either expressed or implied.
 * You may study, use, and modify it for any non-commercial purpose,
 * including teaching and use in open-source projects.
 * You may distribute it non-commercially as long as you retain this notice.
 * For a commercial use license, or to purchase the book, 
 * please visit http://www.davidflanagan.com/javaexamples3.
 */

import java.io.*;
import java.awt.*;
import java.awt.image.*;

/*
 * This program creates PNG images of the specified color that fade from fully
 * opaque to fully transparent. Images of this sort are useful in web design
 * where they can be used as background images and combined with background
 * colors to produce two-color fades. (IE6 does not support PNG transparency).
 * 
 * Images are produced in three sizes and with and 8 directions. The images are
 * written into the current directory and are given names of the form:
 * fade-to-color-speed-direction.png
 * 
 * color: the color name specified on the command line speed: slow (1024px),
 * medium (512px), fast(256px) direction: a compass point: N, E, S, W, NE, SE,
 * SW, NW
 * 
 * Invoke this program with a color name and three floating-point values
 * specifying the red, green, and blue components of the color.
 */
public class MakeFades {
    // A fast fade is a small image, and a slow fade is a large image
    public static final String[] sizeNames = { "fast", "medium", "slow" };

    public static final int[] sizes = { 256, 512, 1024 };

    // Direction names and coordinates
    public static final String[] directionNames = { "N", "E", "S", "W", "NE", "SE", "SW", "NW" };

    public static float[][] directions = { new float[] { 0f, 1f, 0f, 0f }, // North
            new float[] { 0f, 0f, 1f, 0f }, // East
            new float[] { 0f, 0f, 0f, 1f }, // South
            new float[] { 1f, 0f, 0f, 0f }, // West
            new float[] { 0f, 1f, 1f, 0f }, // Northeast
            new float[] { 0f, 0f, 1f, 1f }, // Southeast
            new float[] { 1f, 0f, 0f, 1f }, // Southwest
            new float[] { 1f, 1f, 0f, 0f } // Northwest
    };

    public static void main(String[] args) throws IOException, NumberFormatException {

        // Create from and to colors based on those arguments
        Color from = Color.RED; // transparent
        Color to = Color.BLACK; // opaque

        // Loop through the sizes and directions, and create an image for each
        for (int s = 0; s < sizes.length; s++) {
            for (int d = 0; d < directions.length; d++) {
                // This is the size of the image
                int size = sizes[s];

                // Create a GradientPaint for this direction and size
                Paint paint = new GradientPaint(directions[d][0] * size, directions[d][1] * size, from,
                        directions[d][2] * size, directions[d][3] * size, to);

                // Start with a blank image that supports transparency
                BufferedImage image = new BufferedImage(size, size, BufferedImage.TYPE_INT_ARGB);

                // Now use fill the image with our color gradient
                Graphics2D g = image.createGraphics();
                g.setPaint(paint);
                g.fillRect(0, 0, size, size);

                // This is the name of the file we'll write the image to
                File file = new File("fade-to-" + sizeNames[s] + "-" + directionNames[d] + ".png");

                // Save the image in PNG format using the javax.imageio API
                javax.imageio.ImageIO.write(image, "png", file);

                // Show the user our progress by printing the filename
                System.out.println(file);
            }
        }
    }
}