spotcolorspace.java

Java生成PDF Java生成PDF Java生成PDF

// $Id: SpotColorSpace.java,v 1.4 2005/07/29 11:32:50 mike Exp $

package org.faceless.pdf;

import java.awt.color.*;
import java.awt.*;

/**
 * <p>
 * A type of <tt>ColorSpace</tt> dealing with Separation ("Spot") Colors.
 * </p><p>
 * Spot colors are used to define an <i>exact</i> color in the printed
 * output. This is usually done by printing these colors using a matching
 * ink onto a separate film, ink which may be outside the gamut of the normal
 * CMYK printing process. Commonly used Spot colors include those from the
 * PANTONE&trade; and Focoltone&trade; range of colors.
 * </p><p>
 * Every Spot colorspace has a name, which is the name used by the printer
 * to identify the ink. Because not every output device may have the specified
 * ink available (displaying the PDF on screen for example), every Spot color
 * must have a "fallback" color specified as a process color (RGB or CMYK)
 * as well. Remembering that not every spot color can be reproduced in CMYK,
 * the fallback color is often just a close match.
 * </p><p>
 * Like normal colorspaces (RGB, CMYK and so on), different colors can be
 * specified within this space, although they will all be just a different
 * intensity  of the specified ink - ranging from zero (no ink is applied)
 * to one (the full intensity of the specified color is applied).
 * </p><p>
 * Here's an example showing how to use the PANTONE&trade; color "PANTONE
 * Reflex Blue" to print a line of text.
 * </p><pre>
 *   Color fallback = CYMKColorSpace.getColor(1.0, 0.72, 0, 0.06);
 *   SpotColorSpace blueink = new SpotColorSpace("PANTONE Reflex Blue CVC", fallback);
 *   Color logoblue = blueink.getColor(1);
 *
 *   PDFStyle style = new PDFStyle();
 *   style.setFillColor(logoblue);
 *   page.setStyle(style);
 *   page.drawText("This is in PANTONE Reflex Blue CVC", 100, 100);
 * </pre><p>
 * Note the three stages. First we create the fallback color, specified in
 * CMYK. As it happens this spot color is outside the gamut of the CMYK
 * colorspace, so our fallback is an approximation only. Then we create the
 * colorspace, and finally we select a color which is this ink at 100%
 * intensity. From there we can just use the color as normal.
 * </p>
 * In the PDF specification Spot color is referred to as a "Separation" color.
 * </p>
 * @since 1.1.5
 * @version $Revision: 1.4 $
 */
public class SpotColorSpace extends ColorSpace
{
    private org.faceless.pdf2.SpotColorSpace cspace;
    private Color fallback;

    /**
     * Create a new SpotColorSpace representing a single custom ink.
     * @param name the name of the ink
     * @param color the color to use as a fallback color if this ink is
     * not available. Must be from either an RGB, CMYK or Grayscale
     * ColorSpace, or an <tt>IllegalArgumentException</tt> is thrown.
     */
    public SpotColorSpace(String name, Color color)
    {
	super(color.getColorSpace().getType(), 1);
	cspace = new org.faceless.pdf2.SpotColorSpace(name, color);
        this.fallback = fallback;
    }

    public float[] toCIEXYZ(float[] comp)
    {
	return cspace.toCIEXYZ(comp);
    }
    public float[] fromCIEXYZ(float[] comp)
    {
	return cspace.fromCIEXYZ(comp);
    }
    public float[] toRGB(float[] comp)
    {
	return cspace.toRGB(comp);
    }
    public float[] fromRGB(float[] comp)
    {
	return cspace.fromRGB(comp);
    }

    /**
     * Get the name of this colorspace
     */
    public String getName()
    {
        return cspace.getName();
    }

    /**
     * Get the fallback color to use if this ink is not available
     */
    public Color getFallbackColor()
    {
	return fallback;
    }

    /**
     * A convenience method to return a color from this ColorSpace.
     * @param amt the intensity of the color. Any value between zero and
     * one, where zero means no ink at all and one means the full intensity.
     * If the number is outside this range, an <tt>IllegalArgumentException</tt>
     * is thrown
     * @throws IllegalArgumentException
     */
    public Color getColor(float amt)
    {
	return cspace.getColor(amt);
    }

    /**
     * A convenience method returning the color specified by the full intensity
     * of this colorspace. Equivalent to <tt>getColor(1)</tt>.
     */
    public Color getColor()
    {
	return cspace.getColor();
    }
}