DeviceRgb.java

/*
    This file is part of the iText (R) project.
    Copyright (c) 1998-2025 Apryse Group NV
    Authors: Apryse Software.

    This program is offered under a commercial and under the AGPL license.
    For commercial licensing, contact us at https://itextpdf.com/sales.  For AGPL licensing, see below.

    AGPL licensing:
    This program is free software: you can redistribute it and/or modify
    it under the terms of the GNU Affero General Public License as published by
    the Free Software Foundation, either version 3 of the License, or
    (at your option) any later version.

    This program is distributed in the hope that it will be useful,
    but WITHOUT ANY WARRANTY; without even the implied warranty of
    MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
    GNU Affero General Public License for more details.

    You should have received a copy of the GNU Affero General Public License
    along with this program.  If not, see <https://www.gnu.org/licenses/>.
 */
package com.itextpdf.kernel.colors;

import com.itextpdf.io.logs.IoLogMessageConstant;
import com.itextpdf.commons.utils.MessageFormatUtil;
import com.itextpdf.kernel.pdf.colorspace.PdfDeviceCs;
import org.slf4j.Logger;
import org.slf4j.LoggerFactory;

/**
 * Color space to specify colors according to RGB color model.
 */
public class DeviceRgb extends Color {
    /**
     * Predefined black DeviceRgb color
     */
    public static final Color BLACK = new DeviceRgb(0, 0, 0);

    /**
     * Predefined white DeviceRgb color
     */
    public static final Color WHITE = new DeviceRgb(255, 255, 255);

    /**
     * Predefined red DeviceRgb color
     */
    public static final Color RED = new DeviceRgb(255, 0, 0);

    /**
     * Predefined green DeviceRgb color
     */
    public static final Color GREEN = new DeviceRgb(0, 255, 0);

    /**
     * Predefined blue  DeviceRgb color
     */
    public static final Color BLUE = new DeviceRgb(0, 0, 255);


    /**
     * Creates DeviceRgb color by intensities of red, green and blue colorants.
     * The intensities are considered to be in [0, 255] gap, if not,
     * the intensity will be considered as 255 (when colorant's value is bigger than 255)
     * or 0 (when colorant's value is less than 0).
     *
     * @param r the intensity of red colorant
     * @param g the intensity of green colorant
     * @param b the intensity of blue colorant
     */
    public DeviceRgb(int r, int g, int b) {
        this(r / 255f, g / 255f, b / 255f);
    }

    /**
     * Creates DeviceRgb color by intensities of red, green and blue colorants.
     * The intensities are considered to be in [0, 1] interval, if not,
     * the intensity will be considered as 1 (when colorant's value is bigger than 1)
     * or 0 (when colorant's value is less than 0).
     *
     * @param r the intensity of red colorant
     * @param g the intensity of green colorant
     * @param b the intensity of blue colorant
     */
    public DeviceRgb(float r, float g, float b) {
        super(new PdfDeviceCs.Rgb(), new float[]{
                r > 1 ? 1 : (r > 0 ? r : 0),
                g > 1 ? 1 : (g > 0 ? g : 0),
                b > 1 ? 1 : (b > 0 ? b : 0)
        });
        if (r > 1 || r < 0 || g > 1 || g < 0 || b > 1 || b < 0) {
            Logger LOGGER = LoggerFactory.getLogger(DeviceRgb.class);
            LOGGER.warn(IoLogMessageConstant.COLORANT_INTENSITIES_INVALID);
        }
    }

    // Android-Conversion-Skip-Block-Start (java.awt library isn't available on Android)
    /**
     * Create DeviceRGB color from R, G, B values of java.awt.Color
     * <p>
     * Note, that alpha chanel is ignored,  but opacity still can be achieved
     * in some places by using 'setOpacity' method or 'TransparentColor' class.
     *
     * @param color the color which RGB values are used
     */
    public DeviceRgb(java.awt.Color color) {
        this(color.getRed(), color.getGreen(), color.getBlue());
        if (color.getAlpha() != 255) {
            Logger LOGGER = LoggerFactory.getLogger(DeviceRgb.class);
            LOGGER.warn(MessageFormatUtil.format(IoLogMessageConstant.COLOR_ALPHA_CHANNEL_IS_IGNORED, color.getAlpha()));
        }
    }
    // Android-Conversion-Skip-Block-End

    /**
     * Creates DeviceRgb color with all colorants intensities initialised as zeroes.
     */
    public DeviceRgb() {
        this(0f, 0f, 0f);
    }

    /**
     * Returns {@link DeviceRgb DeviceRgb} color which is lighter than given one
     * @param rgbColor the DeviceRgb color to be made lighter
     *
     * @return lighter color
     */
    public static DeviceRgb makeLighter(DeviceRgb rgbColor) {
        float r = rgbColor.getColorValue()[0];
        float g = rgbColor.getColorValue()[1];
        float b = rgbColor.getColorValue()[2];

        float v = Math.max(r, Math.max(g, b));

        if (v == 0f) {
            return new DeviceRgb(0x54, 0x54, 0x54);
        }

        float multiplier = Math.min(1f, v + 0.33f) / v;

        r = multiplier * r;
        g = multiplier * g;
        b = multiplier * b;
        return new DeviceRgb(r, g, b);
    }

    /**
     * Returns {@link DeviceRgb DeviceRgb} color which is darker than given one
     * @param rgbColor the DeviceRgb color to be made darker
     *
     * @return darker color
     */
    public static DeviceRgb makeDarker(DeviceRgb rgbColor) {
        float r = rgbColor.getColorValue()[0];
        float g = rgbColor.getColorValue()[1];
        float b = rgbColor.getColorValue()[2];

        float v = Math.max(r, Math.max(g, b));

        float multiplier = Math.max(0f, (v - 0.33f) / v);

        r = multiplier * r;
        g = multiplier * g;
        b = multiplier * b;
        return new DeviceRgb(r, g, b);
    }
}