Author: dsvyatobatsko Date: 2008-02-05 11:42:16 -0500 (Tue, 05 Feb 2008) New Revision: 5832 Added: trunk/sandbox/ui/progressBAR/src/main/java/org/richfaces/renderkit/html/images/ColorUtils.java Log: Added: trunk/sandbox/ui/progressBAR/src/main/java/org/richfaces/renderkit/html/images/ColorUtils.java =================================================================== --- trunk/sandbox/ui/progressBAR/src/main/java/org/richfaces/renderkit/html/images/ColorUtils.java (rev 0) +++ trunk/sandbox/ui/progressBAR/src/main/java/org/richfaces/renderkit/html/images/ColorUtils.java 2008-02-05 16:42:16 UTC (rev 5832) @@ -0,0 +1,208 @@ +/** + * License Agreement. + * + * JBoss RichFaces - Ajax4jsf Component Library + * + * Copyright (C) 2007 Exadel, Inc. + * + * This library is free software; you can redistribute it and/or + * modify it under the terms of the GNU Lesser General Public + * License version 2.1 as published by the Free Software Foundation. + * + * This library 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 + * Lesser General Public License for more details. + * + * You should have received a copy of the GNU Lesser General Public + * License along with this library; if not, write to the Free Software + * Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA + */ +package org.richfaces.renderkit.html.images; + +import java.awt.Color; + +/** + * Utility methods that are useful for color processing. + * + * @author carcasser + */ +public abstract class ColorUtils { + + /** + * Converts the components of a color, as specified by the default RGB + * model, to an equivalent set of values for hue, saturation, and + * lightness that are the three components of the HSL model. + * + * @param r the red component of the color + * @param g the green component of the color + * @param b the blue component of the color + * @return an array of three elements containing the hue, saturation, + * and lightness (in that order), of the color with + * the indicated red, green, and blue components. + */ + public static float[] RGBtoHSL(int r, int g, int b) { + float varR = (r / 255f); + float varG = (g / 255f); + float varB = (b / 255f); + + float varMin = Math.min(varR, Math.min(varG, varB)); //Min value of RGB + float varMax = Math.max(varR, Math.max(varG, varB)); //Max value of RGB + float delMax = varMax - varMin; //Delta RGB value + + float h = 0; + float s = 0; + float l = (varMax + varMin) / 2; + + if(delMax == 0 || l == 0) { + s = 0; + } else if (l == 1) { + s = 1; + } else if(l <= 0.5) { + s = delMax / (2 * (1 - l)); + } else if(l > 0.5) { + s = delMax / (2 * l); + } + + if(delMax == 0) { + h = 0; + } else if (varMax == varR && g >= b) { + h = 60 * (varG - varB) / delMax + 0; + } else if (varMax == varR && varG < b) { + h = 60 * (varG - varB) / delMax + 360; + } else if (varMax == varG) { + h = 60 * (varB - varR) / delMax + 120; + } else if (varMax == varB) { + h = 60 * (varR - varG) / delMax + 240; + } + + return new float[] { h, s, l }; + } + + /** + * Converts the components of a color, as specified by the HSL + * model, to an equivalent set of values for the default RGB model. + * <p> + * The <code>saturation</code> and <code>lightness</code> components + * should be floating-point values between zero and one + * (numbers in the range 0.0-1.0). The <code>hue</code> component + * can be any floating-point number. The floor of this number is + * subtracted from it to create a fraction between 0 and 1. This + * fractional number is then multiplied by 360 to produce the hue + * angle in the HSB color model. + * @param h the hue component of the color + * @param s the saturation of the color + * @param l the lightness of the color + * @return the RGB value of the color with the indicated hue, + * saturation, and lightness + */ + public static Color HSLtoRGB(float h, float s, float l) { + float q; + if (l < 0.5) { + q = l * (1 + s); + } else { + q = l + s - (l * s); + } + + float p = 2 * l - q; + float hNorm = h / 360; + + float tR = hNorm + 1f/3f; + float tG = hNorm; + float tB = hNorm - 1f/3f; + + float r = tC2C(tR, p, q); + float g = tC2C(tG, p, q); + float b = tC2C(tB, p, q); + + return new Color(r, g, b); + } + + private static float tC2C(float tC, float p, float q) + { + float retVal; + + if (tC < 0) { + tC += 1; + } + + if (tC > 1) { + tC -= 1; + } + + if ((6 * tC) < 1) { + retVal = (p + (q - p) * 6 * tC); + } else if ((2 * tC) < 1) { + retVal = q; + } else if ((3 * tC) < 2) { + retVal = (p + (q - p) * 6 * (2f / 3f - tC)); + } else { + retVal = p; + } + + return retVal; + } + + /** + * Increases/decreases brightness of the given color by the specified <code>difference</code>. + * <p> + * The <code>difference</code> values in the range (-1.0, 1.0): 1.0 - the brightest value; + * -1.0 - the dimmest value. + * + * @param c color to adjust + * @param difference value to be added to the current brightness + * + * @return a new <code>Color</code> instance with increased/decreased brightness by specified <code>difference</code> + * @throws IllegalArgumentException if difference is outside of the range -1.0 to 1.0, inclusive + */ + public static Color adjustBrightness(Color c, float difference) { + if (difference < -1.0 || difference > 1.0) { + throw new IllegalArgumentException("Difference parameter outside of expected range: " + + "Difference parameter should be floating-point values between -1 and 1"); + } + + float[] hsb = Color.RGBtoHSB(c.getRed(), c.getGreen(), c.getBlue(), null); + float brightness = Math.min(1.0f, Math.max(0.0f, hsb[2] + difference)); + return new Color(Color.HSBtoRGB(hsb[0], hsb[1], brightness)); + } + + /** + * Increases/decreases lightness of the given color by the specified <code>difference</code>. + * <p> + * The <code>difference</code> values in the range (-1.0, 1.0): 1.0 - the lightest value; + * -1.0 - on the contrary. + * + * @param c color to adjust + * @param difference value to be added to the current lightness + * + * @return a new <code>Color</code> instance with increased/decreased lightness by specified <code>difference</code> + * @throws IllegalArgumentException if difference is outside of the range -1.0 to 1.0, inclusive + */ + public static Color adjustLightness(Color c, float difference) { + if (difference < -1.0 || difference > 1.0) { + throw new IllegalArgumentException("Difference parameter outside of expected range: " + + "Difference parameter should be floating-point values between -1 and 1"); + } + + float[] hsl = RGBtoHSL(c.getRed(), c.getGreen(), c.getBlue()); + float lightness = Math.min(1.0f, Math.max(0.0f, hsl[2] + difference)); + return HSLtoRGB(hsl[0], hsl[1], lightness); + } + + /** + * Overwrites alpha value for given color. + * + * @param c color to overwrite + * @param alpha a new value of alpha + * @return a new <code>Color</code> object with a new specified alpha value + */ + public static Color overwriteAlpha(Color c, float alpha) { + Color retVal = c; + if (c != null) { + retVal = new Color(c.getRed(), c.getGreen(), c.getBlue(), + (int) (alpha * 255 + 0.5)); + } + return retVal; + } + +} Property changes on: trunk/sandbox/ui/progressBAR/src/main/java/org/richfaces/renderkit/html/images/ColorUtils.java ___________________________________________________________________ Name: svn:mime-type + text/plain Name: svn:keywords + Author Id Revision Date Name: svn:eol-style + native