Main.java Source code

Introduction

Here is the source code for Main.java

Source

//package com.java2s;
/*
 * Copyright 2015 The Android Open Source Project
 *
 * Licensed under the Apache License, Version 2.0 (the "License");
 * you may not use this file except in compliance with the License.
 * You may obtain a copy of the License at
 *
 *       http://www.apache.org/licenses/LICENSE-2.0
 *
 * Unless required by applicable law or agreed to in writing, software
 * distributed under the License is distributed on an "AS IS" BASIS,
 * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
 * See the License for the specific language governing permissions and
 * limitations under the License.
 */

import android.graphics.Color;

public class Main {
    /**
     * Convert the ARGB color to its HSL (hue-saturation-lightness) components.
     * <ul>
     * <li>outHsl[0] is Hue [0 .. 360)</li>
     * <li>outHsl[1] is Saturation [0...1]</li>
     * <li>outHsl[2] is Lightness [0...1]</li>
     * </ul>
     *
     * @param color  the ARGB color to convert. The alpha component is ignored
     * @param outHsl 3-element array which holds the resulting HSL components
     */
    public static void colorToHSL(int color, float[] outHsl) {
        RGBToHSL(Color.red(color), Color.green(color), Color.blue(color), outHsl);
    }

    /**
     * Convert RGB components to HSL (hue-saturation-lightness).
     * <ul>
     * <li>outHsl[0] is Hue [0 .. 360)</li>
     * <li>outHsl[1] is Saturation [0...1]</li>
     * <li>outHsl[2] is Lightness [0...1]</li>
     * </ul>
     *
     * @param r      red component value [0..255]
     * @param g      green component value [0..255]
     * @param b      blue component value [0..255]
     * @param outHsl 3-element array which holds the resulting HSL components
     */
    public static void RGBToHSL(int r, int g, int b, float[] outHsl) {
        final float rf = r / 255f;
        final float gf = g / 255f;
        final float bf = b / 255f;

        final float max = Math.max(rf, Math.max(gf, bf));
        final float min = Math.min(rf, Math.min(gf, bf));
        final float deltaMaxMin = max - min;

        float h, s;
        float l = (max + min) / 2f;

        if (max == min) {
            // Monochromatic
            h = s = 0f;
        } else {
            if (max == rf) {
                h = ((gf - bf) / deltaMaxMin) % 6f;
            } else if (max == gf) {
                h = ((bf - rf) / deltaMaxMin) + 2f;
            } else {
                h = ((rf - gf) / deltaMaxMin) + 4f;
            }

            s = deltaMaxMin / (1f - Math.abs(2f * l - 1f));
        }

        h = (h * 60f) % 360f;
        if (h < 0) {
            h += 360f;
        }

        outHsl[0] = constrain(h, 0f, 360f);
        outHsl[1] = constrain(s, 0f, 1f);
        outHsl[2] = constrain(l, 0f, 1f);
    }

    private static float constrain(float amount, float low, float high) {
        return amount < low ? low : (amount > high ? high : amount);
    }

    private static int constrain(int amount, int low, int high) {
        return amount < low ? low : (amount > high ? high : amount);
    }
}