/*
* Copyright (C) 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.
*/
package android.support.v4.graphics;
import android.graphics.Color;
import android.support.v4.graphics.ColorUtils;
import android.test.AndroidTestCase;
import java.util.ArrayList;
/**
* @hide
*/
public class ColorUtilsTest extends AndroidTestCase {
// 0.5% of the max value
private static final float ALLOWED_OFFSET_HUE = 360 * 0.005f;
private static final float ALLOWED_OFFSET_SATURATION = 0.005f;
private static final float ALLOWED_OFFSET_LIGHTNESS = 0.005f;
private static final int ALLOWED_OFFSET_RGB_COMPONENT = 2;
private static final ArrayList<TestEntry> sEntryList = new ArrayList<>();
static {
sEntryList.add(new TestEntry(Color.BLACK).setHsl(0f, 0f, 0f));
sEntryList.add(new TestEntry(Color.WHITE).setHsl(0f, 0f, 1f));
sEntryList.add(new TestEntry(Color.BLUE).setHsl(240f, 1f, 0.5f));
sEntryList.add(new TestEntry(Color.GREEN).setHsl(120f, 1f, 0.5f));
sEntryList.add(new TestEntry(Color.RED).setHsl(0f, 1f, 0.5f));
sEntryList.add(new TestEntry(Color.CYAN).setHsl(180f, 1f, 0.5f));
sEntryList.add(new TestEntry(0x2196F3).setHsl(207f, 0.9f, 0.54f));
sEntryList.add(new TestEntry(0xD1C4E9).setHsl(261f, 0.46f, 0.84f));
sEntryList.add(new TestEntry(0x311B92).setHsl(251.09f, 0.687f, 0.339f));
}
public void testToHSL() {
for (TestEntry entry : sEntryList) {
testColorToHSL(entry.rgb, entry.hsl);
}
}
public void testFromHSL() {
for (TestEntry entry : sEntryList) {
testHSLToColor(entry.hsl, entry.rgb);
}
}
public void testToHslLimits() {
final float[] hsl = new float[3];
for (TestEntry entry : sEntryList) {
ColorUtils.colorToHSL(entry.rgb, hsl);
assertTrue(hsl[0] >= 0f && hsl[0] <= 360f);
assertTrue(hsl[1] >= 0f && hsl[1] <= 1f);
assertTrue(hsl[2] >= 0f && hsl[2] <= 1f);
}
}
private static void assertClose(String message, float expected, float actual,
float allowedOffset) {
StringBuilder sb = new StringBuilder(message);
sb.append(". Expected: ").append(expected).append(". Actual: ").append(actual);
assertTrue(sb.toString(), Math.abs(expected - actual) <= allowedOffset);
}
private static void assertClose(String message, int expected, int actual,
int allowedOffset) {
StringBuilder sb = new StringBuilder(message);
sb.append(". Expected: ").append(expected).append(". Actual: ").append(actual);
assertTrue(sb.toString(), Math.abs(expected - actual) <= allowedOffset);
}
private static void testColorToHSL(int color, float[] expectedHsl) {
float[] actualHSL = new float[3];
ColorUtils.colorToHSL(color, actualHSL);
assertClose("Hue not within offset", expectedHsl[0], actualHSL[0],
ALLOWED_OFFSET_HUE);
assertClose("Saturation not within offset", expectedHsl[1], actualHSL[1],
ALLOWED_OFFSET_SATURATION);
assertClose("Lightness not within offset", expectedHsl[2], actualHSL[2],
ALLOWED_OFFSET_LIGHTNESS);
}
private static void testHSLToColor(float[] hsl, int expectedRgb) {
final int actualRgb = ColorUtils.HSLToColor(hsl);
assertClose("Red not within offset",
Color.red(expectedRgb), Color.red(actualRgb), ALLOWED_OFFSET_RGB_COMPONENT);
assertClose("Green not within offset",
Color.green(expectedRgb), Color.green(actualRgb), ALLOWED_OFFSET_RGB_COMPONENT);
assertClose("Blue not within offset",
Color.blue(expectedRgb), Color.blue(actualRgb), ALLOWED_OFFSET_RGB_COMPONENT);
}
private static class TestEntry {
final int rgb;
final float[] hsl = new float[3];
TestEntry(int rgb) {
this.rgb = rgb;
}
TestEntry setHsl(float h, float s, float l) {
hsl[0] = h;
hsl[1] = s;
hsl[2] = l;
return this;
}
}
}