Merge "AOD: Fix contrast calculation" (23a96af5) · Commits · e / os / android_frameworks_base

core/java/com/android/internal/util/NotificationColorUtil.java

+146 −8

Original line number	Diff line number	Diff line
		@@ -303,17 +303,17 @@ public class NotificationColorUtil {
		return color;
		}

		double[] lab = new double[3];
		ColorUtilsFromCompat.colorToLAB(findFg ? fg : bg, lab);
		float[] hsl = new float[3];
		ColorUtilsFromCompat.colorToHSL(findFg ? fg : bg, hsl);

		double low = lab[0], high = 100;
		final double a = lab[1], b = lab[2];
		float low = hsl[2], high = 1;
		for (int i = 0; i < 15 && high - low > 0.00001; i++) {
		final double l = (low + high) / 2;
		final float l = (low + high) / 2;
		hsl[2] = l;
		if (findFg) {
		fg = ColorUtilsFromCompat.LABToColor(l, a, b);
		fg = ColorUtilsFromCompat.HSLToColor(hsl);
		} else {
		bg = ColorUtilsFromCompat.LABToColor(l, a, b);
		bg = ColorUtilsFromCompat.HSLToColor(hsl);
		}
		if (ColorUtilsFromCompat.calculateContrast(fg, bg) > minRatio) {
		high = l;
		@@ -321,7 +321,7 @@ public class NotificationColorUtil {
		low = l;
		}
		}
		return ColorUtilsFromCompat.LABToColor(high, a, b);
		return findFg ? fg : bg;
		}

		public static int ensureTextContrastOnBlack(int color) {
		@@ -764,6 +764,10 @@ public class NotificationColorUtil {
		return amount < low ? low : (amount > high ? high : amount);
		}

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

		private static double pivotXyzComponent(double component) {
		return component > XYZ_EPSILON
		? Math.pow(component, 1 / 3.0)
		@@ -779,5 +783,139 @@ public class NotificationColorUtil {
		return result;
		}

		/**
		* Convert HSL (hue-saturation-lightness) components to a RGB color.
		* <ul>
		* <li>hsl[0] is Hue [0 .. 360)</li>
		* <li>hsl[1] is Saturation [0...1]</li>
		* <li>hsl[2] is Lightness [0...1]</li>
		* </ul>
		* If hsv values are out of range, they are pinned.
		*
		* @param hsl 3-element array which holds the input HSL components
		* @return the resulting RGB color
		*/
		@ColorInt
		public static int HSLToColor(@NonNull float[] hsl) {
		final float h = hsl[0];
		final float s = hsl[1];
		final float l = hsl[2];

		final float c = (1f - Math.abs(2 * l - 1f)) * s;
		final float m = l - 0.5f * c;
		final float x = c * (1f - Math.abs((h / 60f % 2f) - 1f));

		final int hueSegment = (int) h / 60;

		int r = 0, g = 0, b = 0;

		switch (hueSegment) {
		case 0:
		r = Math.round(255 * (c + m));
		g = Math.round(255 * (x + m));
		b = Math.round(255 * m);
		break;
		case 1:
		r = Math.round(255 * (x + m));
		g = Math.round(255 * (c + m));
		b = Math.round(255 * m);
		break;
		case 2:
		r = Math.round(255 * m);
		g = Math.round(255 * (c + m));
		b = Math.round(255 * (x + m));
		break;
		case 3:
		r = Math.round(255 * m);
		g = Math.round(255 * (x + m));
		b = Math.round(255 * (c + m));
		break;
		case 4:
		r = Math.round(255 * (x + m));
		g = Math.round(255 * m);
		b = Math.round(255 * (c + m));
		break;
		case 5:
		case 6:
		r = Math.round(255 * (c + m));
		g = Math.round(255 * m);
		b = Math.round(255 * (x + m));
		break;
		}

		r = constrain(r, 0, 255);
		g = constrain(g, 0, 255);
		b = constrain(b, 0, 255);

		return Color.rgb(r, g, b);
		}

		/**
		* 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(@ColorInt int color, @NonNull 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(@IntRange(from = 0x0, to = 0xFF) int r,
		@IntRange(from = 0x0, to = 0xFF) int g, @IntRange(from = 0x0, to = 0xFF) int b,
		@NonNull 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);
		}

		}
		}