/*
* Copyright (C) 2013 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 com.android.server.accessibility;
import android.content.ContentResolver;
import android.content.Context;
import android.opengl.Matrix;
import android.os.IBinder;
import android.os.Parcel;
import android.os.RemoteException;
import android.os.ServiceManager;
import android.provider.Settings;
import android.util.Slog;
import android.view.accessibility.AccessibilityManager;
/**
* Utility methods for performing accessibility display adjustments.
*/
class DisplayAdjustmentUtils {
private static final String LOG_TAG = DisplayAdjustmentUtils.class.getSimpleName();
/** Matrix and offset used for converting color to gray-scale. */
private static final float[] GRAYSCALE_MATRIX = new float[] {
.2126f, .2126f, .2126f, 0,
.7152f, .7152f, .7152f, 0,
.0722f, .0722f, .0722f, 0,
0, 0, 0, 1
};
/**
* Matrix and offset used for luminance inversion. Represents a transform
* from RGB to YIQ color space, rotation around the Y axis by 180 degrees,
* transform back to RGB color space, and subtraction from 1. The last row
* represents a non-multiplied addition, see surfaceflinger's ProgramCache
* for full implementation details.
*/
private static final float[] INVERSION_MATRIX_VALUE_ONLY = new float[] {
0.402f, -0.598f, -0.599f, 0,
-1.174f, -0.174f, -1.175f, 0,
-0.228f, -0.228f, 0.772f, 0,
1, 1, 1, 1
};
/** Default inversion mode for display color correction. */
private static final int DEFAULT_DISPLAY_DALTONIZER =
AccessibilityManager.DALTONIZER_CORRECT_DEUTERANOMALY;
/**
* Returns whether the specified user with has any display color
* adjustments.
*/
public static boolean hasAdjustments(Context context, int userId) {
final ContentResolver cr = context.getContentResolver();
if (Settings.Secure.getIntForUser(cr,
Settings.Secure.ACCESSIBILITY_DISPLAY_INVERSION_ENABLED, 0, userId) != 0) {
return true;
}
if (Settings.Secure.getIntForUser(cr,
Settings.Secure.ACCESSIBILITY_DISPLAY_DALTONIZER_ENABLED, 0, userId) != 0) {
return true;
}
return false;
}
/**
* Applies the specified user's display color adjustments.
*/
public static void applyAdjustments(Context context, int userId) {
final ContentResolver cr = context.getContentResolver();
float[] colorMatrix = null;
if (Settings.Secure.getIntForUser(cr,
Settings.Secure.ACCESSIBILITY_DISPLAY_INVERSION_ENABLED, 0, userId) != 0) {
colorMatrix = multiply(colorMatrix, INVERSION_MATRIX_VALUE_ONLY);
}
if (Settings.Secure.getIntForUser(cr,
Settings.Secure.ACCESSIBILITY_DISPLAY_DALTONIZER_ENABLED, 0, userId) != 0) {
final int daltonizerMode = Settings.Secure.getIntForUser(cr,
Settings.Secure.ACCESSIBILITY_DISPLAY_DALTONIZER, DEFAULT_DISPLAY_DALTONIZER,
userId);
// Monochromacy isn't supported by the native Daltonizer.
if (daltonizerMode == AccessibilityManager.DALTONIZER_SIMULATE_MONOCHROMACY) {
colorMatrix = multiply(colorMatrix, GRAYSCALE_MATRIX);
setDaltonizerMode(AccessibilityManager.DALTONIZER_DISABLED);
} else {
setDaltonizerMode(daltonizerMode);
}
} else {
setDaltonizerMode(AccessibilityManager.DALTONIZER_DISABLED);
}
setColorTransform(colorMatrix);
}
private static float[] multiply(float[] matrix, float[] other) {
if (matrix == null) {
return other;
}
float[] result = new float[16];
Matrix.multiplyMM(result, 0, matrix, 0, other, 0);
return result;
}
/**
* Sets the surface flinger's Daltonization mode. This adjusts the color
* space to correct for or simulate various types of color blindness.
*
* @param mode new Daltonization mode
*/
private static void setDaltonizerMode(int mode) {
try {
final IBinder flinger = ServiceManager.getService("SurfaceFlinger");
if (flinger != null) {
final Parcel data = Parcel.obtain();
data.writeInterfaceToken("android.ui.ISurfaceComposer");
data.writeInt(mode);
flinger.transact(1014, data, null, 0);
data.recycle();
}
} catch (RemoteException ex) {
Slog.e(LOG_TAG, "Failed to set Daltonizer mode", ex);
}
}
/**
* Sets the surface flinger's color transformation as a 4x4 matrix. If the
* matrix is null, color transformations are disabled.
*
* @param m the float array that holds the transformation matrix, or null to
* disable transformation
*/
private static void setColorTransform(float[] m) {
try {
final IBinder flinger = ServiceManager.getService("SurfaceFlinger");
if (flinger != null) {
final Parcel data = Parcel.obtain();
data.writeInterfaceToken("android.ui.ISurfaceComposer");
if (m != null) {
data.writeInt(1);
for (int i = 0; i < 16; i++) {
data.writeFloat(m[i]);
}
} else {
data.writeInt(0);
}
flinger.transact(1015, data, null, 0);
data.recycle();
}
} catch (RemoteException ex) {
Slog.e(LOG_TAG, "Failed to set color transform", ex);
}
}
}