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      1 /*
      2  * Copyright (C) 2013 The Android Open Source Project
      3  *
      4  * Licensed under the Apache License, Version 2.0 (the "License");
      5  * you may not use this file except in compliance with the License.
      6  * You may obtain a copy of the License at
      7  *
      8  *      http://www.apache.org/licenses/LICENSE-2.0
      9  *
     10  * Unless required by applicable law or agreed to in writing, software
     11  * distributed under the License is distributed on an "AS IS" BASIS,
     12  * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
     13  * See the License for the specific language governing permissions and
     14  * limitations under the License.
     15  */
     16 
     17 package com.android.server.accessibility;
     18 
     19 import android.content.ContentResolver;
     20 import android.content.Context;
     21 import android.opengl.Matrix;
     22 import android.os.IBinder;
     23 import android.os.Parcel;
     24 import android.os.RemoteException;
     25 import android.os.ServiceManager;
     26 import android.provider.Settings;
     27 import android.util.Slog;
     28 import android.view.accessibility.AccessibilityManager;
     29 
     30 /**
     31  * Utility methods for performing accessibility display adjustments.
     32  */
     33 class DisplayAdjustmentUtils {
     34     private static final String LOG_TAG = DisplayAdjustmentUtils.class.getSimpleName();
     35 
     36     /** Matrix and offset used for converting color to gray-scale. */
     37     private static final float[] GRAYSCALE_MATRIX = new float[] {
     38         .2126f, .2126f, .2126f, 0,
     39         .7152f, .7152f, .7152f, 0,
     40         .0722f, .0722f, .0722f, 0,
     41              0,      0,      0, 1
     42     };
     43 
     44     /**
     45      * Matrix and offset used for luminance inversion. Represents a transform
     46      * from RGB to YIQ color space, rotation around the Y axis by 180 degrees,
     47      * transform back to RGB color space, and subtraction from 1. The last row
     48      * represents a non-multiplied addition, see surfaceflinger's ProgramCache
     49      * for full implementation details.
     50      */
     51     private static final float[] INVERSION_MATRIX_VALUE_ONLY = new float[] {
     52         0.402f, -0.598f, -0.599f, 0,
     53        -1.174f, -0.174f, -1.175f, 0,
     54        -0.228f, -0.228f,  0.772f, 0,
     55              1,       1,       1, 1
     56     };
     57 
     58     /** Default inversion mode for display color correction. */
     59     private static final int DEFAULT_DISPLAY_DALTONIZER =
     60             AccessibilityManager.DALTONIZER_CORRECT_DEUTERANOMALY;
     61 
     62     /**
     63      * Returns whether the specified user with has any display color
     64      * adjustments.
     65      */
     66     public static boolean hasAdjustments(Context context, int userId) {
     67         final ContentResolver cr = context.getContentResolver();
     68 
     69         if (Settings.Secure.getIntForUser(cr,
     70                 Settings.Secure.ACCESSIBILITY_DISPLAY_INVERSION_ENABLED, 0, userId) != 0) {
     71             return true;
     72         }
     73 
     74         if (Settings.Secure.getIntForUser(cr,
     75                 Settings.Secure.ACCESSIBILITY_DISPLAY_DALTONIZER_ENABLED, 0, userId) != 0) {
     76             return true;
     77         }
     78 
     79         return false;
     80     }
     81 
     82     /**
     83      * Applies the specified user's display color adjustments.
     84      */
     85     public static void applyAdjustments(Context context, int userId) {
     86         final ContentResolver cr = context.getContentResolver();
     87         float[] colorMatrix = null;
     88 
     89         if (Settings.Secure.getIntForUser(cr,
     90                 Settings.Secure.ACCESSIBILITY_DISPLAY_INVERSION_ENABLED, 0, userId) != 0) {
     91             colorMatrix = multiply(colorMatrix, INVERSION_MATRIX_VALUE_ONLY);
     92         }
     93 
     94         if (Settings.Secure.getIntForUser(cr,
     95                 Settings.Secure.ACCESSIBILITY_DISPLAY_DALTONIZER_ENABLED, 0, userId) != 0) {
     96             final int daltonizerMode = Settings.Secure.getIntForUser(cr,
     97                     Settings.Secure.ACCESSIBILITY_DISPLAY_DALTONIZER, DEFAULT_DISPLAY_DALTONIZER,
     98                     userId);
     99             // Monochromacy isn't supported by the native Daltonizer.
    100             if (daltonizerMode == AccessibilityManager.DALTONIZER_SIMULATE_MONOCHROMACY) {
    101                 colorMatrix = multiply(colorMatrix, GRAYSCALE_MATRIX);
    102                 setDaltonizerMode(AccessibilityManager.DALTONIZER_DISABLED);
    103             } else {
    104                 setDaltonizerMode(daltonizerMode);
    105             }
    106         } else {
    107             setDaltonizerMode(AccessibilityManager.DALTONIZER_DISABLED);
    108         }
    109 
    110         setColorTransform(colorMatrix);
    111     }
    112 
    113     private static float[] multiply(float[] matrix, float[] other) {
    114         if (matrix == null) {
    115             return other;
    116         }
    117         float[] result = new float[16];
    118         Matrix.multiplyMM(result, 0, matrix, 0, other, 0);
    119         return result;
    120     }
    121 
    122     /**
    123      * Sets the surface flinger's Daltonization mode. This adjusts the color
    124      * space to correct for or simulate various types of color blindness.
    125      *
    126      * @param mode new Daltonization mode
    127      */
    128     private static void setDaltonizerMode(int mode) {
    129         try {
    130             final IBinder flinger = ServiceManager.getService("SurfaceFlinger");
    131             if (flinger != null) {
    132                 final Parcel data = Parcel.obtain();
    133                 data.writeInterfaceToken("android.ui.ISurfaceComposer");
    134                 data.writeInt(mode);
    135                 flinger.transact(1014, data, null, 0);
    136                 data.recycle();
    137             }
    138         } catch (RemoteException ex) {
    139             Slog.e(LOG_TAG, "Failed to set Daltonizer mode", ex);
    140         }
    141     }
    142 
    143     /**
    144      * Sets the surface flinger's color transformation as a 4x4 matrix. If the
    145      * matrix is null, color transformations are disabled.
    146      *
    147      * @param m the float array that holds the transformation matrix, or null to
    148      *            disable transformation
    149      */
    150     private static void setColorTransform(float[] m) {
    151         try {
    152             final IBinder flinger = ServiceManager.getService("SurfaceFlinger");
    153             if (flinger != null) {
    154                 final Parcel data = Parcel.obtain();
    155                 data.writeInterfaceToken("android.ui.ISurfaceComposer");
    156                 if (m != null) {
    157                     data.writeInt(1);
    158                     for (int i = 0; i < 16; i++) {
    159                         data.writeFloat(m[i]);
    160                     }
    161                 } else {
    162                     data.writeInt(0);
    163                 }
    164                 flinger.transact(1015, data, null, 0);
    165                 data.recycle();
    166             }
    167         } catch (RemoteException ex) {
    168             Slog.e(LOG_TAG, "Failed to set color transform", ex);
    169         }
    170     }
    171 
    172 }
    173