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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     /** Matrix and offset used for value-only display inversion. */
     45     private static final float[] INVERSION_MATRIX_VALUE_ONLY = new float[] {
     46            0, -.5f, -.5f, 0,
     47         -.5f,    0, -.5f, 0,
     48         -.5f, -.5f,    0, 0,
     49            1,    1,    1, 1
     50     };
     51 
     52     /** Default inversion mode for display color correction. */
     53     private static final int DEFAULT_DISPLAY_DALTONIZER =
     54             AccessibilityManager.DALTONIZER_CORRECT_DEUTERANOMALY;
     55 
     56     /**
     57      * Returns whether the specified user with has any display color
     58      * adjustments.
     59      */
     60     public static boolean hasAdjustments(Context context, int userId) {
     61         final ContentResolver cr = context.getContentResolver();
     62 
     63         if (Settings.Secure.getIntForUser(cr,
     64                 Settings.Secure.ACCESSIBILITY_DISPLAY_INVERSION_ENABLED, 0, userId) != 0) {
     65             return true;
     66         }
     67 
     68         if (Settings.Secure.getIntForUser(cr,
     69                 Settings.Secure.ACCESSIBILITY_DISPLAY_DALTONIZER_ENABLED, 0, userId) != 0) {
     70             return true;
     71         }
     72 
     73         return false;
     74     }
     75 
     76     /**
     77      * Applies the specified user's display color adjustments.
     78      */
     79     public static void applyAdjustments(Context context, int userId) {
     80         final ContentResolver cr = context.getContentResolver();
     81         float[] colorMatrix = null;
     82 
     83         if (Settings.Secure.getIntForUser(cr,
     84                 Settings.Secure.ACCESSIBILITY_DISPLAY_INVERSION_ENABLED, 0, userId) != 0) {
     85             colorMatrix = multiply(colorMatrix, INVERSION_MATRIX_VALUE_ONLY);
     86         }
     87 
     88         if (Settings.Secure.getIntForUser(cr,
     89                 Settings.Secure.ACCESSIBILITY_DISPLAY_DALTONIZER_ENABLED, 0, userId) != 0) {
     90             final int daltonizerMode = Settings.Secure.getIntForUser(cr,
     91                     Settings.Secure.ACCESSIBILITY_DISPLAY_DALTONIZER, DEFAULT_DISPLAY_DALTONIZER,
     92                     userId);
     93             // Monochromacy isn't supported by the native Daltonizer.
     94             if (daltonizerMode == AccessibilityManager.DALTONIZER_SIMULATE_MONOCHROMACY) {
     95                 colorMatrix = multiply(colorMatrix, GRAYSCALE_MATRIX);
     96                 setDaltonizerMode(AccessibilityManager.DALTONIZER_DISABLED);
     97             } else {
     98                 setDaltonizerMode(daltonizerMode);
     99             }
    100         } else {
    101             setDaltonizerMode(AccessibilityManager.DALTONIZER_DISABLED);
    102         }
    103 
    104         setColorTransform(colorMatrix);
    105     }
    106 
    107     private static float[] multiply(float[] matrix, float[] other) {
    108         if (matrix == null) {
    109             return other;
    110         }
    111         float[] result = new float[16];
    112         Matrix.multiplyMM(result, 0, matrix, 0, other, 0);
    113         return result;
    114     }
    115 
    116     /**
    117      * Sets the surface flinger's Daltonization mode. This adjusts the color
    118      * space to correct for or simulate various types of color blindness.
    119      *
    120      * @param mode new Daltonization mode
    121      */
    122     private static void setDaltonizerMode(int mode) {
    123         try {
    124             final IBinder flinger = ServiceManager.getService("SurfaceFlinger");
    125             if (flinger != null) {
    126                 final Parcel data = Parcel.obtain();
    127                 data.writeInterfaceToken("android.ui.ISurfaceComposer");
    128                 data.writeInt(mode);
    129                 flinger.transact(1014, data, null, 0);
    130                 data.recycle();
    131             }
    132         } catch (RemoteException ex) {
    133             Slog.e(LOG_TAG, "Failed to set Daltonizer mode", ex);
    134         }
    135     }
    136 
    137     /**
    138      * Sets the surface flinger's color transformation as a 4x4 matrix. If the
    139      * matrix is null, color transformations are disabled.
    140      *
    141      * @param m the float array that holds the transformation matrix, or null to
    142      *            disable transformation
    143      */
    144     private static void setColorTransform(float[] m) {
    145         try {
    146             final IBinder flinger = ServiceManager.getService("SurfaceFlinger");
    147             if (flinger != null) {
    148                 final Parcel data = Parcel.obtain();
    149                 data.writeInterfaceToken("android.ui.ISurfaceComposer");
    150                 if (m != null) {
    151                     data.writeInt(1);
    152                     for (int i = 0; i < 16; i++) {
    153                         data.writeFloat(m[i]);
    154                     }
    155                 } else {
    156                     data.writeInt(0);
    157                 }
    158                 flinger.transact(1015, data, null, 0);
    159                 data.recycle();
    160             }
    161         } catch (RemoteException ex) {
    162             Slog.e(LOG_TAG, "Failed to set color transform", ex);
    163         }
    164     }
    165 
    166 }
    167