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      1 /*
      2  * Copyright (C) 2018 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.wm.utils;
     18 
     19 import android.graphics.Rect;
     20 import android.util.Size;
     21 import android.view.DisplayCutout;
     22 import android.view.Gravity;
     23 
     24 import java.util.List;
     25 import java.util.Objects;
     26 
     27 /**
     28  * Wrapper for DisplayCutout that also tracks the display size and using this allows (re)calculating
     29  * safe insets.
     30  */
     31 public class WmDisplayCutout {
     32 
     33     public static final WmDisplayCutout NO_CUTOUT = new WmDisplayCutout(DisplayCutout.NO_CUTOUT,
     34             null);
     35 
     36     private final DisplayCutout mInner;
     37     private final Size mFrameSize;
     38 
     39     public WmDisplayCutout(DisplayCutout inner, Size frameSize) {
     40         mInner = inner;
     41         mFrameSize = frameSize;
     42     }
     43 
     44     public static WmDisplayCutout computeSafeInsets(DisplayCutout inner,
     45             int displayWidth, int displayHeight) {
     46         if (inner == DisplayCutout.NO_CUTOUT || inner.isBoundsEmpty()) {
     47             return NO_CUTOUT;
     48         }
     49 
     50         final Size displaySize = new Size(displayWidth, displayHeight);
     51         final Rect safeInsets = computeSafeInsets(displaySize, inner);
     52         return new WmDisplayCutout(inner.replaceSafeInsets(safeInsets), displaySize);
     53     }
     54 
     55     /**
     56      * Insets the reference frame of the cutout in the given directions.
     57      *
     58      * @return a copy of this instance which has been inset
     59      * @hide
     60      */
     61     public WmDisplayCutout inset(int insetLeft, int insetTop, int insetRight, int insetBottom) {
     62         DisplayCutout newInner = mInner.inset(insetLeft, insetTop, insetRight, insetBottom);
     63 
     64         if (mInner == newInner) {
     65             return this;
     66         }
     67 
     68         Size frame = mFrameSize == null ? null : new Size(
     69                 mFrameSize.getWidth() - insetLeft - insetRight,
     70                 mFrameSize.getHeight() - insetTop - insetBottom);
     71 
     72         return new WmDisplayCutout(newInner, frame);
     73     }
     74 
     75     /**
     76      * Recalculates the cutout relative to the given reference frame.
     77      *
     78      * The safe insets must already have been computed, e.g. with {@link #computeSafeInsets}.
     79      *
     80      * @return a copy of this instance with the safe insets recalculated
     81      * @hide
     82      */
     83     public WmDisplayCutout calculateRelativeTo(Rect frame) {
     84         if (mInner.isEmpty()) {
     85             return this;
     86         }
     87         return inset(frame.left, frame.top,
     88                 mFrameSize.getWidth() - frame.right, mFrameSize.getHeight() - frame.bottom);
     89     }
     90 
     91     /**
     92      * Calculates the safe insets relative to the given display size.
     93      *
     94      * @return a copy of this instance with the safe insets calculated
     95      * @hide
     96      */
     97     public WmDisplayCutout computeSafeInsets(int width, int height) {
     98         return computeSafeInsets(mInner, width, height);
     99     }
    100 
    101     private static Rect computeSafeInsets(Size displaySize, DisplayCutout cutout) {
    102         if (displaySize.getWidth() < displaySize.getHeight()) {
    103             final List<Rect> boundingRects = cutout.replaceSafeInsets(
    104                     new Rect(0, displaySize.getHeight() / 2, 0, displaySize.getHeight() / 2))
    105                     .getBoundingRects();
    106             int topInset = findInsetForSide(displaySize, boundingRects, Gravity.TOP);
    107             int bottomInset = findInsetForSide(displaySize, boundingRects, Gravity.BOTTOM);
    108             return new Rect(0, topInset, 0, bottomInset);
    109         } else if (displaySize.getWidth() > displaySize.getHeight()) {
    110             final List<Rect> boundingRects = cutout.replaceSafeInsets(
    111                     new Rect(displaySize.getWidth() / 2, 0, displaySize.getWidth() / 2, 0))
    112                     .getBoundingRects();
    113             int leftInset = findInsetForSide(displaySize, boundingRects, Gravity.LEFT);
    114             int right = findInsetForSide(displaySize, boundingRects, Gravity.RIGHT);
    115             return new Rect(leftInset, 0, right, 0);
    116         } else {
    117             throw new UnsupportedOperationException("not implemented: display=" + displaySize +
    118                     " cutout=" + cutout);
    119         }
    120     }
    121 
    122     private static int findInsetForSide(Size display, List<Rect> boundingRects, int gravity) {
    123         int inset = 0;
    124         final int size = boundingRects.size();
    125         for (int i = 0; i < size; i++) {
    126             Rect boundingRect = boundingRects.get(i);
    127             switch (gravity) {
    128                 case Gravity.TOP:
    129                     if (boundingRect.top == 0) {
    130                         inset = Math.max(inset, boundingRect.bottom);
    131                     }
    132                     break;
    133                 case Gravity.BOTTOM:
    134                     if (boundingRect.bottom == display.getHeight()) {
    135                         inset = Math.max(inset, display.getHeight() - boundingRect.top);
    136                     }
    137                     break;
    138                 case Gravity.LEFT:
    139                     if (boundingRect.left == 0) {
    140                         inset = Math.max(inset, boundingRect.right);
    141                     }
    142                     break;
    143                 case Gravity.RIGHT:
    144                     if (boundingRect.right == display.getWidth()) {
    145                         inset = Math.max(inset, display.getWidth() - boundingRect.left);
    146                     }
    147                     break;
    148                 default:
    149                     throw new IllegalArgumentException("unknown gravity: " + gravity);
    150             }
    151         }
    152         return inset;
    153     }
    154 
    155     public DisplayCutout getDisplayCutout() {
    156         return mInner;
    157     }
    158 
    159     @Override
    160     public boolean equals(Object o) {
    161         if (!(o instanceof WmDisplayCutout)) {
    162             return false;
    163         }
    164         WmDisplayCutout that = (WmDisplayCutout) o;
    165         return Objects.equals(mInner, that.mInner) &&
    166                 Objects.equals(mFrameSize, that.mFrameSize);
    167     }
    168 
    169     @Override
    170     public int hashCode() {
    171         return Objects.hash(mInner, mFrameSize);
    172     }
    173 }
    174