| 12
 3
 4
 5
 6
 7
 8
 9
 10
 11
 12
 13
 14
 15
 16
 17
 18
 19
 20
 21
 22
 23
 24
 25
 26
 27
 28
 29
 30
 31
 32
 33
 34
 35
 36
 37
 38
 39
 40
 41
 42
 43
 44
 45
 46
 47
 48
 49
 50
 51
 52
 53
 54
 55
 56
 57
 58
 59
 60
 61
 62
 63
 64
 65
 66
 67
 68
 69
 70
 71
 72
 73
 74
 75
 76
 77
 78
 79
 80
 81
 82
 83
 84
 85
 86
 87
 88
 89
 90
 91
 92
 93
 94
 95
 96
 97
 98
 99
 100
 101
 102
 103
 104
 105
 106
 107
 108
 109
 110
 111
 112
 113
 114
 115
 116
 117
 118
 119
 120
 121
 122
 123
 124
 125
 126
 127
 128
 129
 130
 131
 132
 133
 134
 135
 136
 137
 138
 139
 
 | // Copyright 2020 The Chromium Authors
// Use of this source code is governed by a BSD-style license that can be
// found in the LICENSE file.
#include "chrome/browser/android/compose_bitmaps_helper.h"
#include "base/logging.h"
#include "third_party/skia/include/core/SkBitmap.h"
#include "third_party/skia/include/core/SkImageInfo.h"
#include "third_party/skia/include/core/SkPixmap.h"
namespace compose_bitmaps_helper {
// Ratio of icon size to the amount of padding between the icons.
const int kIconPaddingScale = 8;
std::unique_ptr<SkBitmap> ComposeBitmaps(const std::vector<SkBitmap>& bitmaps,
                                         int desired_size_in_pixel) {
  int num_icons = bitmaps.size();
  DVLOG(1) << "num icons: " << num_icons;
  if (num_icons == 0) {
    return nullptr;
  }
  DVLOG(1) << "desired_size_in_pixel: " << desired_size_in_pixel;
  int icon_padding_pixel_size = desired_size_in_pixel / kIconPaddingScale;
  // Offset to write icons out of frame due to padding.
  int icon_write_offset = icon_padding_pixel_size / 2;
  SkBitmap composite_bitmap;
  SkImageInfo image_info =
      bitmaps[0]
          .info()
          .makeWH(desired_size_in_pixel, desired_size_in_pixel)
          .makeAlphaType(kPremul_SkAlphaType);
  composite_bitmap.setInfo(image_info);
  composite_bitmap.allocPixels();
  int icon_size = desired_size_in_pixel / 2;
  // draw icons in correct areas
  switch (num_icons) {
    case 1: {
      // Centered.
      SkBitmap scaledBitmap = ScaleBitmap(icon_size, bitmaps[0]);
      if (scaledBitmap.empty()) {
        return nullptr;
      }
      composite_bitmap.writePixels(
          scaledBitmap.pixmap(),
          ((icon_size + icon_padding_pixel_size) / 2) - icon_write_offset,
          ((icon_size + icon_padding_pixel_size) / 2) - icon_write_offset);
      break;
    }
    case 2: {
      // Side by side.
      for (int i = 0; i < 2; i++) {
        SkBitmap scaledBitmap = ScaleBitmap(icon_size, bitmaps[i]);
        if (scaledBitmap.empty()) {
          return nullptr;
        }
        composite_bitmap.writePixels(
            scaledBitmap.pixmap(),
            (i * (icon_size + icon_padding_pixel_size)) - icon_write_offset,
            ((icon_size + icon_padding_pixel_size) / 2) - icon_write_offset);
      }
      break;
    }
    case 3: {
      // Two on top, one on bottom.
      for (int i = 0; i < 3; i++) {
        SkBitmap scaledBitmap = ScaleBitmap(icon_size, bitmaps[i]);
        if (scaledBitmap.empty()) {
          return nullptr;
        }
        switch (i) {
          case 0:
            composite_bitmap.writePixels(
                scaledBitmap.pixmap(), -icon_write_offset, -icon_write_offset);
            break;
          case 1:
            composite_bitmap.writePixels(
                scaledBitmap.pixmap(),
                (icon_size + icon_padding_pixel_size) - icon_write_offset,
                -icon_write_offset);
            break;
          default:
            composite_bitmap.writePixels(
                scaledBitmap.pixmap(),
                ((icon_size + icon_padding_pixel_size) / 2) - icon_write_offset,
                (icon_size + icon_padding_pixel_size) - icon_write_offset);
            break;
        }
      }
      break;
    }
    case 4: {
      // One in each corner.
      for (int i = 0; i < 2; i++) {
        for (int j = 0; j < 2; j++) {
          int index = i + 2 * j;
          SkBitmap scaledBitmap = ScaleBitmap(icon_size, bitmaps[index]);
          if (scaledBitmap.empty()) {
            return nullptr;
          }
          composite_bitmap.writePixels(
              scaledBitmap.pixmap(),
              (j * (icon_size + icon_padding_pixel_size)) - icon_write_offset,
              (i * (icon_size + icon_padding_pixel_size)) - icon_write_offset);
        }
      }
      break;
    }
    default:
      DLOG(ERROR) << "Invalid number of icons to combine: " << bitmaps.size();
      return nullptr;
  }
  return std::make_unique<SkBitmap>(composite_bitmap);
}
SkBitmap ScaleBitmap(int icon_size, const SkBitmap& bitmap) {
  SkBitmap temp_bitmap;
  SkImageInfo scaledIconInfo = bitmap.info().makeWH(icon_size, icon_size);
  temp_bitmap.setInfo(scaledIconInfo);
  temp_bitmap.allocPixels();
  const SkSamplingOptions mitchellCubic({1.0f/3, 1.0f/3});
  bool did_scale =
      bitmap.pixmap().scalePixels(temp_bitmap.pixmap(), mitchellCubic);
  if (!did_scale) {
    DLOG(ERROR) << "Unable to scale icon";
    return SkBitmap();
  }
  return temp_bitmap;
}
}  // namespace compose_bitmaps_helper
 |