1 // Copyright (c) 2013 The Chromium Authors. All rights reserved.
2 // Use of this source code is governed by a BSD-style license that can be
3 // found in the LICENSE file.
5 #include "ash/desktop_background/wallpaper_resizer.h"
7 #include "ash/desktop_background/wallpaper_resizer_observer.h"
9 #include "base/logging.h"
10 #include "base/threading/sequenced_worker_pool.h"
11 #include "base/threading/worker_pool.h"
12 #include "content/public/browser/browser_thread.h"
13 #include "third_party/skia/include/core/SkImage.h"
14 #include "ui/base/resource/resource_bundle.h"
15 #include "ui/gfx/image/image_skia_rep.h"
16 #include "ui/gfx/skia_util.h"
18 using content::BrowserThread;
23 // For our scaling ratios we need to round positive numbers.
24 int RoundPositive(double x) {
25 return static_cast<int>(floor(x + 0.5));
28 // Resizes |orig_bitmap| to |target_size| using |layout| and stores the
29 // resulting bitmap at |resized_bitmap_out|.
30 void Resize(SkBitmap orig_bitmap,
31 const gfx::Size& target_size,
32 WallpaperLayout layout,
33 SkBitmap* resized_bitmap_out) {
34 DCHECK(BrowserThread::GetBlockingPool()->RunsTasksOnCurrentThread());
35 SkBitmap new_bitmap = orig_bitmap;
37 const int orig_width = orig_bitmap.width();
38 const int orig_height = orig_bitmap.height();
39 const int new_width = target_size.width();
40 const int new_height = target_size.height();
42 if (orig_width > new_width || orig_height > new_height) {
43 gfx::Rect wallpaper_rect(0, 0, orig_width, orig_height);
44 gfx::Size cropped_size = gfx::Size(std::min(new_width, orig_width),
45 std::min(new_height, orig_height));
47 case WALLPAPER_LAYOUT_CENTER:
48 wallpaper_rect.ClampToCenteredSize(cropped_size);
49 orig_bitmap.extractSubset(&new_bitmap,
50 gfx::RectToSkIRect(wallpaper_rect));
52 case WALLPAPER_LAYOUT_TILE:
53 wallpaper_rect.set_size(cropped_size);
54 orig_bitmap.extractSubset(&new_bitmap,
55 gfx::RectToSkIRect(wallpaper_rect));
57 case WALLPAPER_LAYOUT_STRETCH:
58 new_bitmap = skia::ImageOperations::Resize(
59 orig_bitmap, skia::ImageOperations::RESIZE_LANCZOS3,
60 new_width, new_height);
62 case WALLPAPER_LAYOUT_CENTER_CROPPED:
63 if (orig_width > new_width && orig_height > new_height) {
64 // The dimension with the smallest ratio must be cropped, the other
65 // one is preserved. Both are set in gfx::Size cropped_size.
66 double horizontal_ratio = static_cast<double>(new_width) /
67 static_cast<double>(orig_width);
68 double vertical_ratio = static_cast<double>(new_height) /
69 static_cast<double>(orig_height);
71 if (vertical_ratio > horizontal_ratio) {
72 cropped_size = gfx::Size(
73 RoundPositive(static_cast<double>(new_width) / vertical_ratio),
76 cropped_size = gfx::Size(orig_width, RoundPositive(
77 static_cast<double>(new_height) / horizontal_ratio));
79 wallpaper_rect.ClampToCenteredSize(cropped_size);
81 orig_bitmap.extractSubset(&sub_image,
82 gfx::RectToSkIRect(wallpaper_rect));
83 new_bitmap = skia::ImageOperations::Resize(
84 sub_image, skia::ImageOperations::RESIZE_LANCZOS3,
85 new_width, new_height);
90 *resized_bitmap_out = new_bitmap;
91 resized_bitmap_out->setImmutable();
97 uint32_t WallpaperResizer::GetImageId(const gfx::ImageSkia& image) {
98 const gfx::ImageSkiaRep& image_rep = image.GetRepresentation(1.0f);
99 return image_rep.is_null() ? 0 : image_rep.sk_bitmap().getGenerationID();
102 WallpaperResizer::WallpaperResizer(int image_resource_id,
103 const gfx::Size& target_size,
104 WallpaperLayout layout)
105 : image_(*(ui::ResourceBundle::GetSharedInstance()
106 .GetImageNamed(image_resource_id)
108 original_image_id_(GetImageId(image_)),
109 resource_id_(image_resource_id),
110 target_size_(target_size),
112 weak_ptr_factory_(this) {
113 image_.MakeThreadSafe();
116 WallpaperResizer::WallpaperResizer(const gfx::ImageSkia& image,
117 const gfx::Size& target_size,
118 WallpaperLayout layout)
120 original_image_id_(GetImageId(image_)),
121 resource_id_(DesktopBackgroundController::kInvalidResourceID),
122 target_size_(target_size),
124 weak_ptr_factory_(this) {
125 image_.MakeThreadSafe();
128 WallpaperResizer::~WallpaperResizer() {
131 void WallpaperResizer::StartResize() {
132 DCHECK(BrowserThread::CurrentlyOn(BrowserThread::UI));
133 SkBitmap* resized_bitmap = new SkBitmap;
134 if (!content::BrowserThread::PostBlockingPoolTaskAndReply(
136 base::Bind(&Resize, *image_.bitmap(), target_size_,
137 layout_, resized_bitmap),
138 base::Bind(&WallpaperResizer::OnResizeFinished,
139 weak_ptr_factory_.GetWeakPtr(),
140 base::Owned(resized_bitmap)))) {
141 LOG(WARNING) << "PostSequencedWorkerTask failed. "
142 << "Wallpaper may not be resized.";
146 void WallpaperResizer::AddObserver(WallpaperResizerObserver* observer) {
147 observers_.AddObserver(observer);
150 void WallpaperResizer::RemoveObserver(WallpaperResizerObserver* observer) {
151 observers_.RemoveObserver(observer);
154 void WallpaperResizer::OnResizeFinished(SkBitmap* resized_bitmap) {
155 DCHECK(BrowserThread::CurrentlyOn(BrowserThread::UI));
156 image_ = gfx::ImageSkia::CreateFrom1xBitmap(*resized_bitmap);
157 FOR_EACH_OBSERVER(WallpaperResizerObserver, observers_,
158 OnWallpaperResized());