1 // Copyright 2015 The Chromium Authors
2 // Use of this source code is governed by a BSD-style license that can be
3 // found in the LICENSE file.
5 #ifndef CC_TILES_IMAGE_DECODE_CACHE_H_
6 #define CC_TILES_IMAGE_DECODE_CACHE_H_
8 #include "base/memory/ref_counted.h"
9 #include "base/notreached.h"
10 #include "cc/base/devtools_instrumentation.h"
11 #include "cc/cc_export.h"
12 #include "cc/paint/decoded_draw_image.h"
13 #include "cc/paint/draw_image.h"
14 #include "cc/raster/tile_task.h"
15 #include "cc/tiles/image_decode_cache_utils.h"
16 #include "cc/tiles/tile_priority.h"
20 // ImageDecodeCache is responsible for generating decode tasks, decoding
21 // images, storing images in cache, and being able to return the decoded images
24 // ImageDecodeCache is responsible for the following things:
25 // 1. Given a DrawImage, it can return an TileTask which when run will
26 // decode and cache the resulting image. If the image does not need a task to
27 // be decoded, then nullptr will be returned. The return value of the
28 // function indicates whether the image was or is going to be locked, so an
29 // unlock will be required.
30 // 2. Given a cache key and a DrawImage, it can decode the image and store it in
31 // the cache. Note that it is important that this function is only accessed
32 // via an image decode task.
33 // 3. Given a DrawImage, it can return a DecodedDrawImage, which represented the
34 // decoded version of the image. Note that if the image is not in the cache
35 // and it needs to be scaled/decoded, then this decode will happen as part of
36 // getting the image. As such, this should only be accessed from a raster
38 class CC_EXPORT ImageDecodeCache {
40 enum class TaskType { kInRaster, kOutOfRaster };
42 // This information should be used strictly in tracing, UMA, and any other
45 TracingInfo(uint64_t prepare_tiles_id,
46 TilePriority::PriorityBin requesting_tile_bin,
48 : prepare_tiles_id(prepare_tiles_id),
49 requesting_tile_bin(requesting_tile_bin),
50 task_type(task_type) {}
51 TracingInfo() = default;
53 // ID for the current prepare tiles call.
54 const uint64_t prepare_tiles_id = 0;
56 // The bin of the tile that caused this image to be requested.
57 const TilePriority::PriorityBin requesting_tile_bin = TilePriority::NOW;
59 // Whether the decode is requested as a part of tile rasterization.
60 const TaskType task_type = TaskType::kInRaster;
63 static devtools_instrumentation::ScopedImageDecodeTask::TaskType
64 ToScopedTaskType(TaskType task_type) {
65 using ScopedTaskType =
66 devtools_instrumentation::ScopedImageDecodeTask::TaskType;
68 case TaskType::kInRaster:
69 return ScopedTaskType::kInRaster;
70 case TaskType::kOutOfRaster:
71 return ScopedTaskType::kOutOfRaster;
74 return ScopedTaskType::kInRaster;
77 static devtools_instrumentation::ScopedImageDecodeTask::ImageType
78 ToScopedImageType(ImageType image_type) {
79 using ScopedImageType =
80 devtools_instrumentation::ScopedImageDecodeTask::ImageType;
83 return ScopedImageType::kJxl;
84 case ImageType::kAVIF:
85 return ScopedImageType::kAvif;
87 return ScopedImageType::kBmp;
89 return ScopedImageType::kGif;
91 return ScopedImageType::kIco;
92 case ImageType::kJPEG:
93 return ScopedImageType::kJpeg;
95 return ScopedImageType::kPng;
96 case ImageType::kWEBP:
97 return ScopedImageType::kWebP;
98 case ImageType::kInvalid:
99 return ScopedImageType::kOther;
103 virtual ~ImageDecodeCache() {}
105 struct CC_EXPORT TaskResult {
106 explicit TaskResult(bool need_unref,
107 bool is_at_raster_decode,
108 bool can_do_hardware_accelerated_decode);
109 explicit TaskResult(scoped_refptr<TileTask> task,
110 bool can_do_hardware_accelerated_decode);
111 TaskResult(const TaskResult& result);
114 scoped_refptr<TileTask> task;
115 bool need_unref = false;
116 bool is_at_raster_decode = false;
117 bool can_do_hardware_accelerated_decode = false;
119 // Fill in an TileTask which will decode the given image when run. In
120 // case the image is already cached, fills in nullptr. Returns true if the
121 // image needs to be unreffed when the caller is finished with it.
123 // This is called by the tile manager (on the compositor thread) when creating
125 virtual TaskResult GetTaskForImageAndRef(const DrawImage& image,
126 const TracingInfo& tracing_info) = 0;
127 // Similar to GetTaskForImageAndRef, except that it returns tasks that are not
128 // meant to be run as part of raster. That is, this is part of a predecode
129 // API. Note that this should only return a task responsible for decoding (and
130 // not uploading), since it will be run on a worker thread which may not have
131 // the right GPU context for upload.
132 virtual TaskResult GetOutOfRasterDecodeTaskForImageAndRef(
133 const DrawImage& image) = 0;
135 // Unrefs an image. When the tile is finished, this should be called for every
136 // GetTaskForImageAndRef call that returned true.
137 virtual void UnrefImage(const DrawImage& image) = 0;
139 // Returns a decoded draw image. This may cause a decode if the image was not
142 // This is called by a raster task (on a worker thread) when an image is
145 // TODO(khushalsagar/vmpstr): Since the cache knows if it's a video frame, it
146 // should discard any frames from the same source not in use in the
148 virtual DecodedDrawImage GetDecodedImageForDraw(const DrawImage& image) = 0;
149 // Unrefs an image. This should be called for every GetDecodedImageForDraw
150 // when the draw with the image is finished.
151 virtual void DrawWithImageFinished(const DrawImage& image,
152 const DecodedDrawImage& decoded_image) = 0;
154 // This function informs the cache that now is a good time to clean up
155 // memory. This is called periodically from the compositor thread.
156 virtual void ReduceCacheUsage() = 0;
158 // This function informs the cache that we are hidden and should not be
159 // retaining cached resources longer than needed.
160 virtual void SetShouldAggressivelyFreeResources(
161 bool aggressively_free_resources) = 0;
163 // Clears all elements from the cache.
164 virtual void ClearCache() = 0;
166 // Returns the maximum amount of memory we would be able to lock. This ignores
167 // any temporary states, such as throttled, and return the maximum possible
168 // memory. It is used as an esimate of whether an image can fit into the
169 // locked budget before creating a task.
170 virtual size_t GetMaximumMemoryLimitBytes() const = 0;
172 // Returns true if the cache should be used for |image|. In certain cases the
173 // image can directly be used for raster (for instance bitmaps in a software
175 virtual bool UseCacheForDrawImage(const DrawImage& image) const = 0;
177 // Should be called periodically to record statistics about cache use and
179 virtual void RecordStats() = 0;
184 #endif // CC_TILES_IMAGE_DECODE_CACHE_H_