image_paint_timing_detector.h | Explore in Territory

// Copyright 2018 The Chromium Authors
// Use of this source code is governed by a BSD-style license that can be
// found in the LICENSE file.

// Copyright 2018 The Chromium Authors
// Use of this source code is governed by a BSD-style license that can be
// found in the LICENSE file.

#ifndef THIRD_PARTY_BLINK_RENDERER_CORE_PAINT_TIMING_IMAGE_PAINT_TIMING_DETECTOR_H_
#define THIRD_PARTY_BLINK_RENDERER_CORE_PAINT_TIMING_IMAGE_PAINT_TIMING_DETECTOR_H_

#include <optional>

#include "base/gtest_prod_util.h"
#include "base/time/time.h"
#include "third_party/blink/public/common/performance/largest_contentful_paint_type.h"
#include "third_party/blink/renderer/core/core_export.h"
#include "third_party/blink/renderer/core/dom/dom_node_ids.h"
#include "third_party/blink/renderer/core/loader/resource/image_resource_content.h"
#include "third_party/blink/renderer/core/paint/timing/lcp_objects.h"
#include "third_party/blink/renderer/core/paint/timing/media_record_id.h"
#include "third_party/blink/renderer/core/paint/timing/paint_timing_visualizer.h"
#include "third_party/blink/renderer/platform/allow_discouraged_type.h"
#include "third_party/blink/renderer/platform/heap/collection_support/heap_deque.h"
#include "third_party/blink/renderer/platform/heap/collection_support/heap_hash_set.h"
#include "third_party/blink/renderer/platform/heap/garbage_collected.h"
#include "third_party/blink/renderer/platform/loader/fetch/media_timing.h"
#include "third_party/blink/renderer/platform/wtf/cross_thread_functional.h"
#include "third_party/blink/renderer/platform/wtf/hash_set.h"
#include "ui/gfx/geometry/rect_conversions.h"

namespace blink {

class LayoutObject;
class LocalFrameView;
class PropertyTreeStateOrAlias;
class TracedValue;
class Image;
class PaintTimingCallbackManager;
class StyleImage;

// TODO(crbug/960502): we should limit the access of these properties.
// TODO(yoav): Rename all mentions of "image" to "media"
class ImageRecord : public GarbageCollected<ImageRecord> { … };

// |ImageRecordsManager| is the manager of all of the images that Largest
// Image Paint cares about. Note that an image does not necessarily correspond
// to a node; it can also be one of the background images attached to a node.
// |ImageRecordsManager| encapsulates the logic of |ImageRecord| handling,
// providing interface for the external world to handle it in the language of
// Node, LayoutObject, etc.
class CORE_EXPORT ImageRecordsManager { … };

// ImagePaintTimingDetector contains Largest Image Paint.
//
// Largest Image Paint timing measures when the largest image element within
// viewport finishes painting. Specifically, it:
// 1. Tracks all images' first invalidation, recording their visual size, if
// this image is within viewport.
// 2. When an image finishes loading, record its paint time.
// 3. At the end of each frame, if new images are added and loaded, the
// algorithm will start an analysis.
//
// In the analysis:
// 3.1 Largest Image Paint finds the largest image by the first visual size. If
// it has finished loading, reports a candidate result as its first paint time
// since loaded.
//
// For all these candidate results, Telemetry picks the lastly reported
// Largest Image Paint candidate as its final result.
//
// See also:
// https://docs.google.com/document/d/1DRVd4a2VU8-yyWftgOparZF-sf16daf0vfbsHuz2rws/edit#heading=h.1k2rnrs6mdmt
class CORE_EXPORT ImagePaintTimingDetector final
    : public GarbageCollected<ImagePaintTimingDetector> { … };
}  // namespace blink

#endif  // THIRD_PARTY_BLINK_RENDERER_CORE_PAINT_TIMING_IMAGE_PAINT_TIMING_DETECTOR_H_
chromium/third_party/blink/renderer/core/paint/timing/image_paint_timing_detector.h
