| // Copyright 2018 The Chromium Authors. All rights reserved. |
| // 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_TIMING_LAYOUT_SHIFT_H_ |
| #define THIRD_PARTY_BLINK_RENDERER_CORE_TIMING_LAYOUT_SHIFT_H_ |
| |
| #include "third_party/blink/renderer/core/core_export.h" |
| #include "third_party/blink/renderer/core/dom/dom_high_res_time_stamp.h" |
| #include "third_party/blink/renderer/core/timing/layout_shift_attribution.h" |
| #include "third_party/blink/renderer/core/timing/performance_entry.h" |
| |
| namespace blink { |
| |
| // Exposes the layout shift score of an animation frame, computed as described |
| // in http://bit.ly/lsm-explainer. |
| class CORE_EXPORT LayoutShift final : public PerformanceEntry { |
| DEFINE_WRAPPERTYPEINFO(); |
| |
| public: |
| // Maximum number of attributions (shifted elements) to record in any single |
| // animation frame. |
| static constexpr int kMaxAttributions = 5; |
| typedef HeapVector<Member<LayoutShiftAttribution>, kMaxAttributions> |
| AttributionList; |
| |
| static LayoutShift* Create(double start_time, |
| double value, |
| bool input_detected, |
| double input_timestamp, |
| AttributionList sources); |
| |
| explicit LayoutShift(double start_time, |
| double value, |
| bool input_detected, |
| double input_timestamp, |
| AttributionList sources); |
| |
| ~LayoutShift() override; |
| |
| AtomicString entryType() const override; |
| PerformanceEntryType EntryTypeEnum() const override; |
| |
| double value() const { return value_; } |
| bool hadRecentInput() const { return had_recent_input_; } |
| double lastInputTime() const { return most_recent_input_timestamp_; } |
| |
| AttributionList sources() const { return sources_; } |
| |
| void Trace(Visitor*) override; |
| |
| private: |
| void BuildJSONValue(V8ObjectBuilder&) const override; |
| |
| double value_; |
| bool had_recent_input_; |
| DOMHighResTimeStamp most_recent_input_timestamp_; |
| AttributionList sources_; |
| }; |
| |
| } // namespace blink |
| |
| #endif // THIRD_PARTY_BLINK_RENDERER_CORE_TIMING_LAYOUT_SHIFT_H_ |