PotentialCheckerboardDurationTracker.h (2100B)
1 /* -*- Mode: C++; tab-width: 8; indent-tabs-mode: nil; c-basic-offset: 2 -*- */ 2 /* vim: set ts=8 sts=2 et sw=2 tw=80: */ 3 /* This Source Code Form is subject to the terms of the Mozilla Public 4 * License, v. 2.0. If a copy of the MPL was not distributed with this 5 * file, You can obtain one at http://mozilla.org/MPL/2.0/. */ 6 7 #ifndef mozilla_layers_PotentialCheckerboardDurationTracker_h 8 #define mozilla_layers_PotentialCheckerboardDurationTracker_h 9 10 #include "mozilla/TimeStamp.h" 11 12 namespace mozilla { 13 namespace layers { 14 15 /** 16 * This class allows the owner to track the duration of time considered 17 * "potentially checkerboarding". This is the union of two possibly-intersecting 18 * sets of time periods. The first set is that in which checkerboarding was 19 * actually happening, since by definition it could potentially be happening. 20 * The second set is that in which the APZC is actively transforming content 21 * in the compositor, since it could potentially transform it so as to display 22 * checkerboarding to the user. 23 * The caller of this class calls the appropriate methods to indicate the start 24 * and stop of these two sets, and this class manages accumulating the union 25 * of the various durations. 26 */ 27 class PotentialCheckerboardDurationTracker { 28 public: 29 PotentialCheckerboardDurationTracker(); 30 31 /** 32 * This should be called if checkerboarding is encountered. It can be called 33 * multiple times during a checkerboard event. 34 */ 35 void CheckerboardSeen(); 36 /** 37 * This should be called when checkerboarding is done. It must have been 38 * preceded by one or more calls to CheckerboardSeen(). 39 */ 40 void CheckerboardDone(bool aRecordTelemetry); 41 42 /** 43 * This should be called at composition time, to indicate if the APZC is in 44 * a transforming state or not. 45 */ 46 void InTransform(bool aInTransform, bool aRecordTelemetry); 47 48 private: 49 bool Tracking() const; 50 51 private: 52 bool mInCheckerboard; 53 bool mInTransform; 54 55 TimeStamp mCurrentPeriodStart; 56 }; 57 58 } // namespace layers 59 } // namespace mozilla 60 61 #endif // mozilla_layers_PotentialCheckerboardDurationTracker_h