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Diffstat (limited to 'canvas/inc/canvas/elapsedtime.hxx')
-rw-r--r-- | canvas/inc/canvas/elapsedtime.hxx | 182 |
1 files changed, 182 insertions, 0 deletions
diff --git a/canvas/inc/canvas/elapsedtime.hxx b/canvas/inc/canvas/elapsedtime.hxx new file mode 100644 index 000000000000..c0ae5218eb64 --- /dev/null +++ b/canvas/inc/canvas/elapsedtime.hxx @@ -0,0 +1,182 @@ +/************************************************************************* + * + * DO NOT ALTER OR REMOVE COPYRIGHT NOTICES OR THIS FILE HEADER. + * + * Copyright 2000, 2010 Oracle and/or its affiliates. + * + * OpenOffice.org - a multi-platform office productivity suite + * + * This file is part of OpenOffice.org. + * + * OpenOffice.org is free software: you can redistribute it and/or modify + * it under the terms of the GNU Lesser General Public License version 3 + * only, as published by the Free Software Foundation. + * + * OpenOffice.org is distributed in the hope that it will be useful, + * but WITHOUT ANY WARRANTY; without even the implied warranty of + * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the + * GNU Lesser General Public License version 3 for more details + * (a copy is included in the LICENSE file that accompanied this code). + * + * You should have received a copy of the GNU Lesser General Public License + * version 3 along with OpenOffice.org. If not, see + * <http://www.openoffice.org/license.html> + * for a copy of the LGPLv3 License. + * + ************************************************************************/ + +#ifndef INCLUDED_CANVAS_ELAPSEDTIME_HXX +#define INCLUDED_CANVAS_ELAPSEDTIME_HXX + +#include <sal/types.h> + +#include "boost/shared_ptr.hpp" + +namespace canvas +{ + namespace tools + { + /** Calculate elapsed time. + + This class provides several time-measurement and + -management functions. In its simplest use-case, it + measures the time from its creation. + */ + class ElapsedTime + { + public: + /** Create a new ElapsedTime object + + The moment of construction starts the time + measurement. That means, a subsequent getElapsedTime() + call will return the time difference between object + creation and getElapsedTime() call. + */ + ElapsedTime(); + + /** Creates a new ElapsedTime object based on another + timer. + + The moment of construction starts the time + measurement. That means, a subsequent getElapsedTime() + call will return the time difference between object + creation and getElapsedTime() call. All time values + are not taken from the system's time base, but from + the provided timer. + */ + ElapsedTime( ::boost::shared_ptr<ElapsedTime> const & pTimeBase ); + + /** Gets this timer's base timer. + */ + ::boost::shared_ptr<ElapsedTime> const & getTimeBase() const; + + /** Reset the time + + The instance of the reset() call starts the time + measurement from scratch. That means, a subsequent + getElapsedTime() call will return the time difference + between reset() and getElapsedTime() call. + */ + void reset(); + + /** Query the elapsed time + + This method returns the elapsed time in seconds + between either the construction of this object, or the + last reset() call, if any (but see the time modulation + methods below, for means to modify the otherwise + continuous flow of time). + + @return the elapsed time in seconds. + */ + double getElapsedTime() const; + + /** Pauses the running timer. + + This method stops the time, as returned by this + object, until continueTimer() is called. During this + period, getElapsedTime() will always return the same + time value (i.e. the instant when pauseTimer() was + called). + */ + void pauseTimer(); + + /** Continues the paused timer. + + This method re-enables the time flow, that is, time + starts running again for clients calling + getElapsedTime(). The (subtle) difference to the + holdTimer/releaseTimer() methods below is, that there + is no perceived time 'jump' between the pauseTimer() + call and the continueTimer() call, i.e. the time + starts over with the same value it has stopped on + pauseTimer(). + */ + void continueTimer(); + + /** Adjusts the timer, hold and pause times. + + This method modifies the time as returned by this + object by the specified amount. This affects the time + as returned by getElapsedTime(), regardless of the + mode (e.g. paused, or on hold). + + @param fOffset + This value will be added to the current time, i.e. the + next call to getElapsedTime() (when performed + immediately) will be adjusted by fOffset. + + @param bLimitToLastQueriedTime + Limits the given offset to the time that has been + taken via getElapsedTime() + */ + void adjustTimer( double fOffset, + bool bLimitToLastQueriedTime = true ); + + /** Holds the current time. + + This call makes the timer hold the current time + (e.g. getElapsedTime() will return the time when + holdTimer() was called), while the underlying time is + running on. When releaseTimer() is called, the time + will 'jump' to the then-current, underlying time. This + is equivalent to pressing the "interim time" button on + a stop watch, which shows this stopped time, while the + clock keeps running internally. + */ + void holdTimer(); + + /** Releases a held timer. + + After this call, the timer again returns the running + time on getElapsedTime(). + */ + void releaseTimer(); + + private: + static double getSystemTime(); + double getCurrentTime() const; + double getElapsedTimeImpl() const; // does not set m_fLastQueriedTime + + const ::boost::shared_ptr<ElapsedTime> m_pTimeBase; + + /// To validate adjustTimer() calls with bLimitToLastQueriedTime=true + mutable double m_fLastQueriedTime; + + /// Start time, from which the difference to the time base is returned + double m_fStartTime; + + /// Instant, when last pause or hold started, relative to m_fStartTime + double m_fFrozenTime; + + /// True, when in pause mode + bool m_bInPauseMode; + + /// True, when in hold mode + bool m_bInHoldMode; + }; + + } +} + +#endif /* INCLUDED_CANVAS_ELAPSEDTIME_HXX */ |