paulxstretch/deps/juce/modules/juce_events/timers/juce_Timer.h
essej 25bd5d8adb git subrepo clone --branch=sono6good https://github.com/essej/JUCE.git deps/juce
subrepo:
  subdir:   "deps/juce"
  merged:   "b13f9084e"
upstream:
  origin:   "https://github.com/essej/JUCE.git"
  branch:   "sono6good"
  commit:   "b13f9084e"
git-subrepo:
  version:  "0.4.3"
  origin:   "https://github.com/ingydotnet/git-subrepo.git"
  commit:   "2f68596"
2022-04-18 17:51:22 -04:00

138 lines
5.6 KiB
C++

/*
==============================================================================
This file is part of the JUCE library.
Copyright (c) 2020 - Raw Material Software Limited
JUCE is an open source library subject to commercial or open-source
licensing.
The code included in this file is provided under the terms of the ISC license
http://www.isc.org/downloads/software-support-policy/isc-license. Permission
To use, copy, modify, and/or distribute this software for any purpose with or
without fee is hereby granted provided that the above copyright notice and
this permission notice appear in all copies.
JUCE IS PROVIDED "AS IS" WITHOUT ANY WARRANTY, AND ALL WARRANTIES, WHETHER
EXPRESSED OR IMPLIED, INCLUDING MERCHANTABILITY AND FITNESS FOR PURPOSE, ARE
DISCLAIMED.
==============================================================================
*/
namespace juce
{
//==============================================================================
/**
Makes repeated callbacks to a virtual method at a specified time interval.
A Timer's timerCallback() method will be repeatedly called at a given
interval. When you create a Timer object, it will do nothing until the
startTimer() method is called, which will cause the message thread to
start making callbacks at the specified interval, until stopTimer() is called
or the object is deleted.
The time interval isn't guaranteed to be precise to any more than maybe
10-20ms, and the intervals may end up being much longer than requested if the
system is busy. Because the callbacks are made by the main message thread,
anything that blocks the message queue for a period of time will also prevent
any timers from running until it can carry on.
If you need to have a single callback that is shared by multiple timers with
different frequencies, then the MultiTimer class allows you to do that - its
structure is very similar to the Timer class, but contains multiple timers
internally, each one identified by an ID number.
@see HighResolutionTimer, MultiTimer
@tags{Events}
*/
class JUCE_API Timer
{
protected:
//==============================================================================
/** Creates a Timer.
When created, the timer is stopped, so use startTimer() to get it going.
*/
Timer() noexcept;
/** Creates a copy of another timer.
Note that this timer won't be started, even if the one you're copying
is running.
*/
Timer (const Timer&) noexcept;
public:
//==============================================================================
/** Destructor. */
virtual ~Timer();
//==============================================================================
/** The user-defined callback routine that actually gets called periodically.
It's perfectly ok to call startTimer() or stopTimer() from within this
callback to change the subsequent intervals.
*/
virtual void timerCallback() = 0;
//==============================================================================
/** Starts the timer and sets the length of interval required.
If the timer is already started, this will reset it, so the
time between calling this method and the next timer callback
will not be less than the interval length passed in.
@param intervalInMilliseconds the interval to use (any value less
than 1 will be rounded up to 1)
*/
void startTimer (int intervalInMilliseconds) noexcept;
/** Starts the timer with an interval specified in Hertz.
This is effectively the same as calling startTimer (1000 / timerFrequencyHz).
*/
void startTimerHz (int timerFrequencyHz) noexcept;
/** Stops the timer.
No more timer callbacks will be triggered after this method returns.
Note that if you call this from a background thread while the message-thread
is already in the middle of your callback, then this method will cancel any
future timer callbacks, but it will return without waiting for the current one
to finish. The current callback will continue, possibly still running some of
your timer code after this method has returned.
*/
void stopTimer() noexcept;
//==============================================================================
/** Returns true if the timer is currently running. */
bool isTimerRunning() const noexcept { return timerPeriodMs > 0; }
/** Returns the timer's interval.
@returns the timer's interval in milliseconds if it's running, or 0 if it's not.
*/
int getTimerInterval() const noexcept { return timerPeriodMs; }
//==============================================================================
/** Invokes a lambda after a given number of milliseconds. */
static void JUCE_CALLTYPE callAfterDelay (int milliseconds, std::function<void()> functionToCall);
//==============================================================================
/** For internal use only: invokes any timers that need callbacks.
Don't call this unless you really know what you're doing!
*/
static void JUCE_CALLTYPE callPendingTimersSynchronously();
private:
class TimerThread;
friend class TimerThread;
size_t positionInQueue = (size_t) -1;
int timerPeriodMs = 0;
Timer& operator= (const Timer&) = delete;
};
} // namespace juce