terminal/src/cascadia/TerminalControl/ThrottledFunc.cpp
greg904 58f5d7c72e
Update _TerminalCursorPositionChanged to use ThrottledFunc (#6492)
* Update _TerminalCursorPositionChanged to use ThrottledFunc.
* Rename previous ThrottledFunc to ThrottledArgFunc because now
  ThrottledFunc is for functions that do not take an argument.
* Update ThrottledFunc and ThrottledArgFunc to accept a CoreDispatcher
  on which the function should be called for convenience.
* Don't use coroutines/winrt::fire_and_forget in
  ThrottledFunc/ThrottledArgFunc because they are too slow (see PR).

_AdjustCursorPosition went from 17% of samples to 3% in performance
testing.
2020-06-23 14:05:40 -07:00

55 lines
1.5 KiB
C++

// Copyright (c) Microsoft Corporation.
// Licensed under the MIT license.
#include "pch.h"
#include "ThrottledFunc.h"
using namespace winrt::Windows::Foundation;
using namespace winrt::Windows::UI::Core;
using namespace winrt::Windows::UI::Xaml;
ThrottledFunc<>::ThrottledFunc(ThrottledFunc::Func func, TimeSpan delay, CoreDispatcher dispatcher) :
_func{ func },
_delay{ delay },
_dispatcher{ dispatcher },
_isRunPending{}
{
}
// Method Description:
// - Runs the function later, except if `Run` is called again before
// with a new argument, in which case the request will be ignored.
// - For more information, read the class' documentation.
// - This method is always thread-safe. It can be called multiple times on
// different threads.
// Arguments:
// - <none>
// Return Value:
// - <none>
void ThrottledFunc<>::Run()
{
if (_isRunPending.test_and_set())
{
// already pending
return;
}
_dispatcher.RunAsync(CoreDispatcherPriority::Low, [weakThis = this->weak_from_this()]() {
if (auto self{ weakThis.lock() })
{
DispatcherTimer timer;
timer.Interval(self->_delay);
timer.Tick([=](auto&&...) {
if (auto self{ weakThis.lock() })
{
timer.Stop();
self->_isRunPending.clear();
self->_func();
}
});
timer.Start();
}
});
}