Cacheable WaitForSecondsUnscaled CustomYieldInstruction example

WaitForSecondsUnscaled.cs

/*
Copyright (c) 2016 Dmitriy Yukhanov
Permission is hereby granted, free of charge, to any person obtaining a copy of 
this software and associated documentation files (the "Software"), to deal in 
the Software without restriction, including without limitation the rights to 
use, copy, modify, merge, publish, distribute, sublicense, and/or sell copies 
of the Software, and to permit persons to whom the Software is furnished to do 
so, subject to the following conditions:
The above copyright notice and this permission notice shall be included in all 
copies or substantial portions of the Software.

THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR 
IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY, 
FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE 
AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER 
LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM, 
OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE SOFTWARE.
*/

using UnityEngine;

namespace CodeStage.Utils
{
	public class WaitForSecondsUnscaled : CustomYieldInstruction
	{
		private readonly float waitTime;
		private float runUntil;

		public override bool keepWaiting
		{
			get { return Time.unscaledTime < runUntil; }
		}

		/// <summary>
		/// Resets YieldInstruction for further re-use. Call it just before re-using.
		/// </summary>
		public new void Reset()
		{
			runUntil = Time.unscaledTime + waitTime;
		}

		/// <summary>
		/// Creates a yield instruction to wait for a given number of seconds using unscaled time.
		/// </summary>
		/// <param name="time">Time to wait before proceeding.</param>
		public WaitForSecondsUnscaled(float time)
		{
			waitTime = time;
		}
	}
}

/* Usage example:

	// declare a class field
	protected WaitForSecondsUnscaled cachedWaitForSecondsUnscaled;

	// use it in a coroutine
	// create cached instance when you'd like to, for example right at the coroutine
	if (cachedWaitForSecondsUnscaled == null)
		cachedWaitForSecondsUnscaled = new WaitForSecondsUnscaled(updateInterval);
      
	// reset before yielding
	cachedWaitForSecondsUnscaled.Reset();
  
	// yield as usual
	yield return cachedWaitForSecondsUnscaled;
*/