TimeModule

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Scripting API

TimeModule

The TimeModule class enables time-based events.

Example

//===========================================================================
// The following example demonstrates how to call a function repeatedly every
// 0.5 seconds as well as call a function once after 5 seconds has passed.
//
// Project setup:
// - Insert a plane
// - Insert a cube 3D primitive from the Asset Library
//===========================================================================


// Load the required modules
const Scene = require('Scene');
const Time = require('Time');
const Reactive = require('Reactive');


(async function() { // Enable async/await in JS [part 1]

  // Locate the plane in the Scene
  const [plane] = await Promise.all([
    Scene.root.findFirst('plane0')
  ]);

  // Create a variable used in the timers
  const timeInMilliseconds = 500;


  //==========================================================================
  // Increase and decrease the scale of the plane every 0.5 seconds
  //==========================================================================

  // Create a boolean to determine if the plane's width is doubled or not
  var isPlaneDoubleWidth = false;

  // Store a reference to the plane's transform signal
  const planeTransform = plane.transform;

  // Store a reference to the plane's initial x-axis scale value
  const planeWidth = planeTransform.scaleX.pinLastValue();

  // Create a function that changes the width of the plane
  function changePlaneWidth() {
    // If the plane's width is not doubled...
    if (!isPlaneDoubleWidth) {
      // Multiply the x-axis scale value of the plane by 2, doubling it
      planeTransform.scaleX = Reactive.mul(planeWidth, 2);

    // Otherwise...
    } else {
      // Set the x-axis scale back to it's original value, halving it
      planeTransform.scaleX = planeWidth;
    }
    // Update the boolean
    isPlaneDoubleWidth = !isPlaneDoubleWidth;
  }

  // Create an interval timer that calls the changePlaneWidth function every 0.5
  // seconds
  const intervalTimer = Time.setInterval(changePlaneWidth, timeInMilliseconds);


  //==========================================================================
  // Stop the interval timer after 5 seconds using a timeout timer
  //==========================================================================

  // Create a function that stops the interval timer
  function stopIntervalTimer() {
    Time.clearInterval(intervalTimer);
  }

  // Create a timeout timer that calls the stopIntervalTimer function after 5
  // seconds have passed
  const timeoutTimer = Time.setTimeout(stopIntervalTimer, timeInMilliseconds * 10);


  //==========================================================================
  // Animate an object along its forward vector with delta time
  //==========================================================================
  
  // Locate the cube object in the scene
  const cube = await Scene.root.findFirst('Cube');

  // Create a new vector
  const vector = Reactive.vector(0, 0, -1);
  
  // Rotate the cube by the cube's rotation vector
  const rotatedVector = vector.rotate(cube.transform.rotation);

  // Set the velocity using delta time
  const velocity = Time.deltaTimeMS.div(1000).mul(rotatedVector);
 
  // Animate the cube along its forward vector at the velocity specified
  cube.transform.position = cube.transform.position.history(1).frame(-1).add(velocity);

})(); // Enable async/await in JS [part 2]

Properties

Property	Description
`deltaTimeMS`	(get) deltaTimeMS: ScalarSignal (set) (Not Available) Retrieves delta time information in milliseconds from the effect. You can use the delta time value to create animations which transition independently of the frame rate. See the main example on the page.
`ms`	(get) ms: ScalarSignal (set) (Not Available) Specifies a `ScalarSignal` indicating the number of milliseconds elapsed since the first frame.

Methods

Method	Description
`clearInterval`	clearInterval(subscription: Subscription): void Cancels a callback set by `setInterval`. This function is provided as a to match the traditional JS `clearInterval` API. Note: This is equivalent to `Subscription.unsubscribe`.
`clearTimeout`	clearTimeout(subscription: Subscription): void Cancels a callback set by `setTimeout`. This has no effect if the timeout has already been triggered. This function is provided as a to match the traditional JS `clearTimeout` API. Note: This is equivalent to `Subscription.unsubscribe`.
`setInterval`	setInterval(callback: {}, delay: number): Subscription Returns a `Subscription` object. The function specified by `callback` is called at intervals specified by `delay` in milliseconds. The `setInterval` will continue calling the `callback` until `TimeModule.clearInterval` is called. The `callback` is a function that has one argument, the elapsed time since the timer started. An exception is thrown when the `delay` is zero or less. Note: An interval can be canceled either via `Subscription.unsubscribe` or `TimeModule.clearInterval`.
`setIntervalWithSnapshot`	setIntervalWithSnapshot(snapshot: {[name: string]: BoolSignal \| ScalarSignal \| StringSignal}, callback: {}, delay: number): Subscription Returns a `Subscription` object. The function specified by `callback` is called at intervals specified by `delay` in milliseconds using `Snapshot` of signals. `Snapshot` is a dictionary of String/Bool/Scalar signals, which will be passed as JSON to the callback function using lastValue from requested signals. The `setIntervalWithSnapshot` will continue calling the `callback` until `TimeModule.clearInterval` is called. The `callback` is a function that has two arguments, the elapsed time since the timer started, and the snapshot JSON An exception is thrown when the `delay` is zero or less. Note: An interval can be canceled either via `Subscription.unsubscribe` or `TimeModule.clearInterval`.
`setTimeout`	setTimeout(callback: {}, delay: number): Subscription Returns a `Subscription` object. The function specified by `callback` is called after the specified `delay` in milliseconds. The `callback` is a function that has one argument, the elapsed time since the timer started. Note: A timeout can be canceled either via `Subscription.unsubscribe` or `TimeModule.clearTimeout`. Note: This is equivalent to `Time.ms.sub(Time.ms.pin()).trigger(delay).subscribe(callback)`.
`setTimeoutWithSnapshot`	setTimeoutWithSnapshot(snapshot: {[name: string]: BoolSignal \| ScalarSignal \| StringSignal}, callback: {}, delay: number): Subscription Returns a `Subscription` object. The function specified by `callback` is called after the specified `delay` in milliseconds using `Snapshot` of signals. `Snapshot` is a dictionary of String/Bool/Scalar signals, which will be passed as JSON to the callback function using lastValue from requested signals. The `callback` is a function that has two arguments, the elapsed time since the timer started and the snapshot JSON. Note: A timeout can be canceled either via `Subscription.unsubscribe` or `TimeModule.clearTimeout`. Note: This is equivalent to `Time.ms.sub(Time.ms.pin()).trigger(delay).subscribeWithSnapshot(snapshot, callback)`.

Classes

This module exposes no classes.

TimeModule

Contents

Contents

Example

Properties

Methods

Classes