FrameAPI

Interface FrameAPI

FrameAPI

Overview

The FrameAPI provides functions for registering and unregistering frame listeners which are executed on every tick of the internal update loop of the webvis context.

The FrameAPI might be used to:

  • process events that have been collected between frames in a batched manner
  • perform complex animations that cannot be implemented using the AnimationAPI
  • record properties of the scene, like the camera position and orientation

Quick Start

To get started with the FrameAPI, you can register a listener via the webvis context:

const context = webvis.getContext();

// Define your frame listener
const myFrameListener = (time, elapsed) =>
{
    console.log(`Time of current tick: ${time} ms. Time since last tick: ${elapsed} ms.`);
};

// Register your frame listener
context.registerFrameListener(myFrameListener);

// Later unregister your frame listener
context.unregisterFrameListener(myFrameListener);

Execution Behavior

The execution frequency of a frame listener will usually match the refresh rate of the display, which is typically around 60 Hz. Frame listener execution might be throttled when the document is not visible (e.g., when the browser tab is in the background).

When executed, a listener receives the timestamp of the current tick of the internal update loop and the elapsed time since the last tick. Custom logic should never assume a specific update rate, but instead be based on the provided timing information.

See

interface FrameAPI {
    registerFrameListener(listener: FrameListener): void;
    unregisterFrameListener(listener: FrameListener): void;
}

Hierarchy (View Summary)

Methods

registerFrameListener unregisterFrameListener

Methods

registerFrameListener

  • registerFrameListener(listener: FrameListener): void

  • Registers a frame listener which is executed on every tick of the internal update loop of the webvis context.

    Parameters

    Returns void

unregisterFrameListener