avatarchik/sparkar-screen

Spark AR Screen is a script utility for converting coordinate and positioning object.

Screen

Screen is a Spark AR script utility for the following purpose:

1. Convert coordinate World Position, Canvas Position, Face Position to Focal Plane Position.
2. Positioning 3D object (e.g. ) by percent [0-1].
3. Scale 3D object to fit different screen size.

Install

You can download script and import it into your Spark AR project, or use this with npm.

0. Download Screen.ts

1. Drag/Import it into your project. (Spark AR support TypeScript since v105)

2. Import Screen module at the top of your script.

   import * as Screen from './Screen';

3. You can also Click Here to Download Sample Project (v115.1).

Usage

Convert Tracker's Position

const FaceTracking = require('FaceTracking');
const Screen = require('./Screen');

const face = FaceTracking.face(0);
const feature = face.cameraTransform.applyToPoint(face.leftEye.center);

(async function () {
    const position = await Screen.cameraTransformToFocalDistance(feature);
    const focalPlanePosition = await Screen.cameraTransformToFocalPlane(feature);
    const canvasPosition = await Screen.cameraTransformToCanvas(feature);
})();

Positioning with Percent

const Scene = require('Scene');
const Screen = require('./Screen');

(async function () {
    const positioning = await Scene.root.findFirst('positioning');
    positioning.transform.x = await Screen.percentToFocalPlaneX(.1);
    positioning.transform.y = await Screen.percentToFocalPlaneY(.2);
})();

Scale Object by Screen Size

It's recommanded to use this with percentage positioning.

const Scene = require('Scene');
const Screen = require('./Screen');

(async function () {
    const scaler = Screen.createScaler(9, 16);
    const scaleTarget = await Scene.root.findFirst('scaleTarget');
    scaler.autoScaleObject(scaleTarget);
})();

Coordinate Converting Included

	Canvas Position	Focal Plane Position	Percentage Position
Canvas Position to	–	✔	✔
Focal Plane Position to	✔	–	✔
Percent Position to	✔	✔	–
Face Position to	✔	✔	✔
World Position to	✔	✔	✔

Donations

If this is useful for you, please consider a donation🙏🏼. One-time donations can be made with PayPal.