aframe-layers-component

This is an A-Frame component for controlling the layers of an entity.

Why is this useful? In VR, sometimes you want to show things to one eye but
not the other (stereo panoramas for instance). This can be done by restricting
an Object3D to either layer 1 (visible to the left eye) or layer 2 (visible
to the right eye).

- Demo

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| Property | Description | Default Value |
| :------: | :-----------------------------------------------------------: | :-----------: |
| layers | An array of layers the entity should have enabled e.g. "0, 1" | "0" |

Note: omitting layer 0 will likely cause your object to disappear (unless you enable additional layers on the camera).

usage

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Install and use by directly including the browser files:

``html














layers="1"
position="-1 0.5 -3"
rotation="0 45 0"
color="#4CC3D9"
>


layers="2"
position="1 0.75 -3"
radius="0.5"
height="1.5"
color="#FFC65D"
>
position="0 0 -4"
rotation="-90 0 0"
width="4"
height="4"
color="#7BC8A4"
>




`

This code generated the image shown at the top of this README. In VR, the blue box is visible to the left eye only while the yellow cylinder is visible to the right eye only. Outside of VR, neither the box or cylinder are visible because the camera defaults to layer 0 only.

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Alternatively, install via npm:

`bash
npm install aframe-layers-component
`

Then register and use.

`js
require("aframe");
require("aframe-layers-component");
`

local development

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- node.js and npm
- OpenSSL (if HTTPS is needed for local dev)

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1. Clone this repo
2. npm install

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`bash
npm run dev

if https is needed


npm run dev-ssl
`

This will start a local dev server.

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Once new features/bug fixes are merged into master.

1. Increment package version in package.json (semver is recommended).
2. npm run dist
3. Commit the newly generated ./dist files.
4. npm publish
5. Update jsdelivr CDN links in this README to point to new version.
6. Draft a new release on GitHub, add a changelog describing what has changed since the last release.

references

This component was originally based on Óscar Marín Miró's stereocam component.

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In three.js, Object3D have a layers` property that can be used to control visibility.

> ...an object must share a layer with a camera to be visible when that camera's view is renderered. - three.js docs

By default all Object3Ds are a member of layer 0, so everything starts out visible. In VR mode, each eye is represented by a separate camera and given access to an additional layer:

- the left eye can see layers 0 and 1
- the right eye can see layers 0 and 2

This makes it easy to do things like show meshes to each eye independently--a necessary trick to view stereo panoramas.