Previewer unification

[avaer]

Background

Right now we have three main previewer endpoints (HTML files which you can load to get previews functionality):

• https://github.com/webaverse/app/blob/master/preview.html (previously used to do local rendering in iframe, now superceded by OffscreenEngine which is far more capable)
• https://github.com/webaverse/app/blob/master/screenshot.html (the core engine used by the preview server, responds to URL requests)
• https://github.com/webaverse/app/blob/master/pic.html (a new admin-centric preview generator)

Problem

There are too many divergent preview implementations. In fact, most of the above are (probably) not used.

Most of the logic for these now lives in many separate imporable preview engines like object-spriter.js. The engine is successfully using these already and we will probably encapsulate more preview engines like this.

Here is a non-exhaustive list:

Scenes

https://github.com/webaverse/app/blob/master/scene-cruncher.js https://github.com/webaverse/app/blob/master/scene-previewer.js https://github.com/webaverse/app/blob/master/scene-screenshotter.js

Objects

https://github.com/webaverse/app/blob/master/object-spriter.js

Avatars

https://github.com/webaverse/app/blob/master/avatar-cruncher.js https://github.com/webaverse/app/blob/master/avatar-spriter.js

Solution

• Stabilize preview engines we might need, like the ability to PNG and avatar
• Reduce the amount of preview pages to 1, probably called preview.html, though having nothing to do with the previous code
• Make the preview.html use importable preview engines
• Move preview-related code to a separate directory tree

[avaer]

Note that in some cases (such as scene crunching), the output is a GLB, not an image.

So a previewer UI will need to have a small renderer to explore such outputs.

[avaer]

All of this can be imported into the marketplace/dashboard.