Add glTF support for the <model> tag

[UX3D-nopper]

Beside USDZ and OBJ, add glTF support.

[mrdoob]

+1

I would also suggest not supporting OBJ. Its design is just not GPU friendly.

[bhouston]

glTF support is a must these days. Just like tag supports jpg, png, webp, the tag should support at minimum usdz, and glTF for high quality models. Lower quality models I guess can be stl and obj.

BTW I am a very strong supporter of the tag, I tweeted the reasons here: https://twitter.com/BenHouston3D/status/1432685072256208896

[gsnedders]

Do you foresee anything being needed in the explainer (or future specification) for this? At the moment, there isn't per-se any support for USDZ/obj: a source element can be provided for any file format, and the same is true for glTF.

If this is about WebKit's implementation, please file a bug on bugs.webkit.org.

[donmccurdy]

Do you foresee anything being needed in the explainer (or future specification) for this?

#67 might be a good example. Boolean autoplay may be ambiguous if the model contains multiple animations, which glTF models often do. Standard practice in glTF viewers is to play the first animation by default, and (ideally) provide some means of selecting others. More complex composition is possible but perhaps out of scope here.

[othermaciej]

It definitely makes sense to support features of common model formats; the explainer is otherwise intended to be format-agnostic, and specific formats are mentioned only by way of example.

[tonyparisi]

100% glTF is a must-have. How is this team deciding which formats to support natively?

[tonyparisi]

It definitely makes sense to support features of common model formats; the explainer is otherwise intended to be format-agnostic, and specific formats are mentioned only by way of example.

Maybe so, but I think it sends a confusing message to readers that the most open format, and the most widely adopted for this use case, glTF, isn't shown in the examples. It would be very easy to add .gltf and/or .glb in the example.

[tinanigro]

glTF not being added in the code examples currently sends a messaging close to “we will force web developers to use either an aging (obj) or competing (usd) format, since we won’t support glTF in Safari”

that’s how I read it. Would 💯 to be wrong, though…

[grorg]

To be clear, we're not deciding which formats are supported. Those were just example code snippets.

I'll add glTF and remove obj from the examples.

[grorg]

BTW - if someone could make a gltf version of the example USDZ file I'd be very grateful. I had one, but I can't find it at the moment.

[donmccurdy]

Thanks @grorg — I've opened #70 with a .glb version.