Add 'expected render' screenshot of each model in readme table

[stevk]

• Generate screenshots/gifs
• Insert images into readme tables

[bwasty]

Do you have a tool yet to generate the screenshots?
I quickly wrote a script for my gltf-viewer: bghgary@5f6be5c
Here are the results: https://github.com/bwasty/glTF-Asset-Generator/tree/gltf-viewer (see subpages with reference images).
A few images are missing/wrong because some features are not implemented yet (primitive modes, TEX_COORD_1, alpha mode + cutoff ... bwasty/gltf-viewer#3)

(And I had to do some small adjustments to camera and light: bwasty/gltf-viewer@56604b0)

[bghgary]

Yes, @kcoley is working on a screenshot generator, but it will be specific for generating reference images based on BabylonJS.

I'm assuming you are asking because you want to compare the results from your implementation against the reference. I discussed this a bit with the Khronos working group. I think it makes more sense for each implementation to do this work. We can possibly create a new repo that include some test harness code to help with web implementations.

[donmccurdy]

^One extra thought from my suggestion of adding URL of reference screenshot in the manifest, perhaps we also include the camera transform? Would make it much easier for other implementations to match.

[bghgary]

perhaps we also include the camera transform?

Hmm, interesting. Let's review this once we have the reference images.

[bghgary]

This is complete.