Use identicons to identify players

[MatthewWilkes]

This adds a new use_identicons config variable to griduniverse that causes players to be textured with an identicon based on the experiment id and the player id.

It rewrites the shader quite significantly, and changes the general approach to use triangles rather than points. I've tested in Chrome and Firefox and it's working well, but there are warnings generated by WebGL about texture indexes. I suspect this is a race condition, what I've read about this error suggests it manifests as flickering but I don't see that, so I think what's happening is the shaders are being run before the textures are fully uploaded.

[MatthewWilkes]

Hmm, interesting. Are you using a mac? It looks like there is a much lower limit in the mac graphics drivers than Linux.

I'll have to have a think about how to solve this, other than limiting it to 15 visible identicons at once.

[suchow]

@MatthewWilkes Indeed, using a mac, macOS Sierra 10.12.5.

[MatthewWilkes]

Okay, I'll crack a mac out and investigate.

[jessesnyder]

I tried pushing just 10 textures into the all_textures array and this allowed me to move forward with testing. It looks pretty awesome.

[MatthewWilkes]

I think the solution will be to build one very large texture and change the coordinate mapping instead of the chosen texture.

[suchow]

In regard to identicon appearance: the original version had colorful backgrounds and muted shapes, this version has a black background and colorful shapes. I think what we want is a muted background and a colorful shape. That has the benefit of taking up the whole cell (which makes the solid trail more reasonable looking) without the low-contrast issue of the original.

[suchow]

Beautiful: