It’s getting a color off anywhere on the game canvas that’s not reliably possible with webgl without some changes to the runtime. Getting a color off the pasture texture with webgl however is possible, and actually the webgl snippit in that link is close to how it would be done.
It’s not something I’m willing to do though. There are too many more fun ways to spend my time.
Anyways, cheers to black hornet for porting it to a c3 addon.