It's very cool!
The most interesting results I got were from having multiple "variants" and giving each variant parameters for their attraction to agents of their own/other type. Implementation-wise it was a variant tag for each agent and a matrix of attraction coefficients as a uniform. Playing with the params resulted in interesting behaviors, like one variant chasing another around while they both try to avoid a third.
If you're looking for an addition to this project, I'd recommend giving it a try!
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Just like iphones get the latest/newest features after top of the line Androids.
Unfortunately, the demo itself is not responsive to the screen size.
Why someone would want to simulate a slime mold is something I don't understand, but more power to ya. =)