The main characters of Grow Together are these little egg-shaped hovering Xenobiologists, shown in some sketches below.
I wanted to recreate this in Unity, so I made an egg-shaped little mesh, added some eyes, and then added a sphere below the character where I wanted to render the electric hover-lines.
To make this sphere turn into a hoverfield, I used Unity’s ShaderGraph to make the sphere transparent in all places except a thin set of vertically-striated bands, where it emits a blue hue.
Shadergraph is one of my favorite features of Unity, because it’s such a visual tool for designing effects. Every effect that you add to the graph can be visualized–as you see below.
To walk you through this graph, I’ll start with the top-left chain: this chain uses Gradient Noise (aka Perlin Noise) to create the striation effect on the hover field. Essentially, all it does is define a very horizontally-skewed version of this noise, where white corresponds to a striated line, and black corresponds to a transparent patch, and then moves this noise slightly every timestep to create a sensation of movement.
The middle chain creates thin bands using a Sine generator–again, the white lines are where the force field will show up–and makes these thin bands move downward slowly over time, to give the sense of hovering. We add the top two chains together, and voila! A full spherical force field:
The bottom chain simply makes this force field appear only in a thin band about 2/3 of the way down the sphere, so the force field lines don’t come straight out of our Xenobiologist, and also don’t disappear into a single point at the bottom of the sphere. To me, this looks more force-fieldy:
Obviously, there’s a lot more that could be done here. It would be cool to give a player real control over the colors of their Biologist, and also even different force-field effects. I was originally hoping to make something that looked more like a circular plasma (see the sketches above), rather than more of an ion-field effect, but it turned out to be much more difficult than I expected. Maybe later I’ll spend time on creating alternative effects.