Motile v. Sessile Pathways in the Transition Between Microscopic & Macroscopic

[Rathalos]

@Deus

It’s a tricky question: we need to have some modicum of theory behind our decision, but the microscopic-macroscopic jump will be one of the most abstract and gamey parts of Thrive by necessity.

I actually have some decent hope, depending on what we can get implemented in Multicellular, that we can do a pretty intuitive transition. In theory every cell part and attribute from Multicellular can translate to a Macroscopic feature, even if the effects they have are different (in fact, I think that would be fun).

@Deus

With how complex and large the jump between the microscopic and macroscopic world will be - and how the macroscopic will in many ways be a completely new game - I think we ought to make sure as many binding choices leading into the Macroscopic are as intuitive as possible.

Note that this doesn’t necessarily mean that the binding choices should be wishy-washy or have easily-ignorable effects: just that a player should clearly understand if they make X choice, that means Y in the Macroscopic Stage.

I am usually a big advocate for permanent choices, but in this case I think it would be logical if a species that starts the Macroscopic Stage as sessile can still unlock the ability to become motile later on. though for example unlocking muscle should be more expensive and difficult than in Multicellular.

@Deus

• What traits in the Multicellular Stage will define a “motile” starting creature in the macroscopic stage? As in, the player will experience standard motile gameplay? The mere presence of muscular parts?
• What traits in the Multicellular Stage will define a “sessile” starting creature in the macroscopic stage? As in, the player experiences gameplay with the future “sessile game mode”? A lack of motility parts? The presence of a specific “holdfast” part?

Well, I think we should define the difference as “can you actively move in the Macroscopic stage?” with the question then becoming: What can make you move in the Macroscopic Stage?

I think we should do away with the “base cell movement” we see in Microbe and Multilcellular, that does not seem appropriate at the macroscopic scale, but other than that we have:

• Muscle: I think any kind of “muscle” cell at the end of the Multicellular Stage means that your starting Macroscopic Stage species has enough muscle to wiggle itself forward.
• Flagella/Cilia: I think having flagellate/ciliate cells also provide propulsion is a good idea.
• Slimejets: We could have slimejets convert into a Macroscopic locomotion method? I know some bacteria do this, but it might not be appropriate for Macroscopic scale?

So, if your species has one of those at the end of the Multicellular Stage, then your starting Macroscopic Stage design has the features to be mobile. Perhaps you need a certain minimum propulsion to actually be motile? In that case you should be able to fix that with the tools available in the Macroscopic editor before actually entering the gameplay for the first time? (Because you have flagella/cilia tissue, you just need to place more of it)

I think we discussed previously whether actually using these in the Macroscopic Stage would require some nerve cell type. I think that’s still an option, but perhaps it will feel awkward to not start motile even though you have those parts?

I think if you try to progress to Macroscopic without above requirements, that should trigger a warning that you will start non-motile. (and you might be able to become motile later, but this will be more difficult)

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As for sessile, I guess the biggest reason that we need to define these is for the LOD system that can populate the world with lots of static flora?

Initially, I would just say not motile = sessile. But those could technically also just be floating around in the water. So I guess it depends on whether the LOD system can handle things floating, and if we want it to.
I am guessing that the LOD system could handle things not anchored to the ground, but they would still be completely static in the gameworld, not reacting to currents. This would also mean that there isn’t much gameplay differentiation with species that actually are anchored to the seafloor.

So if we do not want to do that, we actually need a third category of “floating things”, with sessile species only being things that are actually anchored.
The obvious thing here is we do not actually have any holdfast mechanics in the Multicellular Stage, so they would have to evolve afterwards, or translate from something else in Multicellular. Lots of simple holdfasts use chemical adhesion, so maybe from slimejets/mucocysts?

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So in my opinion we either have:

• Sufficient max speed = Motile.
• Not Motile = Sessile.

Or:

• Sufficient max speed = Motile
• Not motile and has a holdfast = Sessile
• Not motile and no holdfast = Floating “sessile”

(speed that is too low “rounds down to 0”, becoming sessile)

I think if we add a system for sessile gameplay, it could handle non-anchored sessile life as well? It’s the same core problem: not much things to actively do, so you need some way to skip time.