We need to soon have a plan for bioluminescence implementation as once radiotrophy (and maybe full thermoplast) implementation, it will be the next feature for me to implement. And I just realized there’s not even a discussion thread about it.
So here’s off the top of my head what has been talked about on Discord (and what I think is doable to implement):
Bioluminescent vacuole will be in visuals pretty similar to the normal vacuole but will use bloom effect to seem like it emits light (for rendering performance cost I don’t want to have actual lights attached to the cells)
The vacuole should probably be only effective in low-light areas / during the night
Then the hardest part will be to decide what effects it would have. We need to be reasonable here due to constrained development resources.
It was already talked about how realistically a microbe can’t produce any significant light (so I think any photosynthesis effect should be out of the question), but to make at least some interesting gameplay here are some ideas:
The light could attract other cells. Either predators or maybe photosynthesisers as well? That way predators might evolve it as well.
It could have effects like the signalling agent that it attracts just other cells (kind of the same as above but various more conditions)
It could offer protection against oxygen (by like acting as an oxygen burning organelle that incidentally makes light). This would mean the part can only be added after environmental tolerances.
Then whatever is picked for the gameplay part, we’ll need at least some kind of related modelling of it in auto-evo.
Does that sound like an okay plan? Are there more ideas for what the effects could be?
While it is a good gameplay mechanic (we don’t have much luring stuff at the moment), I don’t think it’s that realistic. As you mentioned emitted light from only one cell in isn’t viable for photosynthesis so there is no reason for photosynthesizers to move towards it. And cells don’t have eyes (unless some light-detecting pigment that I think was talked about before) so they can’t see the light. And even if they saw it there wouldn’t be much reason to go to it to my thinking. Unless we make bioluminescent vacuole be able to generate stronger light (by quantity for example) to attract photosynthesizers. I just googled and anglerfish lure plankton like that, that lures fish that feed on it in return.
Membranes with half (?) emission (bottom left - without):
It probably can look better if someone with more experience with shaders would do it but I think the general idea seems fine. I was thinking of something like rays coming in all directions from vacuole like a beacon, but real-life bioluminescent cells don’t have such strong light (on images on google) so I’m not sure about this idea anymore.
I think it was said before that bioluminescence could only affect cells that have thylakoid for example (as they should then technically be able to detect the light). But that would very greatly limit the potential ways it is used. So I think that requirement should be left out for that reason.
I just think we need to reduce the expectations of realism on the bioluminescent vacuole, because otherwise the whole organelle just needs to be entirely scrapped as there was no way to implement it. And I think it would be “not optimal” to scrap an organelle that we have had in our list of organelles for 8+ years at this point claiming it is going to be implemented sometime “soon.”
As far as I know during the great oxidation event bioluminescence was a way to avoid oxygen. So it might as well be a way for early bacteria to keep their hydrogenosomes in tact.
I’ve been thinking about a way to use both Light Emitting Vacuoles and Eyespots. First of all, the Light Emitting Vacuole (LEV from now on):
Increases tolerance to oxygen (once environmental tolerance has been added). I think this should be there regardless of other effects.
Attracts some cells with phothsynthetic organelles or an eyespot.
For multi-celled organisms, also acts as signalling agent.
I’m going to propose that the Signalling Agent’s effect be changed slightly. It doesn’t make sense that the chemicals sent out from this reach all friendly cells instantly. Instead, each cell would have a delay before responding. The length of the delay depends on the distance from the source of the signal. The LEV on the other hand, has no delay - it would have an instant effect, just like the current signalling agent.
I also propose that we add a new stat - Vision Range - that determines the maximum distance at which cells can detect things. For the player, this would determine the maximum distance the player can zoom the camera out from their cell. For AI cells, they would only be able to detect cells, clouds and chunks within their VisionRange, except for things their Chemoreceptors are tuned to, or that are visible to their Eyespots at a greater distance. This would affect cells in the world and Auto-Evo results.
The Vision Range would start off low, and would increase with orgnism size, up to a limit. Adding a Chemoreceptor to the cell would increase Vision Range, and adding an Eyespot would increase it further.
And finally, the Eyespot:
Increases Vision Range (max zoom level).
Makes LEVs visible: without it, LEVs do not display emission (i.e. they would not glow) and AI cells cannot respond to them.
Makes daylight visible - without it, surface patches would always look like it’s night time.
Could also provide highlights or icons at the screen edge to indicate things visible further away (e.g. large chunks, dense clouds, very large cells and LEVs). In this regard, the Eyespot would function like the Chemoreceptor, but could show multiple objects of different types simultaneously in a less targeted way.
