Builds not flooded under water

[KoshCape]

I would like to suggest to be implanted, a resource, where the water and the object that was in the water, its interior remained dry, not flooded; and the flooding system was implemented, and for some event it could simulate the RL, a problem, its solution. An underwater construction should be dry, if it does not have openings for water to enter. the same in a building, which is being built under the sea, the construction finished, the water could be drained having a space separating a building with the maritime exterior. That is, this construction being a solid object and the water did not dare its walls entering its interior with the same without having openings.

[Rowan Amore]

3 hours ago, KoshCape said:

I would like to suggest to be implanted, a resource, where the water and the object that was in the water, its interior remained dry, not flooded; and the flooding system was implemented, and for some event it could simulate the RL, a problem, its solution. An underwater construction should be dry, if it does not have openings for water to enter. the same in a building, which is being built under the sea, the construction finished, the water could be drained having a space separating a building with the maritime exterior. That is, this construction being a solid object and the water did not dare its walls entering its interior with the same without having openings.

Might be worth a read

 

[Profaitchikenz Haiku]

(deleted, linked post says it all)

Edited February 24, 2021 by Profaitchikenz Haiku

[Beq Janus]

Given that the build in the thread linked above is mine I can explain a few basic rules.

Building underwater in SL is all about suspending disbelief and convincing your eye that things are not flooded. Under water shaders have a fog setting that kicks in sooner than on land and therefore the most important rule is to distract the eye from noticing the water fog by not having long views in large open spaces. A long narrow, well-lit tunnel will still look ok and a large room with lots of architectural substance will also add enough visual keys for your mind to accept that this is a living space.

It is all optical illusion. 

Here is a short clip of the main undersea tunnels, these are a real challenge because they are long and straight, to highlight the difference between inside and out the glass is tinted and the inner space is well lit. I take my camera outsside into the sea and into my own "airlock". The airlock is flooded (don't worry I am good at holding my breath) and if we cam to the airspace at the top of the airlock we can seea a "fake" water surface.

https://i.gyazo.com/d0fd30664178ef9a81a7d86c169f06fe.mp4

 

The next clip shows how the fake water "drains when the airlock is closed. 

https://i.gyazo.com/5dbce46695375c0d1ccb7613bb51527c.mp4

This build is ancient and technically dated. I built it in ~2008. It is predominantly prim and some sculpties but it demonstrates a few tricks we can still use. 

There is more that can be done these days to make the effect more visually compelling but it works well enough for a 13 year old build

What could be done in the viewer to make underwater work better?

One option might be to allow a special volume type, that could be used to identify interior spaces, this would not be water physics, just a trick to allow the viewer to know what shaders to use. It is not clear to me though if that would achieve what we want ultimately. the viewer could in theory determine that it was inside the special volumes and use push a differnt set of shaers to the usual underwater ones, but that would address just the "indoors" aspects. 

If you have spent any time in RL underwater as a scubadiver then you will be aware that your perception of light is not the same as that of a camera. It gets dark very quickly, your brain automatically corrects (to some extent) for the attenuation of light and the elimination of certain parts of the spectrum as you go deeper. An underwater photo without artifical lighting will be a dark, blue tinted drab thing and any decent photos need to be well lit. Would people actually want this to be how it worked? Some would, many would not, I suspect.

With light attenuation we'd also want caustics, these are the lighting artefacts that even non-divers will have seen when snorkelling and swimming, ripples and shimmers upon the sand.These are quite onerous to render.

Here is a little article on how sub-nautica deals with this. Keep in mind that sub-nautica is quite literally focussed on underwater and so can afford to throw a lot of rendering effort into this. In SecondLife (sadly) the underwater world is not well loved by most residents. Though we might argue this is a self-perpetuating, all the time we neglect the undersea we are not going to attract people to it.

https://www.gamasutra.com/view/news/264997/How_Subnautica_plunges_deeper_into_rendering_realistic_water.php

 

 

 

 

[animats]

This came up once at Creator User Group. I think Vir Linden mentioned it. Boats can't keep water out, and so boats tend to be awash with water inside the hull. Or they ride too high in the water, to avoid that.