The Moon and The Crust

[Sami]

Erkka was visiting me last weekend and some really exciting weather engine achievements and accompanying real life adventures were made.
Now there are two new essential weather features on the table - both still somewhat under construction, but most likely to be seen in the next version.

And the features are...

* The moon.

Our weather engine now models the moon in detail, with its' changing phases and moonlight affecting to the nighttime visibility and brightness.
Lots of tuning is still pending, but we can already see that the full-moon nights in the game will be a different experience.
Especially during the darkest seasons moonlight can be a of great help and extended the available hours for working, hunting or travelling.
Just have a look at the screenshot compilation below.


Left: A casual midnight by the lake in dirt month as it appears currently in the game.
Right: The same scenery with the new moon code in action. It's full moon and our nighttime visibility is a much different.


* Snow crust

Snow crust is a springtime phenomena where surface of the snowpack becomes so hard that it can completely support a walking or skiing person.
The crust results from partial melting of the snow surface by warm spring day sunlight followed by re-freezing when the temperature drops again, usually after the sunset.
The crust normally only lasts for part of the day, but being able to travel on snow without sinking in there at all is a great asset for a hunter.
Elks were traditionally hunted on skis during crust as it can't support the heavy animals and hunter gliding on crust with skis now became much faster than their prey.
Lots of work is still needed before snow crust support is all coded, but that's the intention. Now it also requires proper snow penalty to be added for NPCs and animals, and reworking the skiing code to some extent too. (And if you were thinking of skiing NPCs so were we.)


The last weekend it was both full moon and snow crust possibility, so we also went experiencing these things in real life.
Naturally these both are familiar experiences already, and as countryside kids we've learned possibilities of snow crust for work and leisure all the way from our childhood.
But if you'd like to see the magic of skiing in moonlight without any artificial light, or get an idea about difference between skiing in slushy spring snow compared  to the crust, we've got a short videoclip for you:

https://www.youtube.com/watch?v=JOcb_cm5UkE

[Ara D.]

Love the moon light wondering if you also were going to add in cloud effects? While and overcast day wouldn't effect visibility there would be a huge difference between clear full moon and on one a cloudy night.

[Sami]

Love the moon light wondering if you also were going to add in cloud effects? While and overcast day wouldn't effect visibility there would be a huge difference between clear full moon and on one a cloudy night.

Yes, the cloudiness is also taken into account, as well as the lunar phase. It all contributes to how much extra light there will be.

[trowftd]

Wow! It sounds like the new update is coming along nicely. The immersion in nights will be a lot better. And the fact that stuff like snow crust will be simulated is amazing, it should make night time hunting way more interesting. I love the attention to the detail in nature in this game.

[Brygun]

Cool

Realistic and lived details like this is why whenever I try any other "survival sim" I kept saying UrW does it better.


You an quote me on that.

[Plotinus]

Wow that's amazing!

[Matti-patti]

Moonlight cycle and animal and NPC winter movement being normalized with the player sound great. Overall looks like next one is turning out to be quite an update.

[Homocommando]

* The moon.

Our weather engine now models the moon in detail, with its' changing phases and moonlight affecting to the nighttime visibility and brightness.
Lots of tuning is still pending, but we can already see that the full-moon nights in the game will be a different experience.
Especially during the darkest seasons moonlight can be a of great help and extended the available hours for working, hunting or travelling.

I think snow should also affect visibility, since it is white, and reflects light well. When there is snow, it is much easier to see, than at night in summer.
I didn't see snow for a long time , but if I remember correctly I could see almost everything at night, when there was snow.

[PALU]

As you say, there's a significant difference between the presence of snow and the absence of it during the dark parts of the year. While you can't see anything when it's pitch black regardless of the presence of snow, its presence when there is some light has quite an effect. A full moon over snow provides a fair bit of visibility, while a low sun over snow is blinding (snow blindness is a thing).

However, around the summer solstice it's possible to see fairly well during midnight without a moon because the sky is so bright. During the winter, snow can't make up for the pitch black sky, only compensate a little for the long dark hours.

[Erkka]

In UrW simulation there are two factors to the visibility:

1) how far you can see
2) how bright / dim is the area you see

(there, naturally, is a defined relationship between these two. But, speaking of the simulation, they are different variables)

If we use these variables to make sense of the real world phenomena, I think moonlight having snow on the ground doesn't affect variable 1. But it might slightly change variable 2. The main effect of having snow on the ground is that it creates a different kind of contrast. Let's imagine it this way:

there is no snow on the ground, you are standing on a middle of a field, looking at the edge of the forest. Next to the forest there is someone, maybe a person, maybe an animal. But the forest behind that creature is dark in color, and so is the creature. So you have very little of visual cue to distinguish the dark shape of the creature against the dark background.

Now, imagine the same scene with snow on the ground, and also a layer of snow on tree branches. Suddenly the background appears not dark, but more like dimly glowing blueish-white. But there is not snow on the creature, the creature is dark. In these conditions it is a lot easier to spot "aha, there is something there, near the edge of the forest!"

And I think something like this happens in UrW simulation, too.

[Evuul]

Love the moon light wondering if you also were going to add in cloud effects? While and overcast day wouldn't effect visibility there would be a huge difference between clear full moon and on one a cloudy night.

Yes, the cloudiness is also taken into account, as well as the lunar phase. It all contributes to how much extra light there will be.

This is a mind blower, awesome work Sami!

[Sami]

Love the moon light wondering if you also were going to add in cloud effects? While and overcast day wouldn't effect visibility there would be a huge difference between clear full moon and on one a cloudy night.

Yes, the cloudiness is also taken into account, as well as the lunar phase. It all contributes to how much extra light there will be.

This is a mind blower, awesome work Sami!

And Erkka too. This greatly a two-man team effort.