Wednesday, July 13, 2011

Alien planet Earth

Rendering our planet "alienized", using a different set of basic materials for fractal mixer, with changed parameters of atmosphere, sun and water.

Scattering of light in the atmosphere determines both the color of sky and sunsets. We can see a blue sky because the blue light is more likely to bounce off the air molecules than the green and even more than the red components of sun light. As the light from sun travels through the atmosphere above us, some of it gets scattered away from the ray and towards our eyes. The same effect is responsible for red sunsets - as the sun sets, light from it has to travel a longer way through a denser layers of atmosphere. By the time it reaches us, most of the blue and green light gets scattered away from the ray, leaving only the most persistent red component.

This effect is simulated in Outerra, and so we are able to play with it. What if the atmosphere consisted of different gases and the scattering characteristic was different?

In the following video we are showing planet Earth that was "alienized". The atmosphere in it scatters the green light best, which you can see not only on the sky itself but also on the shaded parts that are not lighted by sun but only by a portion of the sky.
The sun has got an orange shade, which you can see mainly on the horizon (the sun itself is too bright so looking at it directly saturates the color to white).

The absorption of light in the water has been altered as well - normally, the red light gets only so far in the water, when it almost entirely disappears. Here, the medium absorbs the green and blue light instead, letting the red one to penetrate into depths. Of course, since the water surface largely reflects the sky at an angle, the ocean appears to be green in the distance.

At the end there's also a short sequence with a red-orange atmosphere.


Here are some screens showing it under various settings:

http://www.outerra.com/shots/alien/alien1.jpg

Milk water & yellow skies:

http://www.outerra.com/shots/alien/alien3.jpg

Violet atmosphere:

http://www.outerra.com/shots/alien/alien4.jpg

No atmosphere (or no atmospheric scattering). This is what you'd get for example on the Moon:



http://www.outerra.com/shots/alien/alien5.jpg

3 comments:

KortoloB said...

Your engine looks amazing. How big could you practically make a "map"? Could it include a whole solar system to scale or maybe even a galaxy?

Outerra said...

Well, technically it's not limited, but we are focusing on our planet, at least initially. Later we would like to expand to nearby moons and planets, in a gradual colonizing way.

There are other engines and apps like the Space Engine, that focus on the bigger scales first, we are taking on it from the bottom :)

Alex said...

Looks awesome as always :D

I especially like the violet one, though it doesn't look alien at all.