A natural situation

[yonosoy]

Thanks for the tip, now it is necessary an email to send the message.
I don´t know where to send the scene; please someone...

[OnoSendai]

nick@indigorenderer.com, thanks!

[yonosoy]

Sended. Thanks.

[Tramis]

Since you guys are on it, here some related papers out of my private collection

Clouds
A Simple, Efficient Method for Realistic Animation of Clouds
Physically-based Cloud Rendering on GPU
A Real-Time Cloud Animation and Illumination Method
Interactive Cloud Rendering Using Temporally-Coherent Photon Mapping
Volumetric Clouds
An Inverse Problem Approach for Automatically Adjusting the Parameters for
Rendering Clouds Using Photographs

Sky
Real-Time Spectral Scattering in Large-Scale Natural Participating Media
Rendering Parametrizable Planetary Atmospheres with Multiple Scattering in Real-time
Predicting Sky Dome Appearance on Earth-like Extrasolar Worlds
Adding a Solar Radiance Function to the Hosek Skylight Model (scroll down!)
An Analytic Model for Full Spectral Sky-Dome Radiance (scroll down further!)
New CMFs and More Accurate Spectrum Renders
Physically Based Atmosphere Rendering
A Critical Review of the Preetham Skylight Model
Efficient Spherical Harmonics Lighting with the Preetham Skylight Model
A Practical Analytic Model for Daylight
A Physically-Based Nightsky Model

I hope you don't mind that spam, I usally only bomb Thomas with that stuff

Cheers mate!

[Vrender]

Looks nice!
Thanks for the tip!
tell me please where you can download Indigo scenes examples? Exterior an Interior

[sam mcfly]

Hello guys,

i'm trying to make a space scene with Saturn but i can't simulate the atmosphere, i use blendigo.

is there a material that could do it?

Thanks.

[yonosoy]

Hi. Yes it is possible to simulate some kind of atmosphere for a planet. This post start up when we realized that indigo do this kind of jobs. A quick aproximation is to play with henyey-Greenstein phase, like in this example.

Code: Select all

<henyey_greenstein>
								<g_spectrum>
									<rgb>
										<rgb>0.9 0.8 0.35</rgb>
										<gamma>2.2</gamma>
									</rgb>
								</g_spectrum>
							</henyey_greenstein>

The IOR is 1, the absorption value is 0, the scattering value is of 0.000001. The values for rgb gives you a meant of colour (bluish in this case).
Remember to use simple path tracing for a volume of this characteristics (like for atmosphere). Remember too that you can´t change the values for the medium in the GUI, because the medium changes from henyey-greenstein to uniform phase (reported some times before).
This message appear when i try to upload the igm file:
"The upload was rejected because the uploaded file was identified as a possible attack vector."

Hope this helps. Cheers.

[sam mcfly]

thank you, but do i need to create a new sphere and make this material?

or can you upload it as an external material (.igm)? so i can use it in blendigo, thanks

[CTZn]

thank you, but do i need to create a new sphere and make this material?

or can you upload it as an external material (.igm)? so i can use it in blendigo, thanks

You can get to the IGM by renaming the PIGM as a ZIP file and extract its content.

Well done yonosoy. Of course at some point I started a fully procedural approach but it went stalling. I did actually

[sam mcfly]

Thank you.

But i don't see any difference. Do i need to set my sphere with the real radius of saturn?

[yonosoy]

Hi Sam, sorry for the delay (not at work lately).

The procedure is this:
Take a sphere (not perfect, usually i used the icosahedron one). This is the planet so take a right spherical texture and do a material, an oren-nayar or a diffuse or even a phong with a very low exponent (you speak about Saturn, I think that is the texture I use for the example).

You need then another sphere for the atmosphere. In the case of Earth, it has 80 km. of high. Maybe try to read about for the correct thickness of Saturn (in the example I use 50 km.) Apply to this sphere the material uploaded.

SPHERE A (planet) = radius A ; SPHERE B (atmosphere) = radius A + atmosphere thickness

Indigo is a light simulator that take in account every step in physics. Is important to model at real scale. The material uploaded is for the right dimension of Saturn. In this singular case you can model the scene in another scale (try to regulate the amount of SSS (in the example, for the right dimension of Saturn I used 0.0000001)). It was a quick approximation, refine it.

Hope this helps; if you have another question, do it!

[sam mcfly]

I tried it, and it works fine thanks for your help

[yonosoy]

Two not finished. Just remembering some possibilities for this kind of scenes (a sphere, a box and a plane).

[OnoSendai]

Stunning!

[Oscar J]

Awesome. What are the render times for these?