[Cycles] Hard Volume Textures

http://blender.howto.cz/blender-links/Cycles-Volume-Tex/volume-tex-01.jpg
http://blender.howto.cz/blender-links/Cycles-Volume-Tex/volume-tex-02.jpg
http://blender.howto.cz/blender-links/Cycles-Volume-Tex/volume-tex-03.jpg
http://blender.howto.cz/blender-links/Cycles-Volume-Tex/volume-tex-04.jpg
http://blender.howto.cz/blender-links/Cycles-Volume-Tex/volume-tex-05.jpg
http://blender.howto.cz/blender-links/Cycles-Volume-Tex/volume-tex-06.jpg
http://blender.howto.cz/blender-links/Cycles-Volume-Tex/volume-tex-07.jpg
http://blender.howto.cz/blender-links/Cycles-Volume-Tex/volume-tex-08.jpg
http://blender.howto.cz/blender-links/Cycles-Volume-Tex/volume-tex-09.jpg
http://blender.howto.cz/blender-links/Cycles-Volume-Tex/volume-tex-10.jpg

Very interesting!

anything about the pipeline?

So damn beautiful!

Nice. Could you post the nodes setup?
I’ve experimented the cycles volume a few days ago but couldn’t figure it out to use it.

there is not much to say from my side . . . change texture type node and play with setups . . .

http://blender.howto.cz/blender-links/test-Volume-Tex/Volume-Tex-Node.Setup.jpg
“Graeter Than” node sets greyscale texture to black&white. Value changes position of “edge” (where black ends and white begins) like Ramp-Constant in internal texture pallet.

For heavy and sharp volume change Density=0 and Volume Cell Step to minimum as it’s possible.
http://blender.howto.cz/blender-links/test-Volume-Tex/Volume-Tex-Integ.Setup.jpg

Would be great if someone can explain how does all these setups works. I just moved sliders.

Download .blend File

thanks a lot. “not much” but enough for me to figure it out. I was missing the transparent surface shader.

Kewl pictures!

@renatogsousa: Surface doesn’t has to be only transparent you can mix it with any other shaders

http://blender.howto.cz/blender-links/test-Volume-Tex/volume-tex-11.jpg
http://blender.howto.cz/blender-links/test-Volume-Tex/volume-tex-12.jpg

Just one thing I noticed - when I tried to use the same texture (with same coordinates) as volume and surface it doesn’t match in the same position. (It’s not shown in this images.)

Amazing!!!

Thanks!

paolo

I am going to need a faster machine.

I got it!

This is really neat stuff, Storm St. And you created these patches? I’m really impressed.
My question is, will this allow for smoke? I had been experimenting with smoke sims in BI, but Cycles had never been able to do volume before. Till now, it appears anyway.
So, this would let us do smoke sims in cycles?
I’m going to go try it out now.
Thanks for all your hard work and ingenuity Storm St. From what I can tell, this has made you a Rockstar of Blender.

Thanks for nice words.

There is no 3D image textures support in Cycles, it related to CUDA/OpenCL features as i remember Brecht note long time ago. You can plug some wild procedural texture to Density socket as temporal test workaround, but that is all. And it will be very slow compared to current BI smoke system, it will looks cool with all that full multi scattering, but not usable, you will spend months per frame to clear noise. It more like reference implementation that can be used to debug maybe faked, biased but practically usable solution.

but not usable, you will spend months per frame to clear noise. It more like reference implementation that can be used to debug maybe faked, biased but practically usable solution.
How many Weather Cartoons do I have to make to prove that Volumes converge within a reasonable amount of time on a CPU? :slight_smile:
At worst, only a few hundred passes are needed to clear (homogenous)volumes, and if you’ve been keeping track of my daily cloudmap splashes, textured volumes aren’t that hard either.
Seriously, it’s not uncommon for other elements of a scene to take longer to clear up than the volume.


Would be great if someone can explain how does all these setups works. I just moved sliders.
Density geometry factor is pretty much the scaling of the volume. It’s hard to explain, but have you noticed how if an object is larger, it appears more dense, even if the shader’s the same? That’s because it contains more volume “particles”. Sometimes, it’s annoying when you want a small object to be very dense, but it stops at Density = 1, so you can turn down the Density Factor to make the small object appear larger to the renderer, and thus more dense.

Take a look at these hurricanes:

The hurricane at 1/100th it’s original size:

http://www.pasteall.org/pic/show.php?id=24201

And here is the hurricane at 100x its original size:

http://www.pasteall.org/pic/show.php?id=24202

Volume Cell step like the resolution a 3d texture is rendered in. Storm can correct me if I’m wrong, but I think that an object is sliced up into lots of tiny volume cells, and the 3d texture determines how dense each cell is. The smaller the cells, the more fine the textured volume will appear. Step only affects the volume if you use Constant Cell Marching(Sampling Algorithm 0), with Woodcock(Sampling Algorithm 1), it’s irrelevant. (I think maybe iterations is like that for woodcock, don’t know.)

@storm_st: thank you very much for your amazing work on volume shader !! :slight_smile:
With multiplication, I will take a look, It sounds interesting.

@OL77: thanks for explanation, cell step was clear to me, but what about others? :slight_smile:

Anyway does anybody know how to create doted volume? Thanks

So what build has these extra fields for the Integrator?

I pulled down build r43660 and those options do not appear in my panel?
.
.
.
Ah, got it this one (at least for Windows)

Attachments


Magic Texture was for me always strange looking texture with crazy colors :slight_smile: So yesterday I was supprise that we can set this testure for bands, tubes or dotty texture as well . . .

http://blender.howto.cz/blender-links/test-Volume-Tex/Volume-Tex-Magic-001.jpg
http://blender.howto.cz/blender-links/test-Volume-Tex/Volume-Tex-Magic-002.jpg

http://blender.howto.cz/blender-links/test-Volume-Tex/Volume-Tex-Magic-003.jpg

http://blender.howto.cz/blender-links/test-Volume-Tex/Volume-Tex-Magic-004.jpg

This all looks awesome. Does anyone know when it will be merged into SVN?

On my last screen I noticed there are missing some parts of a volume tubes.
So, for those who need solution: with low “Volume cell step” value you need to set “Volume max iterations” higher.

http://blender.howto.cz/blender-links/test-Volume-Tex/Setup-note-01.jpg