Snow material in Cycles

To my big surprise, I couldn’t find any recipe to make snow in Cycles… Neither here, nor on the whole web! When you hear about snow and Cycles, it’s always about fireflies and the unwanted grain in the renderings but never about materials. At least, my Google powers failed on me. So I made my own. My first test at 200 samples:


There is still some work to do altho I found the result quite nice already. Another test at 400 samples:


My major problem is the glitter. It’s still not powerful enough to my liking and I’ve already resorted to using an emissive shader in the mix but I can’t increase the power of the light or the glitter turns to ugly when in the shadows. A glossy shader for the glittering pixels would be better… if I could “turn the pixels” towards the light! Without that, the glitter turns into dark spots depending on the direction of the “pixel”. (I can’t believe I’m trying to create fireflies in Cycles…) :smiley:

The second lesser problem is that the material is very dependent of the color of the sky/environment. The whole material kinda takes the color of the sky. It can be fine… as long as the sky is blue.

The last glitch I must take care of is to add a scale factor to the whole thing. There is no problem with various objects of different sizes in a scene but the material needs to be scaled according to the scale of the scene. I encountered the problem when I appended the material from my test file into the scene with the gift boxes. The snow looked like a uniform bluish material because the boxes are like huge buildings compared to the snowman.

(Before I forget…) The node tree. Still quite simple.


Opinions, critics, ideas… (I’ll share the blend file when I’ll be more satisfied by the result or tired of working on it.) :wink:

looks very good.

Your last line made me chuckle…

:smiley: “Simple” refers to the shaders I used. For the rest, well, you might say “Ouch!” when you receive a full grown tree in the face but, when you watch it grow (or build it), it’s immediately much less impressive.

Blender artists have a node tree for christmas!

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Originally Posted by place57http://blenderartists.org/design/baorg2012dark/images/buttons/viewpost-right.pngYour last line made me chuckle…

(opps dunno how to do a quote here)

chuckle I fell off my chair!!
just out of interest(sure I cant do the math) do you start with maths an work to nodes
or use an artists eye to tweak nodes??

Oooh that thing would come in handy :slight_smile:
hope to see it soon on Blendswap^^

I’m a tree farmer. My trees grow organically. :eyebrowlift: I start with a base color and tweak visually. (I kiss the feet of the guy who came with the idea of the real time rendering in a viewport .) The math just pop in my head when I need it. Any way, I don’t use any complicate formulas of optical science, I don’t know any. And if my inner scientist bails on me, I pop a can of Google Aid. :wink:

That’s the plan. Tomorrow or, more likely, tuesday because of the time difference in between Pittsburgh and me. (Some Internet Sorcerer told me that BlendSwap should be located in this area.) Right now, I’m too busy having fun fixing the mess spit out by the boolean modifier. :confused:

about the scale
what size of plane did you use for the snow ?

have to get it going right i get black snow but ahve to review it a little !LOL

thanks

In the scene with the snowman, the ground plan is only 5x5 units… While it’s 40x40 for the packets scene. (The node tree shows the numbers for that scale.) And in both cases, the ground plane extends just a little bit around the camera view.

I think that explains the problem with the scale… and how much fun I’m gonna have to insert a multiplier in the tree (while I didn’t respect any factor actually). :confused:

only way i see would be to make a script to calculate the scale factor !

thanks

I tested it is just a great big thanks

Could you try a Glare node for the glitter?

I could… if you tell me how to extract some random procedural pixels from a very grainy material made of shades of white. :smiley:

Seriously, I don’t think it’s possible. Besides, I have very mixed feelings toward the idea of a material depending on compositing.

:eek: I can’t believe this thread is 2 months old! Time flies!

would the light path node help with the “glitter”
ps I’m not that great in cycles so if its a silly idea kick me :wink:

I tried to use glossy for the glitter. That was my very first idea. A bad one. With glossy, the glitter totally depends on the lighting. A simple white diffuse was just dull. With glossy or diffuse, the glitter disappears either in the shadow, in the light, with the distance, because of the angle of view, etc, etc. Using emission isn’t perfect and it makes the rendering time hit the roof. Maybe it’s an artistic point of view but it’s what feels the most right to me, altho I can’t make really bright and blinding spots as I would like.

Catch! :wink:



Big snowball seen from front and back. (200 samples only.)

And of course, you couldn’t find my file on BlendSwap. Not released yet. I was still working on it. The node tree is tidied up, the file is loaded in Blender for another snapshot, I’m gonna do it… NOW! Any way, it’s looks like I can’t find a factor to scale everything. People will have to fiddle a bit…

That’s it, you can grab the file from BlendSwap: http://www.blendswap.com/blends/materials/snow-material-for-cycles/

Next! I just got a really crazy idea for a material… :smiley:

Too much! Altho it should work in theory, your snow looks like sand. Snow is made of water which has a tendency to produce round shapes and not that many sharp angles… :smiley:

hey there must be around 20 different type of snow
also depends on temperature i mean it’s not something simple

keep it coming
variety is the spiece of snow

happy cycles