Ice test

Hi all,

Matt Ebb has kindly reviewed the MLS patch, so it should make its way soon to the sim_physics branch.

As another example of the usefulness of MLS, here is a full volumetric ice test with MLS: hope you like it 🙂


Fig. 1 – Basic material (no volumetric)


Fig. 2 – volumetric with single light scattering): the volumetric lightning is localized


Fig. 3 – volumetric with multiple light scattering (come soon..). See how the light diffuses up to the ice edges.


Fig. 4 – Surface (Fig. 1) and volume lightning (Fig. 3) combined through basic node set-up


Fig. 5 – result


Fig. 6 – result with compositing tweakings

Ice test

23 thoughts on “Ice test

  1. Martin says:

    can anyone explain me, how i can add color to my volumetrics. i am able to create voxeldata and to display their intensity so that I can see a light absorption effect. i have three other voxeldata files for the RGB channels. how do i have to configurate the materials that each voxel has a density and a color value as well?


  2. Ruddy says:

    Hi Martin.

    1) First, you have to deactivate the volumetric base material, otherwise it interacts too much and can hide the textures: in the volume panel, set absorption on 0.
    You also need a density different from zero for base material, except if you control it through a texture, as otherwise the volumetric stays transparent (no interaction without density)
    2) put whatever texture: to give a color by emission (eg: red cloud even without light), go to the Map To panel and select “Emit Col” and select the color either below the “stencil neg no rgb” buttons or through color bands in the texture panel.
    3) the problem is that the texture needs to know how much it emits:
    if you let the emit slider in the volume panel on 1 instead of zero for base material, your texture will emit according to this value and mix its color with those above the slider. If you want fine control, I suggest you to deactive the basic material emittance (Emit slider in volume panel), and to also control it through a texture. So, say you have set both absorption and emit on zero for the basic material, just select both “emit” and “emit col” in the Map To panel so that the texture modify both emittivity and emittivity color.
    4) important: the density scale slider in the volume panel is a multiplier for the texture values: for the dataset from Farsthary’s simulator, the original values are pretty low (nearly invisible) so you need to put at least 10-100 to see the smoke

    To conclude, we have to think as if it was real material:
    – no density -> no interaction -> invisible
    – no emittivity -> nothing to see
    Once this two values are non null, just play with Emit Col and Absorb Col in Map To

    Hope this will help


  3. Ruddy says:


    1) put the density scale between 10-100 and density,absorption,and emittance on 0
    2) use the smoke dataset for the Density chanel in Map To
    3) use the red data set for the Absorp Col in Map To and select the red color
    …repeat this for the green and blue dataset..

    tell me if it works


  4. Marty says:

    I could wait! And after some trials I got it! Thank you so much, that helped me a lot! My main error was the background color (which was white in my case) so that I couldn’t see any Smoke color. But now everything works perfectly! 🙂


Leave a Reply

Fill in your details below or click an icon to log in: Logo

You are commenting using your account. Log Out /  Change )

Google photo

You are commenting using your Google account. Log Out /  Change )

Twitter picture

You are commenting using your Twitter account. Log Out /  Change )

Facebook photo

You are commenting using your Facebook account. Log Out /  Change )

Connecting to %s

This site uses Akismet to reduce spam. Learn how your comment data is processed.