AlNoise textures for arnold

arnold_noise_textures

If you been following Grant Warwick’s Mastering Vray series, you certainly reconsider procedural texturing. But 3ds Max users have some powerful noise shaders/textures, like the Bercon noise, which as far as I know it’s not available for Maya. In this post we are going to explore some 3rd party noise textures, part of the alShaders library, that will give you more flexibility than the standard noise/fractal textures.

alCellNoise

alcellnoise maya arnold

This node is a common cellular noise texture as you see in the image above with the default attributes. The first thing you have to do with 3D noise textures is to set the right scale/frequency, this will obviously depend on your scene size. You should also set the “space” mode, either to world or object. In world mode, if you have several objects they will “share the 3D texture space”, whereas in object mode, each one will have a different look, as if they had an individual 3D placement node.

alcellnoise maya arnold 2

Playing with the attributes you can achieve different looks, in the image above you see we have that worley noise look, that can be really useful for overall slight bumps, and also roughness/glossiness maps. In this example, I just increased the octaves and lacunarity to get more noise detail, and setting the F1 to 1 and leave the others at 0.

Just as a side note, be careful with the randomness and shape attributes, they will easily create some weird results, specially breaking the tileablility of the texture. You should keep the shape around 2 and the randomness around 1, if you expect predictable results.

alcellnoise maya arnold 3

Some scratches created again with the alCellNoise node, this time we play with the “unpredictable” shape attribute to get a busy result, and then using the feature weights attributes we can mask out the effect.

alcellnoise maya arnold 4

Another example where you have a more “dusty” result. Here I increased the lacunarity, reduced the randomness and shape attributes, and changed the F values again.

alFractal

alFractal maya arnold 1

The alFractal is a fractal noise texture that any 3D package has in their procedural textures library. You should be already familiar with the octaves and lacunarity attributes, they behave the same in all noise textures. The time attribute is just a texture offset control. The gain and distortion should be used with caution, they will let you create interesting patterns, but they are very sensitive, increasing it too much will make the pattern too busy. Of course you can always end up with an “happy accident”.

alFractal maya arnold 2

Here we use the vector attributes to stretch the texture in a particular direction. Then increasing the gain attribute to mask/contrast the effect, along with the turbulent and ridged attributes. There is no much I can explain here, it’s a matter of playing with the attributes to get familiar with the node limitations.

In some of the examples I am using the remapHsv node in between the node and the shader to play with the levels, to get the desired balance of black and white areas.

alFractal maya arnold 3

Just using the turbulent and ridged attributes, but this time using a lot of distortion which is ok because we end up masking most of the effect with the ridge offset.

alFractal maya arnold 4

Here we take advantage again of the vector attribute to scale out the effect in a desired direction, and using an high lacunarity along with the right ammount of Octaves to get more noisy details.

cg generalist course therenderblog

Combining textures

You will obviously get much better patterns by combining different noise textures and even mapping the attributes with other procedural nodes.

alnoise maya arnold shader 1

The image above is the result of a alCellNoise combined with the last alFractal example I have shown in the previous section. The textures are mixed with a layered texture, experimenting with the different blending modes, in this case multiplying the alFractal over the alCellNoise.

alnoise maya arnold shader 2

Here we use the alCellNoise to create the displacement effect, creating the stone sharp shapes with lower Octaves and Lacunarity, and the feature weights to space them away from each other. We also use another alCellNoise to mask out part of the displacement effect to get some variation and avoid a busy repetitive pattern.

We also use the same alFractal node used to mask out the displacement effect to create some splatter pattern in the diffuse color.

Some test shaders created using only procedural patterns :

alnoise maya arnold shader 3
alnoise maya arnold shader 4
alnoise maya arnold shader 5
alnoise maya arnold shader 6

We only scratched the surface of he possibilities with noise textures. Mapping attributes with other noise textures, layering them, adjusting their contrast, masking parts of the effect and other techniques will give you even more control. Let me know if you would like more posts about this procedural approach, and if you like our articles you will probably enjoy our course, the CG Generalist Course.

Thanks for reading.

  • Wizix

    Really, really interesting subject. For sure, you can develop and make more article on that suject, there a lot of workflow to explore!

  • http://www.envmanu.com manuel huertas marchena

    Very useful information! thanks for sharing!

  • http://boyangeorgiev.tumblr.com/ Boyan Georgiev

    Hello, thank you for sharing this. It seems to be very useful. I tried doing it myself but I couldn’t figure out the settings. Do you think you could make a tutorial on this?