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View Full Version : "Noise" node: usage?



jeric_synergy
08-05-2012, 10:21 AM
I'm attempting to use the Noise node to add a little "Noisy Channel" channel modifier-type noise to an instance offset, which is a Scaler input.

Using InputSpy (so happy it exists), connecting the yellow Noise output to the green Scalar input , I'm not seeing any variation in values, indeed, I'm only seeing zero.

The dox lean heavily on the idea that the Noise node is use to perturb Textures, and the yellow output is a bit mysterious. If I just want a noisy output, is this the node to use?


Thanks!

jeric_synergy
08-05-2012, 11:27 AM
I abandoned the Noise node in favor of Turbulent Noise, from which I at least could get an output. This was immediately more successful in that at least the Offset got perturbed, but the unexpected thing was:

(see jpeg)
the instance, ummm, 'foundation' or 'emitter' object is animated. The noise effect appeared animated, but only as long as the emitter was in rotation: when it became static, the noise became static, as if World Coordinates was checked on the Turbulent Noise node control panel (it was not).

Why is this so? Why is the noise acting like World Coordinates is turned on?

RebelHill
08-05-2012, 12:19 PM
The node you're referring to is a function [(f)x], and the output they give is functional, which is to say that it drives something which uses a function in its generation... such as textures.

All that idea of what they are aside, basically the principal use they'll have is modifying the gradient of procedural textures... like a colour correction curve.

And as for your second noise attempt, it becomes static because the texture is in the local space of the instance generator object... moving or rotating that object takes the texture with it. Were world co-ords on then you'd see no movement/animation of the textures effect irrespective of what the generator obejct was doing.

jeric_synergy
08-05-2012, 12:39 PM
And as for your second noise attempt, it becomes static because the texture is in the local space of the instance generator object... moving or rotating that object takes the texture with it.

We may be experiencing nomenclature issues here, as what you typed there seems self-contradictory to me. That is not the case: moving or rotating the i.g.object seems to move the object thru the noise field - in other words the problem is the texture is NOT stuck to the object. Sticking to the object is what I'm desiring, but not getting.

Were world co-ords on then you'd see no movement/animation of the textures effect irrespective of what the generator obejct was doing.
World co-ords both on and off had the same effect.

The setup is GimbalNull>Emmitting Plane. The gimbalNull is banking (because the plane is tilted 90 on P and can't be banked). The banking is the only keyframed animation. The Instancer is applied to the plane. I expected the noise field to be in the local space of the Instancer, so any displacement would be static relative to the plane, but that is not the case: the instances move around as if the noise field had World Coordinates enabled. Once the gimbalNull stops banking, the displacement stops varying.

I'd prefer the displacement be static in relation to the plane.