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luidox
Does anyone use angle controls to displace noises in an attribute VOP?

For example, I want to displace on a surface area of 65° relative to the Y axis.

More example, take a tessellated cube and rotate from its natural default position. As the faces angle, the set noise on the certain degree begins to reveal.

i'e been told Dot Product does this but i need some hand holding examples.

this image shows my goal. smooth noise to heavy noise at a different angle
Konstantin Magnus
You would compare a vector pointing upwards against the surface normals using a dot product.
luidox
thats really nice. any chance of seeing this in a vop solution? im not really a fan of vex. im an old school artist and as such we artist don't think that way

also i guess im kinda looking for something with more of a numerical literal control. like

turbnoise shows at angles 0-30 degrees
unifiedstatic shows at angles 31-60
worley shows at angles 61-90

so on
luidox
bump
mestela
Like this?
luidox
mestela im trying to utilize angle only with the ability to do this with an infinite amount of noise. that way im not confined by typical vector direction but angle.
mestela
You can convert that 1 -> 0 -> -1 value that a dot product returns into a 0 90 180 degree value if you're so inclined.
luidox
mestela
You can convert that 1 -> 0 -> -1 value that a dot product returns into a 0 90 180 degree value if you're so inclined.

im not too sure which value your saying should be changed. in the dot product i tried messing with the numbers and got less than desirable results.

im also not sure how to add more noises. say maybe something like 50. i would never need that much but it would be nice to have the freedom
luidox
could this be done in a volume vop? i tried copy past and rehook but nothin worked
Nicolas Longchamps
Yes, by using the SDF gradients.
Given an SDF, you can do a dot of a vector (up in your case, 0,1,0) with the gradient of the distance field.
luidox
i took the above and tinkered around.

you can see my botched attempt here. im trying to use dot products with trig math to assign angles to each noise. ideally instead of having it project like a 6 planer set up id like it to work based on numerical angle inputs. im shooting blanks here and in need of some guidance please

the gradient l like above is fine too
blackpixel
If you want numerical control as a mask, then just feed the angle with some offsets into 2 Fit Range VOPs and multiply them. Wrap the whole thing into an HDA and you should be good. You can also modify it to use another angle instead of thickness if you need something like 30°- 60°.



The example by Konstantin Magnus gives you much nicer ramp controls though and I'd argue that you could recreate that snow image with mestela's solution:
luidox
blackpixel
If you want numerical control as a mask, then just feed the angle with some offsets into 2 Fit Range VOPs and multiply them. Wrap the whole thing into an HDA and you should be good. You can also modify it to use another angle instead of thickness if you need something like 30°- 60°.
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The example by Konstantin Magnus gives you much nicer ramp controls though and I'd argue that you could recreate that snow image with mestela's solution:
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This has worked great. is there a way to get import point nodes to work with this?? i am not having much luck and getting alot of exploded verts as a result.
Aizatulin
If you want a variable number of different noises, you can use a multiparm list. Here is a vex approach, but quite similar to the

previous examples.
luidox
Aizatulin
If you want a variable number of different noises, you can use a multiparm list. Here is a vex approach, but quite similar to the

previous examples.

is there a way too have this sphere example work based on position rather than angle? im trying to position noise info on a set of stairs but i don't want to noise to touch every stair case. id like it to work its way up functionally rather than work on all similar angles.
Aizatulin
Instead of the angle you can use a float point attribute, which gives you more freedom. You can use the height, the angle, captured

attributes from another geometry or whatever you want. In my example the name of the attribute is “u”.
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