Scatter points on surface with falloff density near the edge

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Hi.
How i can scatter points on surface with falloff density near the edge?

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Hi,

you can use the xyzdist() function to measure the shortest distance from any point of the surface to the border. After this you can use a ramp for example to set the @density attribute, which can be used in the scatter node. Make sure that you have enough surface points (for scatter).
Edited by Aizatulin - July 8, 2019 13:24:28

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Maybe less efficient than Aizatulin's solution, but a code-less approach is to use a falloff node.
Have a look at the example file (play with the parms in the colored node to change the effect)

Also, a more exotic approach would be creating the density map in a cop network.
Import your shape with a geometry node and try to shrink and blur it with some filters.
I tried a bit, with no much luck, the shrink/expand cop node seems buggy.
It would interesting to see it implemented..

cheers

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Annyone know how to do this with volumes ?
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NicTanghe
Annyone know how to do this with volumes ?

If you have an SDF, you can use it to remap density using a ramp:

float density = fit ( @surface, ch("min"), ch("max"), 0, 1 );
@density = chramp("density", density);


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And do you have the SDF file? If so, in the case of volume, you can most simply use it for the next density mapping using the ramp. This is a proven solution that I have had the opportunity to use on more than one occasion.
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