Scatter By Density

[JJ FX]

Hi, 

Im confused. Why my scatter by density does not scatter. 

Invalid point density attribute specified. It must be a numeric atrribute

Isoofset, VDB to polygons, fluidsource. They all give invalid point density attrib

 

 

ScatterByDensity.hiplc

[eetu]

If you want to spatially vary your scattering by an attribute, you need to have an attribute of that name present on the geometry you are scattering on. (You don't have one).

 

If you just want to scatter uniformly, toggle the attribute off.

 

[JJ FX]

Yeah thats what I dont understand. Why isooffset does not create density attrib? Neither does vdb from polygons (but it does create density, just scatter SOP does not see it).

 

No I dont want scattter uniformly, I want scatter by density.

 

Look at the example file, there is density

ScatterByDensity_VDBfromPolys.hiplc

Edited May 3, 2017 by JJ FX

[eetu]

You are mixing up two kinds of "density". There is density of a volume, meaning the value attached to each voxel of the volume. (the volume may or may not be named "density")

The density attribute is an explicit attribute you can create, which Scatter SOP then takes into account when scattering points. (the attribute may or may not be named "density")

 

And yes, Scatter SOP scatters into a volume taking account the density of the voxels (in the first sense above), see the attached.

ScatterByDensitye.hiplc

[JJ FX]

Hm... Okey I think I get it now. Thank you!