Delete points based on Ray Cast values ?

[CinnamonMetal]

How can I delete points where there is not a float point attribute.  For example, I created a float point attribute on the geometry and where that attribute doesn't exist on the geometry the points \ particles are deleted; or better yet, using the raysop, ray cast particles only where a float point attribute exists on the geometry when the particles go outside of this attribute on the geometry, the particles are deleted ?

[Masoud]

Hi "Christopher",
Do you mean that you want to delete a point if it doesn't contain an attribute?

Something like this:

https://www.sidefx.com/docs/houdini/vex/attrib_suite#detail

or this? :

https://www.sidefx.com/docs/houdini/vex/functions/haspointattrib.html

Edited April 25, 2020 by Masoud

[CinnamonMetal]

Another way to put it is this; How can I create an attribute for the Ray SOP which will project those points which the attribute has applied to the target geometry based on an attribute on the geometry ? 

haspointattrib() may be what I need for the geometry. 

Edited April 25, 2020 by CinnamonMetal

[anim]

it's impossibe to have attribute only on part of the geometry (unless it's nested inside of packed prim), it's either on all elements of the geometry or none

do you mean you want to delete points which hit parts of geometry where the attribute value is 0.0? In that case just import attributes from hits and delete or do something based on that value

ray_get_hit_attrib.hip

[CinnamonMetal]

I'm importing the hit attribute and that seems to do the Job.

Edited April 26, 2020 by CinnamonMetal

[CinnamonMetal]

I figured it out

Edited April 27, 2020 by CinnamonMetal