Points Attribute transfer Dilemma - point id not keeping it's value

[chishbak]

Hello Guys.

I got stuck here in a middle of an project and i can't find a solution.

My problem is : I have a grid  of points , and an animated point running over the surface of the grid.  My "running" point have an attribute that is transferd ( via attrib transfer SOP inside anSolver)  to the grid points by an proximity radius.

then I use the transfered attribute to isolate only the grid points that are tuched by the "running"point. But the @ptnum of the remaining points is changing. And i need the @ptnum to  grow in the order detection ( @ptnum 1, 2, 3, 4, 5 etc)

why is that happening

 

to understand better I've attached the scene file

 

ptnum_chaos.hip

Edited December 9, 2017 by chishbak

[3dome]

i dont understand your problem. the id's stay the same just fine. have a look at geometry spreadsheet. 

also both deletes work fine

Edited December 9, 2017 by 3dome

[chishbak]

My problem is that my points  after delete, are changin their point id  instead of being fix. If you show point numbers in viewport and then grab the timeslider, you can see for example der point 4  change it's position to point 5.  But i guess I solve it with an custom attribute id. ( i@id = @ptnum in an wrangle right after solver)

[3dome]

you already have an id attrib. you are creating it just before the solver
don't care about the ptnum Houdini is displaying in the viewport. It does change of course that is why you have the id attrib.
Just like with a particle sim where particles die and new ones get born they constantly change their ptnum in viewport but id (in spreadhsheet) stays the same

and no, setting id to ptnum after the solver wont help at all

Edited December 10, 2017 by 3dome