How to input an attribute in an HDA parameter?

[probiner]

Scene file attached with a example case(Normal Displacement)where the problem is presented in 3 columns:
left: Just HDA with single input value driving all points.
center: Attempt to use a random value attribute @foo to drive each point. Failing.
right: HDA exploded with @foo driving each point. Working as intended.

I inputing @foo and `point(0, "foo", @ptnum)` in the HDA parameter but it didn't work.

So what's the best way to set up HDA parameters to also be driven by a per point attribute?

Thanks



should look like this with the random value point attribute.

 

 

AttribDriveParameter.hiplc

Edited December 29, 2017 by probiner

[probiner]

Fixed scene file. Typed "Embeded" instead of "Embedded" in the HDA path >_>

[probiner]

I got some answers at sideFX forums and here I explain my questioning a bit more.
Basically: Is it possible to drive a single SOP float parameter with a geometry attribute? So far seems like the one way to go about it is to have an extra sting parameter to name the attribute... 

Cheers

Edited January 8, 2018 by probiner

[probiner]

Ok, here's the how I went about it to avoid burdening the UI. In a wrangle inside the Asset I check if the attribute exists with the same name as the parameter in the UI, and if not I create it with the UI value:

float attrib = ch(“attrib”) ; // UI value variable from a spare input in the wrangle SOP.

if(! hasprimattrib(0, “hda_attrib”)) f@hda_attrib = attrib ; // If the attribute doesn't exist, it's created and the UI value assigned to it.

or if I just need the variable:

float attrib = ch("attrib") ;

if( hasprimattrib(0, "hda_attrib")) attrib = prim(0, "hda_attrib", @primnum ) ;

Might not be very pretty to create/rename/copy attributes before the HDA, but since they share the UI parameter name it's straight forward enough, while allowing neat extra control.

Cheers

Edited January 22, 2018 by probiner