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Re: Instance Geo on particles

Posted: Thu Feb 06, 2020 6:19 pm
by juanjgon
In the scenes .zip file in the other post you have the "008-instancingCdColor.hipnc" that is an example using instances, not Octane sphere particles.

Thanks,
-Juanjo

Re: Instance Geo on particles

Posted: Thu Feb 06, 2020 6:50 pm
by efxlab
Strange, I tried the exemple with instance attribute, the instanced sphere render black. Maybe there is a missing setup, no particle color checheck ? or Octane Cd attribute actived ?

I tried too on my exemple too, no way.

DO you think its possible use too the obj Instance?

thx

Re: Instance Geo on particles

Posted: Thu Feb 06, 2020 8:35 pm
by efxlab
ok it working, Iam dumass artist, My octane setup was different, I followed exactely your project with the right spm path.
Thanks for your patience
efxlab wrote:I have just tested on houdini obj Instance, in my instance I created Cd attribute on points scatter/grid, I assigned to instance the Texture/ppm image through a octane network shop. No color render. In your url you dont use a Instance example but a built-in octane sphere scattering. Any recommendation about the setup ?

Re: Instance Geo on particles

Posted: Thu Feb 06, 2020 9:00 pm
by efxlab
work great now on obj instance. A last thing again, can I use a 4th custom parameters through alpha data ?
I tried to add @alpha data in point with in material a NT_TEX_INSTANCE_COLOR instance with alpha4k_map.ppm file, no success, any idea to use it ?

thanks

Re: Instance Geo on particles

Posted: Mon Feb 10, 2020 3:22 pm
by juanjgon
Hmm, nope, sorry. The alpha can't be handled using this workflow. I'm not sure if this is going to be possible without the proper support for instances point attributes, but I'll check it out.

Thanks,
-Juanjo

Re: Instance Geo on particles

Posted: Mon Feb 10, 2020 4:35 pm
by efxlab
ola. ok thanks.

For now I can color instances with Octane gradient or random color. I can use RGB color attribute for drive 3 users attributes (with an OSL separate channel node). Octane is amazing:)

Re: Instance Geo on particles

Posted: Thu Feb 13, 2020 2:01 pm
by juanjgon
efxlab wrote:work great now on obj instance. A last thing again, can I use a 4th custom parameters through alpha data ?
I tried to add @alpha data in point with in material a NT_TEX_INSTANCE_COLOR instance with alpha4k_map.ppm file, no success, any idea to use it ?

thanks
The next Octane 2020.1 plugin build will support the @alpha float point attribute inside the instances packed RGBA values ;)

Thanks,
-Juanjo

Re: Instance Geo on particles

Posted: Thu Feb 13, 2020 5:26 pm
by efxlab
amazing Juanjo,
I see in the snapshot that the right alpha name is @alpha and not @Alpha, I was not sure about the syntax, great that its come soon in houdini.

Re: Instance Geo on particles

Posted: Wed Sep 28, 2022 7:40 pm
by thanulee
Bumping up this thread as I am trying to replace a vellum grain sim with custom objects while maintaining also the custom float attributes that I have to colorise the grains.

My sim is around 10m grains and when i try copy to points (even if not visible in viewport and packed prims) H lags a lot and Octane cannot even start.

Is there a solution for this? I was expecting under particles besides "render as spheres" to be able to have a "geometry" option where we point to various sop paths. I tried also octane scatter its not working on grains and in any type of points for that matter unless a polygonal surface.

Please let me know what is possible.

Re: Instance Geo on particles

Posted: Thu Sep 29, 2022 3:13 pm
by mirocreative
thanulee wrote:Bumping up this thread as I am trying to replace a vellum grain sim with custom objects while maintaining also the custom float attributes that I have to colorise the grains.

My sim is around 10m grains and when i try copy to points (even if not visible in viewport and packed prims) H lags a lot and Octane cannot even start.

Is there a solution for this? I was expecting under particles besides "render as spheres" to be able to have a "geometry" option where we point to various sop paths. I tried also octane scatter its not working on grains and in any type of points for that matter unless a polygonal surface.

Please let me know what is possible.
Did you try using an instance object with the points inside? Works for me 90% of the time.