Jump to content
kikohs

VDB combine sphere + polyextrude custom surface attribute.

Recommended Posts

Hello everyone,

I have just started using Houdini but I'm stuck following a VDB tutorial from Entagma with my own object.

Basically, I have a kind of barchart created using a custom attribute H on the primitives of a grid via a polyextrude node. I can't transform it properly into a VDB regardless of the voxel size if I use fog or distance. Yet it works if I add a custom surface attribute on the VDB. Now that I have my barchart volume, I cannot VDB combine it with other volumes. I tried specifying the group and play with all parameters but I have this error:

 

5bdc87b18635d_ScreenShot2018-11-02at18_22_51.png.6d5ea0f86b0707f04a7faafd5e990758.png

 

I have linked the project to make it clearer.

Thank you very much for your help.

 

grid.hipnc

Share this post


Link to post
Share on other sites

Hey Kikohs,

I'm not able to upload a file at the moment, but hopefully I can help anyways!

First thing: your polyextrude is currently only extruding, but not creating a closed object. Make sure "Output Back" on the Extrusion tab is checked to have it create a closed object. VDBfrompolygons requires a closed object to correctly generate a VDB.

Next, turn the Distance VDB back on in the vdbfrompolygons.

Finally, in your vdbcombine clear the group fields as it will use the surface volume by default (which I believe is what you desire).

Let me know if you have any other questions!

  • Like 1

Share this post


Link to post
Share on other sites

Hey Coltonmil,

I didn't know about the polyextrude.

Thank you very much for your answer. It works like a charm!

Cheers

 

 

Share this post


Link to post
Share on other sites

Create an account or sign in to comment

You need to be a member in order to leave a comment

Create an account

Sign up for a new account in our community. It's easy!

Register a new account

Sign in

Already have an account? Sign in here.

Sign In Now

×