RBD Packed Object in dops: Overiding the s@bullet_georep possible?

[Alex Lombardi]

I want to define individual pack primitive's geometry representation in sops with an attribwrangle and string value.

If you dive inside the rbdpackedobject there is a bulletdata node with a dropdown list (Parameter is bullet_georep). I can edit the expression on the dropdownlist and put a simple string token "convexhull" or "concave" and it updates fine.

 

I just cant seem to pass a string attribute I created to override the expression. @mystringvalue shows up in the geometry's attributes, but i cant wire my attribute in to override the string token. Am i missing something super simple here or is this the wrong place to override it?

 

Cheers

 

 

 

 

[cwhite]

There currently isn't a way to specify the geometry representation per packed primitive (all of the supported point attributes are listed at http://www.sidefx.com/docs/houdini13.0/nodes/dop/rbdpackedobject). A workaround would be to split the convex and concave pieces between two different RBD Packed Objects with the geometry representation parameter set accordingly.

[Alex Lombardi]

Thanks Cameron,

yeah I didn't see any attributes relevant on the list that's why i went in and started exploring

damn...thought i was close  

[Skybar]

This is the first result on google, so just wanted to tell that it is possible since H15: https://www.sidefx.com/docs/houdini/news/15/dynamics.html

I also haven't found a better way, but if you change the bullet_georep during the simulation you need to reset the "id" attribute for it to work properly. For example I'm emitting stuff as "convexhull", and when they reach a certain threshold I switch them to "box". At the same time as I set bullet_georep to "box", I also set id = -1 (only once, when the change happens) to make it force update. This will of course create a new set of ids on our packed prims (they will change), so be careful if you use it to identify a specific packed prim later on - either set up a new static index in another attribute or use name.

[Nicholas Ralabate]

you saved my bacon, was using boxes for the heavy impact of metal pieces but right before it was due noticed the box collider was leaving too much padding, so right after impact switched to convex hull... thanks!