Hi everyone,
I am having issues using glue on imported objects, does anyone know what could be causing this. I am using scatter and voronoi to shatter the object, and that part seems to go fine, the sim runs fine with rbd shatter solver, but when I try to add glue to it, it still breaks into pieces even if set to -1.

This is the tutorial I was following
http://www.youtube.com/watch?v=K5ekmyXnBbs [youtube.com]
and I can replicate this, the problem happens when I try to use imported obj.

Any suggestions would be greatly appreciated.

I got this sorted out, but now I have another problem. I have searched the net for answer but cant find one.

I have an object that has more than one primitive in it (text) , but when I hit it with an static object they all act as one. There has to be a better way to do this than to set up each letter separately. I have looked at the point rbd, but dont see an option for selecting more than one mesh.

:?: :?: :?: HELLLLP

You can use the RBD Fractured Object to create multiple RBD objects from your source geometry based on the ‘name’ primitive attribute or based on primitive groups.

Thanks for the reply, I did eventually find something on the web about this, and am working on it now. Just to make sure I am on the right track, are you referring to the connectivity and partition nodes to create groups?

Yes, you can use those, but the simplest solution is to use the Assemble SOP (which internally uses those nodes) - the default settings should likely give you what you need.

Also, if you use the RBD Fractured Object shelf tool and your geometry doesn't already have a name attribute or groups, it will put down an Assemble SOP for you.

Ok, I got it to work with the shelf shatter and rbd fracture, but I was trying to use rbd fracture glue, and I am still having issues. Also I was trying to use a cookie node to only fracture the top half of the text. That part seems to be ok. I use a box with mountain and cookie before I go into the iso offset. This works as I want it. Its the gluing that has been driving me crazy all day!

What I am tying to do is have a static object, that only breaks off the top of the text but leaves the rest in place.


Thanks again for your time… much appreciated!

If you don't want a piece to move at all, there are a couple options you could try:

- Use the Active Value DOP to make a specific object passive.
- Import the piece separately as a static object.

“- Import the piece separately as a static object.”

Yep, I am in the process of doing this now. I will also look at the other option you mentioned. The documentation for Houdini is the best I have seen, the problem is that if you dont know what to look for its not much help. I am slowly getting through all the help files.

I actually got this to work how I wanted using the glue object on the shatered mesh and on the ground collision. Very pleased with the result. I do have one issue that I still can't work out, but its not a big deal. If I break the object into too small of pieces I get some very small fragments that are not effected by the glue. I am assuming there is settiing that deals with resolution of sim/ glue but I can't seem to figure out what setting it is. Like I said, its not a big deal… these are very small pieces, smaller than I need, but I would like to know the setting that can fix this for future reference.

Assuming that you're using the Glue Network Constraint, the glue network is generated by a Glue Pieces node. For that node, the Points per Area and Search Radius parameters can be tweaked to control how nearby objects are detected and glued together.

Yes, glue network constraint. Points per Area and Search Radius worked. I did see those settings before and I thought that I had already tried that, but it must have been earlier in the process when I was still dealing with other issues.

Thanks so much for your help. I did learn a bunch about these tools in the process.