Hmm..just fiddling with lightwave objects, If I would make a simple box that is cloned with the array tool so that I end up with a wall of bricks.
the boxes are all in the same layer and they are not connected to each other, they were then exported in object format.

I would like to simply make that wall a rigid body and that works fine, but they of course fall down and react as a single body.
whats the easy or proper way to make them react as single pieces.

I tried RBD fractured object, but I haven´t figured that one out for standard things in houdini anyway.

phamarus

The Connectivity then Partition SOPs will do what you want. I think there is an example on one of them. Then RBD Fractured object should do the trick!

Cheers,

Peter B

Thanks.
Hmm..that didn´t get me any clue thou how to apply it thou..The Connectivity then Partition SOPs..

The only topics I can find in the help files are about glue where it´s mentioned
about connectivity and following that also partition.
I guess I have to learn about expressions for this, I hoped it would be a little easier to setup thou, It´s very easy to setup in lightwave just making the object a hardfx and from there tell it to be one piece or treat it as parts either
when falling or only after falling when colliding with other objects.

Lighwave hasn´t that of a good self collisions thou, so I wanted to try it out in houdini.

Phamarus

I think there are a number of examples of that issue in Help but anyway, this is an example with Connectivity and Partition SOPs. Very common stuff.

Cheers,
sy.

Thanks symek for the example, will study that.
I had an error message when loading it but it seems to be working okay anyway.
Im a little surprised that the calculation actually seemed slower in houdini,
I exported the array object out and used hardfx on that with gravity and a collision plane and it calculated smother in lightwave, perhaps some setting in houdini maybe.

Im anxious to learn houdini anyway cause of the powerful procedural aproach, some things I hate and some things I love, but that goes for Lightwave to and other programs, just ironic that the thing that sucks in one program does it so well in the other.

Houdini Dynamic Engine is generally slow. Slow but stable, predictable, and physically accurate. This has a pros and cons of course. I had a bad luck to fight last week with other dynamic engine and after the first impression of fresh and lighting speed - so to speak - we couldn't get any decent results from that. Fast first try, and nightmare of unresolvable problems. Try really hard simulation and you'll see the diffrence.

On the over hand there are some fields on which general slowness and unresponsiveness really makes troubles - this is cloth sims for example.

Anyway, don't lose your faith - Houdini is like a tank - slower but everywhere

cheers,
sy.

PS The parameters you should be aware of in respect of performance: Collisions Passes, Contact Passes, Subcontract Passes, Minimum and Maximum Substeps - all of them on RBD Solver. Their default values are high for simply sims, and low for any advance