modify data with bullet

[toadstorm]

Hello again,

I'm trying to do a controlled destruction with the Bullet solver. I have a glue network set up so that I can have pieces break off and eventually split into smaller pieces. The problem is that the destruction in this case isn't forced by an actual impact... I want the pieces to just drift off. I was hoping to use a Modify Data DOP to somehow fool the pieces into thinking they've suffered an impact, but I can't seem to make it work. I was editing the "glueimpulse" value in the Position data for each piece... I know this works for the RBD solver, but nothing is happening in Bullet. The glue weight is zero, except for the cluster glue weight (which is -1).

Is there some other way to convince the chunks to break apart without an impact, but have the clusters stay together initially until I break those links manually in the glue network? I just don't want to have to surgically break off each large chunk in the glue network and then start breaking those down into smaller chunks completely by hand.

[cwhite]

The 'glueimpulse' value is used for the old-style RBD glue (along with the 'glueobject' field). For a glue network, the 'impact' primitive attribute on the glue network's geometry stores the impact values. If the impact value exceeds the strength of the bond, the solver will break the glue.

You can also break glue bonds manually by deleting the corresponding primitives in the glue network geometry - this can be done in a SOP Solver, or by turning on the "Overwrite with SOP" flag on the Glue Network Constraint DOP.

[toadstorm]

For a glue network, the 'impact' primitive attribute on the glue network's geometry stores the impact values. If the impact value exceeds the strength of the bond, the solver will break the glue.

Perfect! That's exactly what I needed to know. Thanks!