Brick wall: glue network strange behaviour

[gigafrax]

Hi everyone, first post here.

I'm starting to learn houdini and of course i need a lot of help since the documentation is quite poor...i hope you guys can give me some heads up.

My problem is basically the old brickwall destruction problem.

My goal is to destroy the wall having clusters of bricks, single bricks and brick shards. and of course i would like the clusters to break into smaller clusters or single brick on every subsequent impact and so on.

So far i managed to create a glue network which i delete gradually using a sphere with points from volume node, and painted clusters which are not deletable, so they should behave like subsets of the main glue network (breaking accordingly to their strength).

And here the odd behaviour happen...glue network bonds seems to reappear and stop the shards quite randomly.

anybody has any idea?

any help would be so much appreciated

also, some tips on how to paint different vaues of glue strength or how to procedurally set the glue strength based on distance between pieces would be a plus.

thanks so much in advance to anyone who replies this post

 

you can find attached a flipbook showing in red the glue network bonds that reappear

 

houdiniFlipbook.mov

[gigafrax]

somebody knws how can i attach the scene file? the file is rar since it would be too big and i got the follwing error when i try to upload : Error No file was selected for upload

 

for now you can download the scene file from wetransfer http://we.tl/Wwe9sQPcjB

[gigafrax]

i've just created a test scene to show the problem....i understand the original scene might look scary as it is so heavy...

testGlueNetwork.hipnc

Edited July 20, 2014 by gigafrax

[cwhite]

When you're cooking /obj/glue_sphere every frame, the DOP Import SOP keeps fetching the objects' geometry at their new positions, and the Connect Adjacent Pieces SOP recomputes a new glue network based on which pieces are currently near each other - that's why you sometimes see new glue bonds appear. I'd suggest placing a Timeshift SOP after the DOP Import SOP, with the Frame parameter set to 1. That will ensure that the constraint network isn't rebuilt from scratch on each frame.