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Hey,

I spent a while prepping and adding to a model house for a destruction project but I'm having a lot of trouble gluing everything together.

I can get the components of the house to glue together no problem (e.g. the windows, the walls, the bricks etc). But what I really want to learn is how to glue each of the fractured components to eachother.

What I mean is that my house just falls apart, the bricks dont stay attached to the wall, the glass windows don't stay in their frames the roof shingles dont stay on the roof.  I'm really hitting a wall here (no pun intended).

Can anyone lend me a hand in figuring out how to approach this?

 

The picture is my destruction model.  Each component (roof, walls, etc) has its own constraint network but they arent glued to eachother so when I sim the pieces just pop off.
 

house.png

house_sim_fail.png

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Hi, I have an idea..

First you want to make sure your fractures have a unique name attribute prefix

Voronoi Fracture - Attributes - Name Prefix parameter.

You should then be able to merge the centroids of your different parts and follow standard constraint workflow.

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3 minutes ago, Yon Anadeyo said:

Hi, I have an idea..

First you want to make sure your fractures have a unique name attribute prefix

Voronoi Fracture - Attributes - Name Prefix parameter.

You should then be able to merge the centroids of your different parts and follow standard constraint workflow.

Ok, thanks for replying!

What I found out since I posted was that I had a bunch of constraint networks in my DOP network and each one had a glue cornel with each layer of the house (messy workflow I know, I think I know how to clean it up though) 

and what I noticed is that they all worked but the one constraint network with the gluecornel with the full constraint (every piece glued in one connect adjacent pieces node) wasn't doing anything.  So I tried it in reverse and got rid of all the previous networks and just kept the constraint network that connected every piece and it worked.
 

I'll try your suggestion and reply with my results but before I do, I understand everything you said except for the part about merging the centroids, what do you mean by that?

 

full constraint.png

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at the simplest level constraints are just connected points with different name attributes. 

in my file I change the name attribute so that there are only 2 unique names that connect adj pieces can create connections between.

Then replace the name attribute to what it was initially so bullet knows which packed pieces to constrain in dops.

There is a bullet masterclass out there that is great if you haven't already checked it out

constraints.hip

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Hi,

I am destroying a building too, and I realized that the easiest way to trouble shoot these problems is to break it down into smaller problems. Some points to consider:

-How are you fracturing your geometry? If you are using Voronoi Fracture, then it will setup the right attributes for you, specifically "name" primitive attribute. If you want to use one mesh as one piece (e.g. an entire wall that you know it won't fall), then you could use Name node and type in a unique name for that mesh. 

-Do you Pack your geometry using Assemble node? If it's a heavy simulation (and I think your sim is heavy as I can see), then you should pack it using Assemble node. Using Packed geometry and RBD Packed object is very handy when it comes to flagging some pieces as passive or active (e.g. the base of your house should be passive as it won't take part in simulation except for collision)

-As per constraints, you can build constraints network for each "section" of your house OR you can build an entire one. BTW, building a constraint network is very easy (I don't know its details, I just copy and past a punch of nodes created by the tool shelf and connect them to other section of my mesh AND I add a constraint network in DOP simulation). This is an optimization thing, also you could make some constraints weak and some strong, it's your call ...

-As per falling parts, it could be either : (a) they are not glued to any object so they fall due to gravity (check your constraint network visualization), or (b) there are no passive objects that they glued to make them stationary, or (c) your constraint bonds are too weak and they still fall due to gravity (just increase the strength of your constraints in the constraint network)

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On ‎10‎/‎21‎/‎2016 at 3:36 PM, JP Shep said:

Ok, thanks for replying!

What I found out since I posted was that I had a bunch of constraint networks in my DOP network and each one had a glue cornel with each layer of the house (messy workflow I know, I think I know how to clean it up though) 

and what I noticed is that they all worked but the one constraint network with the gluecornel with the full constraint (every piece glued in one connect adjacent pieces node) wasn't doing anything.  So I tried it in reverse and got rid of all the previous networks and just kept the constraint network that connected every piece and it worked.
 

I'll try your suggestion and reply with my results but before I do, I understand everything you said except for the part about merging the centroids, what do you mean by that?

 

full constraint.png

I mean simply merge your two parts before feeding connect adjacent pieces , making sure they have unique name attributes

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