new pieces of voronoifracture are getting disappeared in DOP

[Babak]

Hi guys,

my object is getting new points to make new pieces in Voronifracture, in SOP it is ok,

but in DOP new pieces are getting disappeared and RBD object doesn't work properly,

how can I keep my geometry data as the source in DOP ?

a smaple is attached,

thanks

RBD_Test.hipnc

Edited May 30, 2013 by Babak

[ehsan parizi]

your incoming geo is changing which is always a bad thing and even worse in this case! I don't know why you're changing your voronoi fracture but keep in mind that even though you're adding more points to the existing set of points, the result of the voronoi fracture is not breaking the already broken pieces, it creates new patterns and the new piece might have parts of 3 other pieces which doesn't make sense to DOPs.

Anyway, if you wanna have different levels or steps for breaking your object, there are better ways for it. But if for whatever reason you must have the current setup, then I don't think you can use it in DOPs!

[Babak]

thanks Ehsan,

actually my project is in some area while the animation is going on I want to break my geo procedural in certain points, not the whole geo, only small area, what can I do ?

thank you so much,

[ehsan parizi]

I'm not sure what exactly you mean, but if you wanna break you geo in certain parts only, just use a cookie or something like that, isolate that part, break it and merge it back with ther rest of your geo.

[JuriBryan]

Hi,

here is how I would solve the problem.

The example file shows a simple version of the solution you are looking for.

First you want to create the fracture with as many pieces as you want, then you create a centroid point for each piece and colour them.

After that you use the colour attribute as a activation value in DOPs, that allows you to only trigger the simulation on pieces that actually need to break.

If you say that you have moving geometry and you only want to break the ground, or what ever geometry you want to fracture, where you actually need pieces I would recommend using a attribute transfer for colours inside of a solver node. You want to transfer a colour(red) on the to be fractured geo(black), that way you have the geo coloured where ever you need it to fracture.

Then its a simple matter of a timeshift node set to the last frame of your sim, a scatter node that uses the Cd attribute as guide for the scattering and then you use those points to fracture the geo.

After that you use the method shown in the example file, but instead of a sphere you would use the animated geo to colour the points (quick tip: simply transfer the colours on the ground geo that you used to create the scatter points before the time shift, that way you have that calculation only ones in your overhead)

Now you can cache both the pre fractured geo and the points you use for activation out and just play with the look of your shot with out worrying about the over head.

Hope that helps you out a bit,

Juri

RBD_Test_Working.hipnc

[Babak]

thanks Juri, it was really helpful.