Glass Geometry & RBD Connected Face Node with RBD Tools in Houdini

[@mattbrunner1208]

Very effective tut! A small addendum to this workflow: if you are mixing multiple streams of geometry (say a concrete wall with a glass window), and you don't want to see cracks in either before an impact, you need to split out the geometry output from the rbdbulletsolver, using a Split node for each stream. Then you can use the RBD Disconnected Faces on each geometry stream separately. Lastly you can merge the geometry back together for your render.

[@bubblepins]

Very good idea! But usually the concrete material wouldn't be translucent so you wouldn't see the cracks either way, but I thought you're idea was really interesting, because this will come in handy for other translucent materials! Maybe jello or pixie-glass or cracking marbles. Nice Idea!

[@greccovarella9711]

You just saved me on a huge project. Thank you so much!!! You're an incredible teacher. Keep it up!

[@bubblepins]

Thanks!!

[@nathanmeier8780]

This node has to work on unpacked geometry and it's looking for a primitive group called "inside" (that's the default prim group for inner faces created by the rbdmaterialfracture). If you're fracturing your geo through methods outside of the default houdini SOPs call the inner prim groups whatever you want but before you pipe the geo into the rbdconnectedface node make sure you change that group name to "inside".

[@flux2787]

legend

[@flux2787]

Thank you so much! Was looking for the rbdconnectedfaces node thank you for covering this :)

[@bubblepins]

Thanks for watching! I had a lot of fun with this video. The RBD COnnected Face nodes make it so satisfying to render out transparent materials like glass!

[@jbach]

This is excellent! One aspect of glass shatter I was hoping you would cover though is proper setting of constraints when you have say a window in a frame and some object shatters the window but leaves glass shards stuck to the frame.

[@bubblepins]

You can use the red configure node and create a bounding box to make the middle pieces active and the inactive ones will become the shards. I have video on this but it's on destroying metal but uses this bounding box to hold it in the frame kzbin.info/www/bejne/nqjSaKehr5trkJosi=8s4oSO-SCGCpsOYC&t=1761 Hope this helps!

[@TheWillvoss]

Thanks for taking the time to make these. So great.

[@bubblepins]

You're welcome!!

[@MrManet]

Thanks, exactly what I've been looking for

[@bubblepins]

Thanks for watching!

[@JZ5U]

Very cool, thanks for sharing. I was just looking at what the sliders in rbd glass fracture did, but learnt a lot more.

[@bubblepins]

Thanks for watching!

[@troopxl666]

Very good explanations, thanks!

[@bubblepins]

Thanks!

[@jono8326]

Thanks for the tut again! How do I prevent the cracks from frame one? I want it to fracture at a certain frame only. Many thanks!

[@bubblepins]

You can use the RBD Material Fracture node has this constraints tab where it'll automatically create the constraints for you, that should hold the object together until something impacts it. But due to the complexity of setting up constraints and tweaking the values, it wasn't covered in this video. Hope that helps!

[@jono8326]

@@bubblepins thnak you for the reply!

[@viktorofobos]

Hi bubble pins - great lesson I have a question, how Connected Face in Houdini 17.5.173? Version 18 differs from version 17 thanks

[@bubblepins]

Yeah there were a lot of updates done in Houdini 18 to the RBD Tools' nodes. I don't think the Connected Face & Disconnected Face nodes are available in 17.5, not totally sure, but SideFX did a lot of updates to the RBD Tools in 18. I actually never used Connected faces until H18.

[@viktorofobos]

understand I will find out) thanks again

[@tolgabostancifx]

Thank you so much !!

[@bubblepins]

Thanks for watching!

[@kyozhan7172]

hello,I have a plobem about "rbddisconnectedfaces", the inside surface are rendering out before fracture.can you help check my file,plz

[@TheWillvoss]

would this work with the old dop network / making your own constraints? Or DOP imports? prim attributes -- but just not getting it to work. Tried unpacking/disconnect as well.

[@bubblepins]

I just did a quick test and it seems like its working. You need to connect your constratins into the the middle input of the RBD Connected Faces node. So if you're doing it manually (if you need tips on this, I have a different video on Creating Constraints Manually). kzbin.info/www/bejne/nH7JpWSkhrGgmpo You will have two outputs then, first output is the fractured geometry, which should be coming out of the voronoi node or whatever you use to fracture it. Then you may use a Connected Adjacent Pieces node that will manually create lines between each fractured piece, which will be your constraints geometry, this goes into that middle input of the RBD Connected Faces node. So all this is done BEFORE the dopnet. After the dopnet, you need to use the RBD Disconnected Faces node and choose "Delete" connected faces. Then you'll get the same effect as shown in this video using the old DOPNET way. Hope that helps!

[@none53]

why fracture per piece dont work, when we add our own (add) input ?

[@bubblepins]

I did a quick check, it does work with my own voronoi fracturing fed into the RBD Material Fracture node with "Fracture per piece" enabled. Make sure you drop down something like an assemble node with "Create Name Attribute" option enabled to ensure you have an unique name for each piece before it get fed into Material Fracture. It relies on the name to figure out which is which piece. Hope that helps!

[@none53]

@@bubblepins thanks for the help, btw i am getting problems in my fbx files , i want to texture and render glass in 3dsmax, so what should i do to get rid of normals , i applied normals nothing worked , i used the same technique u did in this video , by connecting and disconnecting fractures and aslo used assemble and create packed geo, but nothing worked for me , what should i do more for normals , its like flickering all over in 3ds max when i applied glass mat, to it .

[@bubblepins]

@@none53 Have you unpacked the geometry before exporting it out? I'm not sure if it's actually necessary, because I suspect the ROP nodes unpacks the geometry for us before exporting. But I usually unpack it myself to be safe. Double check if the interior faces are actually be removed from the RBD Disconnect node so we can narrow down the issue if it's a simulation issue or an export issue.

[@none53]

@@bubblepins hi i get rid of my normal flickering , by just adding normal node to it, but rbd connected and disconnected fracture didnt work in 3ds max , when i import bcz it shows no mesh in my viewport and assemble node showed the same, so now the problem is how to pack it like the same , like when it collides then it shows the cracks and all

[@bubblepins]

@@none53 I don't have 3ds max, but I did a quick test with Houdini to Blender: twitter.com/BubblePins/status/1384518717564932097?s=20 I didn't use RBD Configure, which is the node that does the packing. I'm curios though, maybe just maybe, if 3ds max may have different options to import the Alembic file. I wonder if it's importing as mesh cache and not deleting the interior faces? Because the older versions of Blender had a similar issue, but was fixed in the later versions of Blender.

[@JuanRomero-wz7mx]

can i install redshift in the non comercial edition?

[@bubblepins]

Yeah, I used the Redshift Trial for awhile before I bought the license, the only downside is there's a watermark and the User Agreement says you cannot use it for commercial use. But other than that, I think there is no limitation in terms of feature.

[@yashgangurde1655]

No. I tried to do the same. You can't use third party renderers in the Non Commercial Edition.

[@user-xjcltmddn]

If i use the rbd configure node, the rbd disconnected faces node does not work. What should I do?

[@bubblepins]

oh .. this happened to me at the beginning too. THere are a couple of things you need to check: You need to check if you selected "Delete COnnected" in the rbd disconnected node. And if you used rbd configure node inside the chain then you need to unpack the geometry before the rbd disconnected node. Try these two things and let me know how it goes.

[@user-xjcltmddn]

@@bubblepins I unpacked behind the solver node and used the disconnect node but failed. You're not telling me to unpack before using configure, right? I found faceid and primist in primitive attribute when unpacked after solver, but failed in render view.

[@bubblepins]

@@user-xjcltmddn Unpack it after the solver but before the disconnect node. And it still fails? hmmmm... now you got my head scratching. I suggested to unpack the geometry because the rbd configure node packs the geometry and I recently found out that in order to use the rbd disconnect node, you need to unpack it back to access the primdist & faceid data. Is the faceid and primdist attributes available before you unpack the geometry and is it available on the disconnect node? Can you describe the issue with more details, do you get an error in the render view?

[@user-xjcltmddn]

@@bubblepins If i proceed in the order of rbd connected places->rbdbullet solver->rbd disconnected places, the glass is not broken in render. However, if i proceed in the order of rbd connected places->rbd configuration->rbdbullet solver->rbd disconnected places, the glass is broken from the first frame at render time. So, as you said, I did the rbdconfigure->unpack->bullet solver->disconnect, but the glass was broken from the first frame.

[@bubblepins]

@@user-xjcltmddn rbdconfigure->bullet solver-> ** unpack ** ->disconnect Put the unpack after unpack after the solver but before the disconnect. Remember to choose DELETE mode in the rbd disconnect node. If this works, you should not see the interior faces, so if you render it as a glass material, see through, it will look like it's not broken, because there isn't interior faces, the disconnect node deletes them I hope this works!

[@pinkmoon5332]

great tutorials. Really goes at the basics. Much appreciated. But PLZ get a better recording setup. You're all mumbley!

[@bubblepins]

THat might just be my voice, lol I find that my voice is quite low pitch.

[@pinkmoon5332]

@@bubblepins hahaha understood. 'tis fine. I just think you'd benefit from a nice crisp recording that would capture hi's and mid-ranges that are missing from your recordings. Just my option of course. I only listen to audio through speakers. I might benefit from putting on some headphones. Perhaps it's already there. Cheers!

[@bubblepins]

@@pinkmoon5332 the funny thing is, I find my voice is much more clear in the morning! I never thought I would be looking into what drinks to clear up my voice LOL but I think I'll do just that