[Custom Build] Blender Fracture Modifier

(Tedri Mark) #1661

Does anyone have any information on how to use constraints with the fake cloth? I’m trying to use it to make a spiderweb attached to a door and doorframe which stretches and then tears.

(drgci) #1662

Can we have the latest buildbot builds with fracture modifier?

(Tedri Mark) #1663

Still looking for this demo file - need to figure out how the constraints work in order to stretch cloth:

I’ve searched in here


but can’t find anything with that setup

(scorpion81) #1664

since I dont have this file any more, I rebuilt 2 similar setups. They can be found in that googledrive folder under stretch_cloth_constraints1.blend and stretch_cloth_constraints2.blend.

The first file is just a fake cloth (in this case created by the addon with 1 click) and connected to the cylinders just via regular constraints (select both cylinders and make fake cloth plane active, then Physics -> Connect -> Location : Selected (in the operator). I did this 5 times in a row and distributed the resulting constraint empties a bit across the cylinders by hand. You can connect fractured and non fractured rigidbodies this way. Works too if both constraint partners are fractured.

The second file uses “external constraints” and those work only between fractured constraint partners. Easiest setup is by selecting multiple FM objects and in the FM Helper addon, under “Automations” press “Connect” (not “Combine”). What this automation does is that it will set up a helper object which is animated / ghost, and has an FM on it. This FM references a group of other FM objects to be connected by constraints (on shard-by-shard basis). It uses the “Sub Object group” field and the “Constraints only” checkbox under “Advanced Fracture”

Note : the connections in the 2nd file might look more exact / accurate, but this setup is more crash prone. If your door and door frame is not fractured and you dont mind a small number of empties to be managed, you can use the regular constraints, else try the external ones.

(scorpion81) #1665

Hi, do you mean the latest master merged into FM ? or rather a 2.8 version even ? There are no released builds for both yet, but if you dont mind to compile them, the sources are here:

https://gitlab.com/scorpion81/blender (for “fracture_modifier_final”, this is master from end of july 2018 or so merged into FM) and…
https://git.blender.org/gitweb/gitweb.cgi/blender.git/shortlog/refs/heads/temp-fracture-modifier-2.8 for a 2.8 version, BUT Note: the 2.8 version is VERY buggy, unstable and not feature complete yet compared to FM 2.7x

(Tedri Mark) #1666

Ah brilliant, much appreciated I’ll check them out, thanks!

(Tedri Mark) #1667

Any way to avoid the UVs getting distorted when applying the fake cloth sim?

(scorpion81) #1668

Ah, d’oh … the Fake cloth operator (in the addon) additionally adds a corrective smooth modifier after fm, which causes the distortions. Was thinking (without UV) it might look nicer, but indeed, it distorts the UV. You can remove this modifier after the FM. A catmull clark subsurf mod will also “smooth” the cloth a bit, but does not distort the UV as far as i could see. Tested with cycles render / material view.

(wolfie138) #1669

Really interested in this, but

  • when i go to the wiki blender page you advise, it’s got no text and the user is unknown,
  • the df-vfx link on your gitlab page just gives me a host page
  • the kaikostack link above is blocked by ESET saying it has HTML/ScrinjectB.Trojan.
  • unless i’m doing something wrong, none of the google drive links seem to do anything.

not really confidence-inspiring.

(RLGUY) #1670

Looks like the link on GitLab is out of date. The current Fracture Modifier site is located here: http://blenderphysics.com/fracturemodifier/

Combined a fracture simulation with a FLIP fluids simulation:

(wolfie138) #1671

you obviously have better google skills than me! much obliged for the link.

(IIBit) #1672

I have a pre fractured object ( exported out of Houdini ) and everything works, except when I set my trigger as ghost. Then I get nothing. What am I missing?

(scorpion81) #1673

did you fracture the object in houdini and exported the shards ?
Or did you fracture the exported object in blender ? In the first case you should have a set of separate objects, in the second case one object with a fracture modifier on it. But both ways should work if either each shard object or the FM object is set to Animated (so it only moves with animations) and Triggered (to be affected by triggers) . Each object to be triggered needs to have the “Triggered” setting enabled too.
You also can join the shards into 1 object and use the FM with NO pointsources enabled. It will then re-use the existing shards and operate on them.
Ah, and that ghost trigger setting was not working some time ago, i fixed it then. But which release do you use ? graphicall.org/1148 ? or from blenderphysics.com or kaikostack.com/fracture or even self-compiled ? or googledrive ? Unfortunately their release date differs. I think the graphicall release and the kaikostack release from August 11th are the newest, the latest commit is from September 9th, 2018. Those are only a few (relevant) commits, though.

(IIBit) #1674

Hey Scorpion81,

I did export the shards out of Houdini as an OBJ with groups ( each shard is a group ). I don’t know which version of the fracture modifier I’m currently at, But I will update :slight_smile:

Thanks for the information.

EDIT: I’m using the Blender Fracture Modifier build from 8-10-2017 ( hash 57d70b3 )
EDIT EDIT: Downloaded the latest build. Everything works great.

(drgci) #1675

Will the fracture modifier merged in to the official blender 2.8?

(<== Lost? Click Me) #1676

Uh, put it in finished works and or feature row. Looks legit.

(JTA) #1677

Scroll back up to August 5th to see the answer to that question.
Fracture ON!

(JTA) #1678

Hey Scorpion81 King found a cool new tutorial that has FM in it by Gabriel Aguiar Prod. Excellent techniques on preparing a hollow object. A must watch!
Fracture ON!

Unity 2018 - Game VFX - Shatter / Destroy / Explode Objects Tutorial

(vihreä) #1679

I got the latest version, but i just can’t get the inner smoke, dust and dubris stuff work. I think I’ve tried everything. Also Im not getting the purpose of the helper objects :frowning: Please enlighten me.

Thank you in advance!

I found out that I had to make the floor as brush! Now I got to the next level of testing this. Its awesome aand I bet its just gonna get more awesome!

(scorpion81) #1680

Hi :slight_smile:
The particle systems or the vertices of helper objects can be used to generate more dense pointclouds in certain areas, in order to generate smaller shards there on the FM object.
E.g. if you have the default cube and use a smaller cube as helper and position it in one of the corners of the default cube, you will notice that if you either add a particle system, put the helper into a group and assign the group to the FM object and fracture (or use the addon which automates most of those steps) that in this area you will have more and smaller shards. This is helpful to make shards of varied size, so they dont look all uniformly sized.