[Custom Build] Blender Fracture Modifier

(JTA) #1581

Kaik strikes again! Love the airbag demo, lol…it put quite a big smile on my face! Fracture ON!

(dafassi) #1582

Hey guys. As im working on the new project-page blenderphysics.com i would love to add some user-reviews.
Please rate and comment the Fracture Modifier (1-5 stars) in a short text and send it with your full name, a picture of you and your job (hobby, freelancer, animator, etc…) to info[AT]blenderphysics[DOT]com

THANK YOU :slight_smile:

(jensverwiebe) #1583

BlenderFractureModifier 2.79b GNU/Linux is available now according to the official release scheme:


Cheers … Jens

(Rickietee10) #1584

I’m sorry if this is a repeat question, but I couldn’t search the 80 pages in the thread for the answer.
I’m having a lot of problems with blender crashing when I try and simulate stuff. If I start a simulation off, it’s fine, I test the physics then add constraints, test, then fiddle with the constraints, test… so on. Until I’m happy with them. Then for unknown reasons, I go back to the start frame, blender crashes.

I can’t fathom this out, I’m pushing 32gb ram, on windows 10, i7 4790k @4.00ghz with 3 graphics cards, one display card gtx730 I think and 2 render cards, gtx 1080ti’s (I’m a freelancer, I promise It’s not Overkill).

Does anyone know why it would keep crashing, for what seem to be simple physics (50-100 shards max)?

(English is not my native language) #1585

Thanks Jens!

(scorpion81) #1586

Hmm can you provide a simple test blend, which does reproducibly crash ? Alternatively you could write down the steps you performed until the crash happens. But in general, its wise to change parameters and execute fracture (when necessary, eg. changing fracture algorithm or shard count) always on the startframe, and restart the simulation from there.

(JGwinner) #1587


This modifier is a lot of fun.

I am having a problem going through the tutorials :frowning: If I create a cube, fracture it, create a plane (ground) underneath (animated dynamic object), then check “Enable Deactivation” and “Start Deactivated” the cube ALWAYS explodes (falls / fractures) before the sphere hits it.

I tried moving my constructed ground plane away, and that seems to help a little, but of course all of the particles fall forever when the ball does hit the wall.

So for some reason the ground plane ‘starts’ the wall moving, even though it’s supposed to be deactivated. I didn’t see any of the rigid body defaults being changed in the video tutorial. Was there something I missed??

“Drop to floor” would be handy.

I know this is a stupid question, as I don’t know THAT much about physics yet (I usually do this in ReactVR/Unity), but I’ve looked at the tutorial closely, and other than the default world having a ground plane pre-loaded, I don’t see what I’m doing wrong.

Did some default in Blender change? I’m using 2.79a.

Sorry for the dumb question,

== John ==

(Remade) #1588

inflation of airbag- is it using cloth modifier or something specific to fracture build?

(scorpion81) #1589

Hi :slight_smile:

The cube needs to have the checkboxes “Animated” and “Triggered” activated, and the sphere needs to have the checkbox “Trigger” activated. This way the sphere will activate only the shards it touches (or which are very close). You can optionally enable “Ghost” on the sphere so it only activates, but does not collide. Trigger, Triggered, and Ghost are FM-build specific options, but work with normal rigidbodies in the FM build, too.

Same for the wall. Make it Animated Triggered, and the sphere triggered. The ground plane may have contact then at the bottom of the wall, but it doesnt matter if it is no trigger. Only Triggers can activate Triggered objects.

If you additionally use particles from blenders particle system, the ground plane needs a collision modifier. But this is the same like in official builds.

Start Deactivated and Enable Deactivation can be enabled additionally, but because this doesnt work as expected with activating only certain shards, I added the trigger / triggered feature quite early in the development process.

Hope it helps you :slight_smile:

(JGwinner) #1590

Ah. That helps!

I did get a weird thing where a block of ice over some letters doesn’t continue to fracture. The wall also ‘spiders’ before the ball gets close, but I’ll experiment with thresholds and the like. The block looks weird, as there’s a huge hole in the middle and the rest of the ice won’t “fall” but I’ll go through the rest of the tutorials. For the concrete wall this is just right, of course.

This obviously isn’t a full finite element modeler, but for an artistic plugin this is fantastic - so fast. Thank you guys so much.

I have stuff to play with now :slight_smile:

== John ==

(JGwinner) #1591

Also - has anyone used this to “bake” polygons for real time / game rendering?

Some posts are missing?
(jonnytracker) #1592

you can start your own branch of release… As a VFX artist, I need this tools and Blender should not regard it less important. Maybe I should go back to 3Dsmax. while blender is being busy special and different

(JTA) #1593

Playing with Gottfried Hoffman’s caustics demo file for Appleseed/Blenderseed render engine addon combo. Used the Fracture Modifier branch to break up the glass and run Blenderseed. Render time of 2:27:21 on a i7/3+GHz 2 cores Linux guest/Windows host vbox.

See blenderdiplom.com for the source file and great article. See appleseedhq.net for the awesome render engine and blender addon. Fracture Modifier animations work great too! Congrats to the Appleseed team on an awesome new release!

Fracture ON!

(jonnytracker) #1594

need help with this tutorial https://www.youtube.com/watch?v=Qt4fjzFqB5U&t=134s

the tree is so solid it can support 10k tons of concrete box

stuck at assign vertex group to 1 and click assign, also my tree is a mess

(steveernst117) #1595

I’ve got some questions about the whole Multipass thing that’s apparently in the works. My assumption from watching the demo videos is that it enables you to destroy a chunk of an object, in effect weakening it, and then watch it fall in a physically correct manner, is that right? I was just thinking about this today watching some bts of ‘the return of the king’ when the tower crumbles at the end, and I thought, ‘hmm, can I do this with the fracture modifier build?’ Then I tried it and it turns out you can’t…haha. Unless I just don’t know enough about how to control fractures. Anyway, that’d be awesome.

(sus_unn) #1596

Yeah sometimes I can’t understand core devs too, because of things like this.

(Gilles Charbonneau) #1597

A quick Blender Fracture Modifier test, I am trying to prevent the pieces from dancing around, I tried the Untrigger option, but it seems to have no effect!


(scorpion81) #1598

Hello, I tried to reconstruct a tree example but took a different approach with triggering and cluster groups.
Please see the blend, it also contains some explanations for parameters which are different from the default values. Note for sake of simplicity, i also did omit the leaves.

(scorpion81) #1599

Hmm, multipass basically works with the “Fracture Animated Mesh Settings” Panel. For example, if you have a scaled fractured cube ( a thick plane like a ground plane) and put another subdivided Plane on the same origin, and make it move, e.g. with a pinned cloth sim (pinned at each corner), you can set the FM object to kinematic and say “Use Animated Mesh”, specify the “cloth” plane as object to bind to, and hit “Bind”, and then if you let the sim run, the shards near the moving cloth plane should follow that plane’s movement (Optionally also check Use Rotation and rebind). That is the basic principle.
In multipass you bind smaller objects which have a lot of tiny / lightweight shards to heavier objects, like fractured windows to a concrete structure of a highrise. This way, if the heavier structure collapses, it should take nearby bound shards with it, accordingly. You can set those bound shards to triggered too, and if a trigger hits them, they should be “free” again, and controlled by physics again. Note, this is kinda experimental still, so if in doubt (and if having a blend file, lol), post the link here so i can try to take a look at it :slight_smile:

(scorpion81) #1600

You could try to make the Ground thicker (extrude) , recenter its origin and make it a box or convexhull, then enable Collision margin checkbox and set its value to 0 (or slightly higher, if it works better). This firstly should prevent long skinny shapes to penetrate it (probably you have a plane with mesh shape as ground atm)

Then set the ground as Stop Trigger / Untrigger, and important, the object which shall be stopped must be Triggered (but not Animated, since it shall fall). Note that only shards touching the ground will be stopped, if there are some shards piling up on others they will keep moving. And you can manipulate the stopping velocities too, its just the deactivation Linear / angular velocity which is taken into account here (if below those values, stop). You dont need to use Enable Deactivation, even if the velocities are greyed out they effect the stop trigger mechanism. For example, higher stopping velocities should let objects stop earlier. E.g below 4.000 stops earlier that below 0.400, obviously.