[Custom Build] Blender Fracture Modifier

Amazing, glad I could help in some way! Made two more buildings meanwhile:

I’m not sure how to get the BCB constraint-weakening bomb to work, do I need to trigger it or something? Can’t figure it out. Also, is it possible to resume the simulation after I halted it, and to return the shards to their original size, purely visually, for aesthetic purposes. I noticed in your videos that you don’t have those gaps between panels. And one other thing - what renderer did you use for the Christchurch video? Looks very nice and quick to process. Thanks!


Nice buildings and simulations, you must have been quite busy making them. :slight_smile:

For the Detonator functionality you just need an empty object with the name defined as in the BCB settings in your scene. Scale it to the size of the area you want to weaken and place it where it should act at the building. Leave the Advanced Detonator unchecked to have a basic gradient-like weakening from the beginning.

If you want to use Advanced Detonator you need to simulate the entire propagation of the pressure wave in advance which makes it a bit more complex to control. I have committed another example file for this new feature to the repo:


The gaps are the result of the Rescale Factor setting which is 0.95 by default. It is useful to have these gaps for simulation to avoid intersections on deforming structures. I usually leave them in for simulation and revert them afterwards using a trick with a negative smooth modifier, but this only works well for clean box-like elements. Of course you can also change the Rescale Factor to 1.0 if accuracy is of less importance to you.

Progressive Weakening is another trigger feature independent from the Detonator, but this only works if no FM is used. It will weaken the entire structure with a defined factor per frame until collapse begins. You can try it with a value of 0.98 or so, after a while of weakening the structure will start to fail at their weakest points.

I’m using OpenGL viewport rendering for most of my simulations because it saves a lot of time, with some experience you can accomplish quite nice images even with old-school methods.

I will share a video of yours in my community tab if you don’t mind. Keep it up. :+1:

I really appreciate the share, thank you very much! Simulation is priority #1 for me, I was just wondering if it was also possible to make it more aesthetic as a bonus. I’ll try to use that trick, thanks.
I have tried using the detonator according to the manual but I guess I need to either place it before Building with FM or not use FM at all. I’ll also play more with OpenGL, I must have missed its settings panel - never knew it can be adjusted with shadows and outlines.

Regarding the OpenGL rendering, you need to switch the render engine to either Blender Render or Blender Game, then you can get shadows for spot or sun lamps when in material viewport shading mode. The disadvantage is that you cannot use Cycles materials anymore, you’ll have to use the classic material interface instead. It’s very old and obsolete functionality but still works for me.

Having said that, if you want to use a more recent Blender version and even Eevee to render your simulations then you can do this too by exporting your simulation result using Alembic, .mdd, or .pc2 point-cache formats.

I have added support for Progressive Weakening to work with the FM now, if you want to try it:


But I have to correct my earlier statement, the weakening value is inverted, so a good value to start with would be 0.02 rather than 0.98. :slight_smile:

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That answers why I came home very disappointed after I put a factor of 2 on an extremely slow simulation and left for work :smiley:

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Hy Kai Kostack. i tried the bullet constraint builder in 2.92 and i can’t find it where it is supposed to be 3dview/toolshelf/create tab.

The BCB is not yet ported over to support Blender 2.8/9, it still requires 2.79, preferably with Fracture Modifier. http://kaikostack.com/fracture

It’ll take some time to have it in Blender 2.9, so don’t wait for it.

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Hello, someone has already tried to port:

that is a 2.8 port for bashi’s bullet constraints tool. The BCB from Kai is totally different.

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oh, sorry then! :slight_smile:

I have completed a fun little project! Simulating an obviously terrible structure :stuck_out_tongue:


Wonderful! I really enjoyed this video, especially the BCB “promotional” part. :grimacing:

We are totally lacking video tutorials on the software, but your small introduction provided a good idea of what the software can do. :+1:

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