Blender: How to make realistic excrement of any objects (seriously)


New Addon:

I made a Blender add-on “Crack It” for the process in the tutorial.
Using the add-on, you can make excrement, tree, rock, or etc.crackit_present_title1_1_credit1


Tutorial: Blender: “Crack It” Addon Basic Tutorial – Gappy Facets.



Excrement is very interesting compound. It is basically mud, but forms ensemble of a few clots. What’s more, the little balls are squeezed to merge into a long, fluid-like shape.

I think you can make excrement by two ways: bottom-up approach or top-down approach.


Bottom-up approach with particle:

The bottom-up is what I tried and I’m not satisfied with the result  in previous posts a few months ago. The way uses particle and molecular add-on.
The pros is that you can make animation the particle simulation. The cons is that since it can’t make clots, it looks like a mud as below.



Top-down approach with cell fracture:

Now I tried to make the organic material by making crack on a object. Of course, crack itself is not enough. You must make condensed rocks from them.
The result is below.


How to make excrement with cell fracture:

1.Cell fracture add-on setting:
Set own verts and noise=0.05 in particle source. Recursion=2. Clump recursion=0, big in recursive shatter.

The all fracture objects should be selected and joined into one object by “object > join” in the lower menu bar. The result is like blow.

fracture3_shit1_cubesurfer12. Apply decimate modifier to simplify the mesh. Ratio=0.4,

3. In edit mode, selecting all vertices, apply multi extrude add-on. To extrude it to outer a bit, set scale=0.1, repeat=1.


4. Also in edit mode, apply MiraTools‘ noise to make clots. Noise=0.8.

5. Add subdivision surface modifier, render=2.

The result is below. The material is EA_dirt_G of Meta s Massive Cycles Matlib v15 Alpha | Blend Swap, fine-tuned to more green.
Compering to bottom-up particle approach, this mesh has balls merging together.



Cases of other objects:

You can do it for any objects.
The blow is scaled icosphere.



The below is an object along with curve.



Deer comes.



Even Godzilla.



The uneven mesh can be interpreted as other things, when you change the material.

High heat metal.



Fried chicken.



The kitchen setting is Kitchenware Scene | Blend Swap made by timbazi.
The deer object is from Deer – 3d model – .obj.
The Godzilla object is from Godzilla – 3d model – .obj, .dae.

Series Navigation<< Blender: “Crack It” Addon WIkiBlender “Crack It” Addon: How to customize cracking point >>
  1. Hi,
    very funny tutorial, giving interesting elements on cell fracture plugin.
    Could you go more indepth on the “joining” process after the cell fracture step (what should be selected and ho to select ?


    • Hi Boid, I always join the fraction into one object, I mean I select all the objects and execute “object > join”.
      I updated the sentence of the blog: ‘The all fracture objects should be selected and joined into one object by “object > join” in the lower menu bar.’

      I must admit that the process has many steps and difficult to follow.
      So I plan to make an add-on to make cracked objects so that users can make excrement, wood, and other organic stuffs easily. The name would be “crack-it” or “excrement-it”.

    • Hi Bold. After 6 months from the comment, I made a new blender addon “Crack It” to automate the process I describe in the post.
      If you are interested in making excrement, tree, rock, or other cracked objects, use the addon.

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