Cell Fracture and Materials/Textures from the Original Object

Greetings everyone,

First if this is not in the proper area, I apologize off the bat… Please point me to the proper area.
I did try to find information on the following question in the forum, but did not have any luck.

As for my question. I have been playing with Cell Fracture to shatter a textured mug. I have a total of 50 shards and the simulation works perfectly for my purposes but only for an “all one colour” object.

See here http://youtu.be/DfHm5sLJ08E

The problem I have is how do I assign the textures and materials from the original object to the multiple shards of the fractured objects. Any of the tutorials on the subject that I have found have the fractured object all one colour. And when I try to UV map the 50 new objects, well, they definitely do not conform to the original UV layout.

If someone could point me to a good tutorial on fracturing textured items or explain how I would get the original texture back on the fractured items, it would be appreciated.

Thanks

Pte Jack

You can have an outside material and an inside material. To leverage this BEFORE you fracture assign a new material to the object so it has two materials. Then, in the Cell Fracture dialog box, increase the Material Index from 0 to 1. Then all interior faces generated by the fracture will use your second material. I am not sure if UV mapping is supported by Cell fracture (i.e. labels/decals on a cup end up correctly mapped to shards).

In this image I chose white color for outside and charcoal color for inside.

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Thanks Atom, I have that already, the broken faces on the shards are set as you suggested and use the second material, it’s the outer materials that I want to retain (ie the labeling).

I tried to join all the individual objects together in a separate model and use the quick paint tool but because the fracture tool sets up edges to solve smoothing issues (I think the smallest shard had something like 28 doubles to removed when pulled the mug back together and the largest had 3 or 400 doubles or a heck of a lot more, I can’t remember), it didn’t work.

Is there an easy way to UV map the shards so that they all end up on the same uvMap and not overlap each other?

It seems to work for me. I imported an image using Images To Planes. Then I extruded the face up to make a cube. I subdivided it a couple of times and then ran the Cell Fracture on the mesh. The resulting shards did retain the UV mapping as the attached image shows.

Are you using more than one UV map?
Can you post your non-fractured BLEND file?

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Hmmm, Interesting… I can’t seem to reproduce your example. Maybe because you are using a cube/plane and I’m using this…???


This is what I am trying to break. The top is the mug whole and the UV, the right is my Fracture settings, then the bottom is the result showing one of the shards on the map. There is a separate Blender material for the edges of the breaks (as per Richards (Blender Cookie - https://www.youtube.com/watch?v=DEo_9AopfoQ) Using Cell Fracture Tutorial ) Maybe I missed something in the setting (like a keep uv setting or something???)

I’ve been sitting here for a few hours now remapping shards. I attempted to use the Texture tools Quick Edit function to repaint each shard of the mug after separating them out to one UM Map but found the result too fuzzy or too badly aligned across the shards as I patched it back together because of the ununiformed size of the shards on the map (which causes resolution issues on the model…)

I KNOW there has to be an easier way, but this is all new territory for me.

This actually shows all shards on the map…


I really appreciate your help with this, Atom.

Well, I got this to work, but in order to do so I had to remap every shard manually. There must be an easier way to do this, especially if people generate a huge number of shards or have complex models that they are fracturing…

Any ideas???

Thanks…

I just tried it again using a Cylinder instead of a cube this time. And it still worked fine for me. You are UV mapping your object before you fracture it…correct? The only setting I changed in the Cell Fracture dialog was to enable use Own Verts and turn off Own Particles.

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hmmm, Let me try that using your settings, because the fracture was performed on the UV’d material.

Thanks again Atom.

This has me totally miffed!!!

I can’t get the mug to retain it’s materials, but if I build a new object, cubed, sphere, make a new cup with subdivisions and solidify modifiers, assign an existing material and a shard material as mat2, fracture it into 2000 shards and it works perfectly, the objects retain the materials correctly…


(Don’t worry about how the materials appear, it was merely a test.)

But apply the same process to the mug, and I end up with the botched materials…

I’ve Killed the materials, brought the object into a new session and reassigned materials, I just don’t know.

I even modified the seams and unwrapped a new UV so that it was a more square and reapplied the materials. I still end up with garbage for materials through the whole model after the fracture.

Maybe it’s the model itself, the way I solidified or subdivided it, I just don’t know…

I’m going to remake it and try again.

Thanks Atom, now that I know it does works, I’ll close this thread off and start a new link if I continue to have problems…

Kindest regards…

Pte Jack