Hello there, 
for the project I am currently working on, I have to destroy a wooden pavillon. The .abc file I exported from blender 2.93LTS seems fine until I convert it to polygons. I think there may be a problem with face orientation but I am not sure. When I then append an RBD Material Fracture, some some parts of the model have these weird artifacts, which I assume are the cutting geo used by the fracture node. (see screenshots)
Apparently the files are too big to attach to this post so I uploaded the needed files to wetransfer. The .zip contains a .hip file demonstrating the problem, a .blend file containing the model, the .abc I exported and also a .fbx version I exported. 
https://we.tl/t-lvg7J7cXQf [we.tl]
Help would be very much appreciated, thanks in advance <3
                    
					
                    
                        
                            Weird Material Fracture Artifacts
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 - FunkyPants
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                         - robsdesign
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                        Hi, I had a quick look at this and found the following;
- You have some reversed normals.
- The fracture seems to work better if you have quads instead of triangles.
I've attached a hip file which doesn't fix it completely but points in the right direction;
- You can correct the normals on the reversed geometries by doing it in Blender or by using a Reverse SOP in Houdini. (The latter can probably be done procedurally)
- If you have quads in Blender, try to export as quads. (if not, you can try a dissolve sop)
Note: The base of the model still has a broken area caused by the fracture. However, if you delete everything apart from the base and apply a fracture, it works. This suggests there are still issues with the mesh. (Hence this is not a complete fix)
Rob
					
                    
                        
                            
                        
                    
					
						
					
                    
                    
                - You have some reversed normals.
- The fracture seems to work better if you have quads instead of triangles.
I've attached a hip file which doesn't fix it completely but points in the right direction;
- You can correct the normals on the reversed geometries by doing it in Blender or by using a Reverse SOP in Houdini. (The latter can probably be done procedurally)
- If you have quads in Blender, try to export as quads. (if not, you can try a dissolve sop)
Note: The base of the model still has a broken area caused by the fracture. However, if you delete everything apart from the base and apply a fracture, it works. This suggests there are still issues with the mesh. (Hence this is not a complete fix)
Rob
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 - FunkyPants
 - Member
 - 4 posts
 - Joined: July 2018
 - Offline
 
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