3d_modeling:blender:clean_up_occipital_3d_scan

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3d_modeling:blender:clean_up_occipital_3d_scan [2020/04/07 06:53] – [Normals] formlab3d_modeling:blender:clean_up_occipital_3d_scan [2021/10/13 03:07] (current) – [Auto-fix holes] formlab
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 ====== Clean up a 3D scan made with the Occipital Structure scanner ====== ====== Clean up a 3D scan made with the Occipital Structure scanner ======
-The 3D files from the Structure scanner often have holes and unwanted geometry. After following this guide you'll get a watertight model that is ready for color-3D printing. A basic understanding of mesh manipulation in Blender is necessary. 
-We will use Blender, but here is a [[3d_modeling:meshmixer:clean_up_3d_scan|guide]] that describes this process for Meshmixer. 
  
 +The 3D files from the Structure scanner often have holes and unwanted geometry. After following this guide you'll get a watertight model that is ready for (colour) 3D printing. A basic understanding of mesh manipulation in Blender is necessary.
 +This guide uses Blender, but here is a [[3d_modeling:meshmixer:clean_up_3d_scan|guide]] that describes this process for Meshmixer.
  
-===== Setup the mesh ===== +===== Basic cleanup =====  
-  - Import the mesh.+==== Open the file ==== 
 +The structure scanner delivers the 3D object in 3 parts: 
 +  * ''Model.obj'' is the 3D object 
 +  * ''Model.jpg'' is the texture file 
 +  * ''Model.mtl'' is a file that links the object to the texture. 
 +{{:structure_3d_scanner:cleanup_files.jpg?nolink|}} 
 + 
 +You only have to open the ''.obj'' file. The program will find the other files on its own: 
 +  * ''File > Import > Wavefront (obj)''. Choose the ''.obj'' file 
 + 
 +==== Setup the mesh ====
   - Make the mesh active (yellow contour lines instead of orange) ''left mouse click''   - Make the mesh active (yellow contour lines instead of orange) ''left mouse click''
   - Right click on the mesh and select ''Set Origin > Geometry to origin''.   - Right click on the mesh and select ''Set Origin > Geometry to origin''.
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 {{:3d_modeling:blender:01_montage_-_arrows.jpg|}} {{:3d_modeling:blender:01_montage_-_arrows.jpg|}}
-===== Join fragments to a single mesh =====+==== Join fragments to a single mesh ====
 The scan data coming from the Occipital Structure sensor isn't yet joined in a single mesh. It consists of multiple sections that overlap on the edges. To test this, hover the cursor over the object and go to ''Select > Select Linked > Linked'' (Shortcut: ''l'') (lower caps L). This selects all vertices that are linked. As you can see, only a single section is selected. The scan data coming from the Occipital Structure sensor isn't yet joined in a single mesh. It consists of multiple sections that overlap on the edges. To test this, hover the cursor over the object and go to ''Select > Select Linked > Linked'' (Shortcut: ''l'') (lower caps L). This selects all vertices that are linked. As you can see, only a single section is selected.
  
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 {{:3d_modeling:blender:02_setup_mesh_-_collage_-_arrows.jpg|}} {{:3d_modeling:blender:02_setup_mesh_-_collage_-_arrows.jpg|}}
  
 +==== Auto-fix holes ====
  
-===== Delete unwanted geometry =====+  * To see if there are any holes in the mesh, go in Edit mode and go to ''Select > Select All by Trait > Non manifold''. This will select all vertexes on the edges of holes: \\ {{:3d_modeling:blender:remesh_non_manifold_edges.png?400|}} 
 +  * {{:3d_modeling:blender:remesh_settings.png?400|}}\\ Apply a remesh modifier to the object and tune the parameters until the object is defined properly:\\ {{:3d_modeling:blender:remesh_remeshed.png?400|}} 
 +  * Try selecting the non-manifold vertexes again. If there are still some selected, repeat the above process, or export the object to Meshmixer to remesh it there. 
 + 
 +The 3D print add-on for Blender is helpful in preparing your object for 3D printing: enable the add-on ''3D-Print Toolbox'' in the Blender preferences. 
 +==== Delete unwanted geometry ====
 Cut away unwanted parts, like the surface the model was standing on. Cut away unwanted parts, like the surface the model was standing on.
   - Add a cube. Scale and position so it overlaps with the unwanted geometry.   - Add a cube. Scale and position so it overlaps with the unwanted geometry.
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-===== Redistribute vertices =====+===== More advanced cleanup =====  
 + 
 +==== Redistribute vertices ====
 The 3D scanner generates a mesh with messy topology. There are areas with very large faces, and others where there are lots of vertices crammed together. This creates visible stress points in the mesh. The relax function moves the vertices away from densely populated areas in order to be more equally distributed. Having the mesh relaxed will prevent a series of problems later on. This will change the shape of the mesh a little bit though. The 3D scanner generates a mesh with messy topology. There are areas with very large faces, and others where there are lots of vertices crammed together. This creates visible stress points in the mesh. The relax function moves the vertices away from densely populated areas in order to be more equally distributed. Having the mesh relaxed will prevent a series of problems later on. This will change the shape of the mesh a little bit though.
  
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 {{:3d_modeling:blender:03_delete_geometry_-_relax.gif|}} {{:3d_modeling:blender:03_delete_geometry_-_relax.gif|}}
  
-===== Manually Fill Holes =====+==== Manually Fill Holes ====
  
-==== Tiny Holes ====+=== Tiny Holes ===
 Fill tiny holes by merging vertices together. This way the texture will stay visible. Fill tiny holes by merging vertices together. This way the texture will stay visible.
  
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-==== Medium Holes ====+=== Medium Holes ===
  
-=== Clean up the edge ===+== Clean up the edge ==
   - Manually clean up the edges of the holes. The scanner tends to leave the edges of larger holes curved inward. Select and delete the connecting vertices. Then the excess surface is floating and can be deleted by hovering over it with the cursor and then pressing ''l'' (lower caps L) to select and then delete all linked vertices.   - Manually clean up the edges of the holes. The scanner tends to leave the edges of larger holes curved inward. Select and delete the connecting vertices. Then the excess surface is floating and can be deleted by hovering over it with the cursor and then pressing ''l'' (lower caps L) to select and then delete all linked vertices.
   - Merge together irregularities like outward or inward triangles. Try to make the edge of the hole somewhat smooth.   - Merge together irregularities like outward or inward triangles. Try to make the edge of the hole somewhat smooth.
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 {{:3d_modeling:blender:04_hole_fill_-_02_medium_-_delete_-_collage_arrows.jpg|}} {{:3d_modeling:blender:04_hole_fill_-_02_medium_-_delete_-_collage_arrows.jpg|}}
  
-=== Fill in the gap ===+== Fill in the gap ==
 - fill: ''Face > Fill'' (shortcut: ''alt + f'') - fill: ''Face > Fill'' (shortcut: ''alt + f'')
  
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-===== Retexture =====+==== Retexture ====
 New faces added to the mesh appear black or show random colours. They are referencing meaningless parts of the texture. Let's project the selected vertices to the texture and clone the surrounding texture onto that area. New faces added to the mesh appear black or show random colours. They are referencing meaningless parts of the texture. Let's project the selected vertices to the texture and clone the surrounding texture onto that area.
  
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 Retexturing is the same as described above. Retexturing is the same as described above.
  
-===== Normals =====+==== Normals ====
  
   - Go to edit mode and select all vertices   - Go to edit mode and select all vertices
  • 3d_modeling/blender/clean_up_occipital_3d_scan.1586267626.txt.gz
  • Last modified: 2020/04/07 06:53
  • by formlab