Meshlab pour impression 3D

Cet article est une ébauche à compléter. Une ébauche est une entrée ayant un contenu (très) maigre et qui a donc besoin d'un auteur.

Importer des modèles 3D et exporter en .stl

On peut utiliser Meshlab pour transcoder à peu près n'importe quel format.

Par exemple, Google sketchup (free version) only can export to .DAE, the collada format, unless you install a so-called plugin. For most [Slicers and user interfaces for 3D printers slicers], you need an .STL. Some can read *.obj or *.ply formats. I suggest using .STL, since it is the standard for exchanging open source printable 3D objects.

Example to import .dae:

• File -> Import Mesh

You then could fix meshes and do other manipulations like changing size and position, but for beginners it's easier to use NetFabb for this. Therefore just save

To export as .stl:

• File -> Export Mesh as

Triangle reduction and repair

Meshlab includes several interesting algorithm for repairing and simplifying meshes.

Triangle reduction

Step 1

Menu File -> Import Mesh

Step 2

• Tick the Wireframe Icon on top

Step 3: Select the (maybe) best triangle reduction filter

Menu Filters -> Remeshing, simplification, and Reconstruction
Quadric Edge Collapse Decimation

Now in the small popup

• Tick "preserve Normal"
• Enter target number of faces or enter a fraction, e.g. 0.25
• Apply

Mesh repair

Finding out if your object is non-manifold:

Render -> Show non manif edges
Render -> Show non-manif vertices

Both operations will show a little box that tells how many elements are wrong. In addition, bad "spots" are painted in pink or red.

Here is a list of popular cleaning operations made by [https://www.cis.uab.edu/jj/soYouWantTo/cleanMesh.txt John K. Johnstone (retrieved oct. 2015):

Remove duplicate faces and vertices:

 Filters -> Cleaning and Repairing -> Remove Duplicate Faces
 Filters -> Cleaning and Repairing -> Remove Duplicated Vertex

Close holes:

  Filters -> Remeshing, Simplification and Reconstruction -> Close Holes

Orient faces (all faces must point outwards)

 Filters->Normals, Curvatures and Orientation->Re-Orient All Faces Coherently

Merging models into a single one (mashups)

Now let's assume that you have two or more objects that you would like to merge, i.e. in the simple sense of fusioning models that already in the right position. Aligning models and more complex "Mesh merging" are much more difficult procedures. Anyhow aligning with a tool like Netfabb or even Google sketchup is simple. In Netfab, align the models, then export each one separately. Then open each model in Meshlab.

Merging the easy way

Dans le cas le plus simple, les objets sont déjà en bonne position. Utilisez Netfabb par exemple. On peut déplacer des objets dans Meshlab, mais c'est difficile, donc mieux vaut le faire avant ...

• Import the STL Files (two or more)

   File -> Import Mesh 
   File -> Import Mesh 

• Menu Filters->Layer and Attribute Management->Flatten Visible Layers
• File->Export Mesh as

Liens

Autres logiciels

• Netfabb Basic, Netfabb Pro, etc.
• Voir aussi liste de http://meshrepair.org/