Mesh Scripting
Introduction[edit | edit source]
To get access to the Mesh module you have to import it first:
import Mesh
Creation[edit | edit source]
To create an empty mesh object just use the standard constructor:
mesh = Mesh.Mesh()
You can also create an object from a file:
mesh = Mesh.Mesh("D:/temp/Something.stl")
Or create it out of a set of triangles described by their corner points:
triangles = [
# triangle 1
[-0.5000, -0.5000, 0.0000], [0.5000, 0.5000, 0.0000], [-0.5000, 0.5000, 0.0000],
#triangle 2
[-0.5000, -0.5000, 0.0000], [0.5000, -0.5000, 0.0000], [0.5000, 0.5000, 0.0000],
]
meshObject = Mesh.Mesh(triangles)
Mesh.show(meshObject)
The Mesh-Kernel takes care of creating a topologically correct data structure by sorting coincident points and edges.
Modeling[edit | edit source]
To create regular geometries you can use one of the create*() methods. A torus, for instance, can be created as follows:
m = Mesh.createTorus(8.0, 2.0, 50)
Mesh.show(m)
The first two parameters define the radii of the torus and the third parameter is a sub-sampling factor for how many triangles are created. The higher this value the smoother the mesh.
The Mesh module also provides three Boolean methods: union(), intersection() and difference():
m1, m2 # are the input mesh objects
m3 = Mesh.Mesh(m1) # create a copy of m1
m3.unite(m2) # union of m1 and m2, the result is stored in m3
m4 = Mesh.Mesh(m1)
m4.intersect(m2) # intersection of m1 and m2
m5 = Mesh.Mesh(m1)
m5.difference(m2) # the difference of m1 and m2
m6 = Mesh.Mesh(m2)
m6.difference(m1) # the difference of m2 and m1, usually the result is different to m5
Here is an example that creates a pipe using the difference() method:
import FreeCAD, Mesh
cylA = Mesh.createCylinder(2.0, 10.0, True, 1.0, 36)
cylB = Mesh.createCylinder(1.0, 12.0, True, 1.0, 36)
cylB.Placement.Base = (FreeCAD.Vector(-1, 0, 0)) # move cylB to avoid co-planar faces
pipe = cylA
pipe = pipe.difference(cylB)
pipe.flipNormals() # somehow required
doc = FreeCAD.ActiveDocument
obj = d.addObject("Mesh::Feature", "Pipe")
obj.Mesh = pipe
doc.recompute()
Notes[edit | edit source]
An extensive, though hard to use, source of mesh related scripting are the unit test scripts of the Mesh module.
In these unit tests literally all methods are called and all properties/attributes are tweaked.
So if you are bold enough, take a look at the Unit Test module.
See also: Mesh API.
- FreeCAD scripting: Python, Introduction to Python, Python scripting tutorial, FreeCAD Scripting Basics
- Modules: Builtin modules, Units, Quantity
- Workbenches: Workbench creation, Gui Commands, Commands, Installing more workbenches
- Meshes and Parts: Mesh Scripting, Topological data scripting, Mesh to Part, PythonOCC
- Parametric objects: Scripted objects, Viewproviders (Custom icon in tree view)
- Scenegraph: Coin (Inventor) scenegraph, Pivy
- Graphical interface: Interface creation, Interface creation completely in Python (1, 2, 3, 4, 5), PySide, PySide examples beginner, intermediate, advanced
- Macros: Macros, How to install macros
- Embedding: Embedding FreeCAD, Embedding FreeCADGui
- Other: Expressions, Code snippets, Line drawing function, FreeCAD vector math library (deprecated)
- Hubs: User hub, Power users hub, Developer hub
- Miscellaneous: Import Mesh, Export Mesh, Mesh From Shape, Regular solid, Unwrap Mesh, Unwrap Face
- Modifying: Harmonize Normals, Flip Normals, Fill Holes, Close Holes, Add Triangle, Remove Components, Remove Components Manually, Smooth, Refinement, Decimate, Scale
- Boolean: Union, Intersection, Difference
- Cutting: Cut, Trim, Trim With Plane, Section From Plane, Cross-Sections
- Components and segmentation: Merge, Split by Components, Segmentation, Segmentation From Best-Fit Surfaces
- Analyze: Evaluate and Repair, Face Info, Curvature Plot, Curvature Info, Evaluate Solid, Bounding Box Info
- Additional: Import Export Preferences, OpenSCAD Workbench, Mesh Scripting