Mesh Workbench/ja

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メッシュワークベンチでは三角形メッシュを取り扱えます。メッシュは3Dオブジェクトの特別なタイプの一つで、エッジと角(頂点とも呼ばれます)によってつながった三角形によって構成されます。

An example of a mesh object

メッシュオブジェクトの一例

SketchupBlenderMaya3d studio maxといった多くの3Dアプリケーションでは基本となる3Dオブジェクトのタイプとしてメッシュを使用しています。これはメッシュが頂点(点)、エッジ、(三角形)面のみからなる非常にシンプルなオブジェクトで作成や変更、分割、伸縮をとても簡単に行うことができ、劣化なしで容易にアプリケーション間でのやり取りができるためです。また非常にシンプルなデータからできているので3Dアプリケーションは非常に大量のデータであっても普通は問題を起こすことなく扱うことができます。これらの理由からしばしばメッシュは映画やアニメーション、画像作成といったアプリケーションで取り扱う3Dオブジェクトの選択肢となります。

In the field of engineering, however, meshes present one big limitation: They are very dumb objects, only composed of points, lines and faces. They are only made of surfaces, and have no mass information, so they don't behave as solids. In a mesh there is no automatic way to know if a point is inside or outside the object. This means that all solid-based operations, such as addition or subtraction, are always a bit difficult to perform on meshes, and return errors often.

In FreeCAD, since it is an engineering application, we would obviously prefer to work with more intelligent types of 3D objects, that can carry more information, such as mass, solid behaviour, or even custom parameters. The mesh module was first created to serve as a testbed, but to be able to read, manipulate and convert meshes is also highly important for FreeCAD. Very often, in your workflow, you will receive 3D data in mesh format. You will need to handle that data, analyse it to detect errors or other problems that prevent converting them to more intelligent objects, and finally, convert them to more intelligent objects, handled by the Part Module.

Using the mesh module

The mesh module has currently a very simple interface, all its functions are grouped in the Mesh menu entry. The most important operations you can currently do with meshes are:



  • Regular solid... Create mesh primitives, like cubes, cylinders, cones, or spheres:
    • Create a mesh cube
    • Create a mesh cylinder
    • Create a mesh cone
    • Create a mesh sphere
    • Create a mesh ellipsoid
    • Create a mesh torus


  • Do Boolean operations with meshes
    • Union: Does a union (fusion) on meshes
    • Intersection: Does an intersection (common) on meshes
    • Difference: Does a difference (cut) on meshes



These are only some of the basic operations currently present in the Mesh module interface.
More mesh tools are available in the OpenSCAD Workbench.
But the FreeCAD meshes can also be handled in many more ways by scripting.

Links


PartDesign Workbench
OpenSCAD Module