Surface: Curve su Mesh

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This page is a translated version of the page Surface CurveOnMesh and the translation is 26% complete.
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Arrow-left.svg Previous: Surface ExtendFace.svg ExtendFace

Surface CurveOnMesh.svg CurveOnMesh

Posizione nel menu
Surface → Curve on mesh...
Avvio veloce
Introdotto nella versione
Vedere anche


Surface CurveOnMesh.svg Surface CurveOnMesh creates approximated spline segments on top of a selected mesh.

If the object is not a Mesh, but a parametric Shape or surface, it must be converted first to a mesh using Mesh FromPartShape.svg Mesh FromPartShape.

These edges created on top of the mesh may be further used to re-create the surface in a parametric way by using tools such as Surface GeomFillSurface.svg GeomFillSurface and Surface Sections.svg Sections.

Surface CurveOnMesh mesh example.png Surface CurveOnMesh example.png

Surface CurveOnMesh surface example.png

Above left: mesh object with selected points on the surface. Above right: splines created by picking several points on the mesh. Lower left: a parametric surface reconstructed from the approximated splines, using Surface Sections.


  1. Selezionare Surface → Curve on mesh... nel menu.
  2. Passaggi secondo le esigenze.
  3. Impostare le opzioni e premere OK.

After pressing Start, the context menu (right-click) in the 3D view shows various options beside Create.

  • Close wire: if at least three points have been picked, this option will be available to join the last point to the first point with a line.
  • Clear: it will erase the tentative points that have been picked on the mesh, and will allow you to pick new ones.
  • Cancel: it will erase the tentative points that have been picked, and will stop the picking operation. Press Start again to pick points once more.


(Editor: this information must be verified)

Wire section:

  • Snap tolerances to vertices: it defaults to 10 px; it indicates the minimum distance between one point and another when picking with the pointer.
  • Split threshold: it defaults to 45 deg; it indicates the angular deviation from one point in the mesh to another point necessary to create a new spline instead of extending the previous spline.

Spline approximation, if it is CheckBoxTrue.svg checked, it will create spline objects, otherwise, it will create simple straight line objects (polyline).

  • Tolerance to mesh: it defaults to 0.2. It is a parameter that takes into account the imperfections of the mesh; the smaller this number the more precise it will consider the mesh, particularly if it is a very fine mesh.
  • Continuity: it defaults to C2. It determines the continuity of the spline; it can be C0 (touching), C1 (tangent), C2 (curvature), and C3 (acceleration curvature).
  • Maximum curve degree: it defaults to 5. It determines the maximum degree of the spline to approximate the surface; it can be a value from 1 to 8.


  • DatiProperty:
  • VistaProperty:

If CheckBoxTrue.svg Spline approximation is checked, the Curve on mesh tool creates a Part Spline.svg Part Spline (Part::Spline class) which is derived from the basic Part Feature (Part::Feature class), therefore it shares all the latter's properties.

In addition to the properties described in Part Feature, the Part Spline has the following properties in the property editor.



  • VistaControl Points (Bool): it defaults to false; if set to true, it will show an overlay with the control points of the surface.

Arrow-left.svg Previous: Surface ExtendFace.svg ExtendFace