Breaking Surfaces

You can trim a surface into two or more parts using any combination of curves, planes, and surfaces.

Before you begin:
  • Open an existing 3D shape.
  • Click Shading with Edges in the View section of the action bar.
See Also
Break Surface Dialog Box
About Breaking Surfaces
Breaking Curves
Restoring a Surface or Curve
  1. From the Edition section of the action bar, click Break Surface .
  2. In the Elements box, select the surface.
    The edges of the surface appear in green.

  3. In the Limitation box, select the trimming curves.

    You can directly select an intersection curve resulting from a Cutting Plane Analysis as limiting element.

    The limiting elements appear in red.

  4. Optional: Click on the surface to create an instant iso-parametric curve as the limiting element. This curve can be positioned using the handle which appears on the curve.
    • Right-click on a point handle and select Propagate to propagate the isoparametric curve onto adjacent surfaces.
    • Clear Propagate Isoparametric Curve before creating an instant iso-parametric curve to avoid the propagation of an iso-parametric curve onto adjacent surfaces.


  5. Optional: Right-click a Limitation tag to access the context menu.
  6. Click Apply.
    The surface is trimmed.

    By default, only one trimmed element is kept (the part of the surface bounded by the solid lines).

  7. Click the segment to be kept to switch between kept and removed part.
    The edges of the segment appear as solid lines.

  8. Right-click any re-limited element to display the context menu.
    • Keep all: Keeps all parts of the all surfaces.
    • Keep all but this: Keeps all parts of all surfaces except the selected one.
    • Remove all but this: Removes all parts of all surfaces except the selected one.

    Tip: Hold down Ctrl and select the elements to keep or remove them.

  9. In the Projection area, click Along Robot .
  10. Click Apply.
    Elements that do not lie on the trimmed elements will be projected (pseudo-intersections) onto the trimming elements according to the Robot direction.
  11. In the Projection area, click Along Normal , then click Apply.
    Elements that do not lie on the trimmed elements will be projected (pseudo-intersections) onto the trimming elements according to the normal direction.
  12. In the Trim Type area, click Surface Trim , then click Apply.
    • The maximum deviation is displayed and on the geometry (yellow label).
    • The maximum degree variation allowed for each patch of the new surface as compared to patches of the initial surface can be modified.
  13. In the Order area, select Keep Order to edit the U and V values.
  14. Optional: In the Extrapolation area, click Tangential Extrapolation .
  15. Click Apply.
    The surface segments are added along the tangent direction.
  16. Optional: Click IsoUV Extrapolation .
  17. Click Apply.
    The input elements are trimmed by extrapolating the limiting elements. By default, the shortest iso side in U direction is used to trim the surface.

    4-directional arrow handles appear at the end points of the limiting elements to select any of the iso-extrapolated sides to trim the surface in both IsoU and/or IsoV direction.

  18. Click one or more arrows to select the required iso side(s).
    The trim result appears in the direction of the arrow handles.

    Notes:
    • Undo/Redo is provided for arrow handle selection.
    • Arrow handles appear only if an extrapolation is required.
  19. Click OK.

Note: The Keep Original setting in the Tools Dashboard area of the App Options panel is locally saved for the Break command when you exit the command by clicking OK.