Adding and Removing Segments on Curves

You can add and remove segments on curves using different segment types and ratios.

Important:
  • In Me > Preferences > Common Preferences > 2D 3D View Display > Selection, Selection section, the Preselect in Geometry View option must be selected.
  • The minimum order of the curve must be 4. In case of an order lower to 4, it is automatically increased.

Before you begin: Open a 3D Shape containing a 3D curve with strongly and slightly curved areas.
  1. To start segment modeling, do one of the following:
    • In the work area, press Alt + middle-click on a curve and select Modify Curve Segment in the mouse menu.

      In the Segments Modeling panel, click to switch to subobject mode .

      Tip: If desired, click Analysis to hide the curvature diagnosis.
    • In the Sculpt panel, click Activate Controls and Segments and clear Control Points .

      Right-click a curve to open the Segment Modeling panel. Subobject selection mode is automatically selected.

  2. Click Insert/Delete .
  3. To insert segment boundaries, do one of the following:
    • Move the pointer on the curve and press Insert.
    • Click positions on the curve.
    Segment boundaries are inserted at the selected positions.

  4. To delete segment boundaries, do one of the following:
    • Move the pointer on the curve and press Delete.
    • Click the segment boundaries on the curve.
  5. Clear Insert/Delete and click Trim .

    Note: This trim option creates a datum element and not an OmniCut feature.

    • Trim the curve at a segment boundary keeping one side.
      1. Move the pointer to a segment. The curve region kept after the trim operation is highlighted.

        The pick position nearest to the next segment boundary determines the side to be kept.

      2. Click the segment to trim the curve.

    • Trim the curve at a segment boundary keeping both sides.
      1. Move the pointer to a segment boundary. The whole curve is highlighted. To distinguish left and right side of the limitation, different highlight properties are applied.

      2. Click the segment boundary to trim the curve.

    Tip: Press Ctrl and select multiple segment boundaries. The curve is trimmed at the selected segment boundaries when releasing the Ctrl key. Instead of the segment boundaries, the trimmed curve boundaries are now displayed.

    Click a segment boundary again while keeping the Ctrl key pressed to deselect a segment boundary.

  6. Clear Trim and use the Segment Numbers box to insert segment boundaries.
    If Segment Type Manual is selected, the segments are equally spaced along the curve.

    At the curve ends are displayed continuities.

  7. Click the continuity label at one of the curve ends to select the continuity to be kept at this side when modifying the inner segment boundaries.
  8. In the Segment Modeling panel or the More section of the Sculpt panel, select Segment Type Arc Length.

    Ratio determines the segment distribution:

    1. Set the Ratio 0.0 (Arc Length).
      The segments are equally spaced along the curve.

    2. Set the Ratio 1 (Curvature).
      The segments are distributed depending on the curvature degree.

      This may cause a deviation from the original curve which is displayed at the curve and in Deviation in the context menu.

    3. Move the pointer on the curve and press Alt + right-click.
    4. In the mouse menu, select 1/3 Curvature.
      The Ratio value in the Sculpt panel is set to 0.33.

    Tip: You can also select the segment type and ratio using the mouse menu with Alt + right-click on preselected segment.
  9. Click Order or , respectively, to change the order accordingly.
  10. If deselected, click Analysis to display the curvature analysis.


  11. Modify the view and then a segment.
    The curvature analysis is displayed in the original direction.

  12. Undo the segment modification and click Curvature Analysis Auto Direction .
  13. Repeat the segment modification.
    The curvature analysis is displayed according to the moved direction.