Sketcher CreateEllipseByCenter

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Sketcher CreateEllipseByCenter

Menu location
Sketch → Sketcher geometries → Create ellipse by center
Workbenches
Sketcher
Default shortcut
G E E
Introduced in version
0.15
See also
Sketcher CreateArcOfEllipse

Description

The Sketcher CreateEllipseByCenter tool creates an ellipse by its center, an endpoint of one of its axes, and a point along the ellipse. introduced in version 0.22: Or optionally by the endpoints of one of its axes and a point along the ellipse.

Ellipse (white) with internal geometry (dark yellow)

Usage

See also: Drawing aids.

Pos-OVP = Positional On-View-Parameters. introduced in version 0.22
Dim-OVP = Dimensional On-View-Parameters. introduced in version 0.22

  1. There are several ways to invoke the tool:
    • Press the Ellipse by center, radius, rim point button.
    • Select the Sketcher → Sketcher geometries → Create ellipse by center option from the menu.
    • Use the keyboard shortcut: G then E, then E.
  2. The cursor changes to a white cross with the current tool mode icon.
  3. The Ellipse parameters section (introduced in version 0.22) is added at the top of the Sketcher Dialog.
  4. Optionally press the M key or select from the dropdown list in the parameters section to change the tool mode:
    • Center:
      1. Pick the center of the ellipse. Or with Pos-OVP: enter its X and/or Y coordinate.
      2. Pick an endpoint of one of the axes of the ellipse, this also defines one of its radii. Or with Dim-OVP: enter this radius and/or the angle of this axis.
      3. Pick a point to define the other radius of the ellipse. Or with Dim-OVP: enter this radius.
    • Axis endpoints: introduced in version 0.22
      1. Pick the endpoints of one of the axes of the ellipse, this also defines one of its radii. Or with Pos-OVP: enter their X and/or Y coordinates. No constraints are created for these points.
      2. Pick a point to define the other radius of the ellipse. Or with Pos-OVP: enter its X and/or Y coordinate. No constraint is created for this point.
  5. The ellipse is created, including a set of internal geometry (major axis, minor axis and two foci), and applicable Pos-OVP and Dim-OVP based constraints are added.
  6. If the tool runs in continue mode:
    1. Optionally keep creating ellipses.
    2. To finish, right-click or press Esc, or start another geometry or constraint creation tool.

Notes

  • Elements of the internal geometry can be deleted. They can be recreated at any time with Sketcher RestoreInternalAlignmentGeometry.
  • Once created, the major and minor axes of an ellipse are strict and cannot be swapped by resizing. This is a consequence of the solver parametrization and the same strict behavior of OpenCASCADE. An ellipse must be rotated to swap its axes.