Sketcher CreateEllipseByCenter: Difference between revisions

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|Shortcut={{KEY|G}} {{KEY|E}} {{KEY|E}}
|Shortcut={{KEY|G}} {{KEY|E}} {{KEY|E}}
|Version=0.15
|Version=0.15
|SeeAlso=[[Sketcher_CreateEllipseBy3Points|Sketcher Ellipse by 3 Points]], [[Sketcher_CreateCircle|Sketcher Circle]], [[Sketcher_CreateArcOfEllipse|Sketcher Arc of Ellipse]]
|SeeAlso=[[Sketcher_CreateArcOfEllipse|Sketcher CreateArcOfEllipse]]
}}
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The [[Image:Sketcher_CreateEllipseByCenter.svg|24px]] [[Sketcher_CreateEllipseByCenter|Sketcher CreateEllipseByCenter]] tool creates an ellipse by its center, an endpoint of its major axis, and a point along the ellipse or its minor radius. {{Version|0.22}}: Or optionally by the endpoints of its major axis and a point along the ellipse.
The [[Image:Sketcher_CreateEllipseByCenter.svg|24px]] [[Sketcher_CreateEllipseByCenter|Sketcher CreateEllipseByCenter]] tool creates an ellipse by its center, an endpoint of one of its axes, and a point along the ellipse. {{Version|0.22}}: Or optionally by both endpoints of one of its axes and a point along the ellipse.

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[[Image:Sketcher_CreateEllipseByCenter_Example.png]]
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{{Caption|Ellipse (white) with internal geometry (dark yellow)}}


==Usage== <!--T:4-->
==Usage== <!--T:4-->


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See also: [[Sketcher_Workbench#Drawing_aids|Drawing aids]].
See also: [[Sketcher_Workbench#Drawing_aids|Drawing aids]].


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Pos-OVP = Positional [[Sketcher_Preferences#General|On-View-Parameters]]. {{Version|0.22}}<br>
Pos-OVP = Positional [[Sketcher_Preferences#General|On-View-Parameters]]. {{Version|0.22}}<br>
Dim-OVP = Dimensional On-View-Parameters. {{Version|0.22}}
Dim-OVP = Dimensional On-View-Parameters. {{Version|0.22}}


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# There are several ways to invoke the command:
# There are several ways to invoke the tool:
#* Press the {{Button|[[Image:Sketcher_CreateEllipseByCenter.svg|16px]] [[Sketcher_CreateEllipseByCenter|Ellipse by center, major radius, point]]}} button.
#* Press the {{Button|[[Image:Sketcher_CreateEllipseByCenter.svg|16px]] [[Sketcher_CreateEllipseByCenter|Ellipse by center, radius, rim point]]}} button.
#* Select the {{MenuCommand|Sketcher → Sketcher geometries → [[Image:Sketcher_CreateEllipseByCenter.svg|16px]] Create Ellipse by center}} option from the menu.
#* Select the {{MenuCommand|Sketcher → Sketcher geometries → [[Image:Sketcher_CreateEllipseByCenter.svg|16px]] Create ellipse by center}} option from the menu.
#* The keyboard shortcut: {{KEY|G}} then {{KEY|E}}, {{KEY|E}}.
#* Use the keyboard shortcut: {{KEY|G}} then {{KEY|E}}, then {{KEY|E}}.
# The cursor changes to a white cross with the command icon.
# The cursor changes to a cross with the current tool mode icon.
# The '''Ellipse parameters''' section ({{Version|0.22}}) is added at the top of the [[Sketcher_Dialog|Sketcher Dialog]].
# The '''Ellipse parameters''' section ({{Version|0.22}}) is added at the top of the [[Sketcher_Dialog|Sketcher Dialog]].
# Optionally press the {{KEY|M}} key or select from the dropdown list in the parameters section to change the tool '''Mode''':
# Optionally press the {{KEY|M}} key or select from the dropdown list in the parameters section to change the tool mode:
#* [[Image:Sketcher_CreateEllipseByCenter.svg|16px]] '''Center''':
#* [[Image:Sketcher_CreateEllipseByCenter.svg|16px]] '''Center''':
#*# Pick the center of the ellipse. Or with Pos-OVP: enter its X and/or Y coordinate.
#*# Pick the center of the ellipse. Or with Pos-OVP: enter its X and/or Y coordinate.
#*# Pick a point to set the major radius, and the orientation of the major axis. Or with Dim-OVP: enter the major radius of the ellipse and the angle of the major axis.
#*# 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.
#*# Pick a point on the outline of the ellipse to define the minor radius. Or with Pos-OVP: enter the minor radius.
#*# Pick a point to define the other radius of the ellipse. Or with Dim-OVP: enter this radius.
#* [[Image:Sketcher_CreateEllipseBy3Points.svg|16px]] '''Axis endpoints and radius''': {{Version|0.22}}
#* [[Image:Sketcher_CreateEllipseBy3Points.svg|16px]] '''Axis endpoints''': {{Version|0.22}}
#*# Pick three points of the ellipse outline. Or with Pos-OVP: enter their X and/or Y coordinates.
#*# 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.
#*# 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.
# The geometry is created and applicable Pos-OVP and Dim-OVP based constraints are added (none for Axis endpoints and radius). A set of internal geometry aligned to it (major diameter, minor diameter, two foci) is also created. The internal geometry can be manually deleted if not needed, and recreated later. See [[Sketcher_RestoreInternalAlignmentGeometry|Sketcher Show Hide Internal Geometry]].
# 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.
# If the tool runs in [[Sketcher_Workbench#Continue_modes|continue mode]]:
## Optionally keep creating ellipses.
## To finish, right-click or press {{KEY|Esc}}, or start another geometry or constraint creation tool.


==Peculiarities== <!--T:15-->
==Notes== <!--T:19-->


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* Elements of the internal geometry can be deleted. They can be recreated at any time with [[Sketcher_RestoreInternalAlignmentGeometry|Sketcher RestoreInternalAlignmentGeometry]].
* Major and minor axes of ellipses are strict and cannot be swapped by resizing the ellipse. This is a consequence of the solver parametrization used (center (x,y), focus1 (x,y) and minor radius length (b)) and the same strict behavior of OpenCascade. The ellipse must be rotated to swap the axes.
* 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|OpenCASCADE]]. An ellipse must be rotated to swap its axes.
* Ellipse can function as a circle when its major and minor diameter lines are deleted, and one of the foci is constrained to coincide with the center. But radius constraint won't work on such a circle.
* Moving the ellipse by edge is the same as moving ellipse's center.





Revision as of 09:24, 18 April 2024

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 both 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 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.