Sketcher ConstrainPerpendicular: Difference between revisions

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The [[Image:Sketcher_ConstrainPerpendicular.svg|24px]] [[Sketcher_ConstrainPerpendicular|Sketcher ConstrainPerpendicular]] command defines two lines to be perpendicular (i.e. orthogonal) to each other, or two curves to be perpendicular at their intersection. Lines are treated infinite, and arcs are treated as full circles/ellipses. The constraint is also capable of connecting two curves, forcing them perpendicular at the joint, similarly to {{Button|[[File:Sketcher_ConstrainTangent.svg|16px]] [[Sketcher_ConstrainTangent|Constrain tangent]]}}.
The [[Image:Sketcher_ConstrainPerpendicular.svg|24px]] [[Sketcher_ConstrainPerpendicular|Sketcher ConstrainPerpendicular]] tool constrains two lines to be perpendicular, or two edges to be perpendicular at their intersection. One of the lines or edges can be an axis. Lines are treated as infinite, and open curves are virtually extended as well. The constraint can also connect two edges, forcing them to be perpendicular at the joint.


==Usage== <!--T:32-->
==Usage== <!--T:32-->
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See also: [[Sketcher_Workbench#Drawing_aids|Drawing aids]].
See also: [[Sketcher_Workbench#Drawing_aids|Drawing aids]].


# Do one of the following (optional if the tool will run in [[Sketcher_Workbench#Continue_modes|continue mode]]):
===[[Sketcher_Workbench#Continue_modes|Continue mode]]===

#* Select two edges. One of the edges must be a straight line. The other can be a line or a curve, but not a B-spline.
# Make sure there is no selection.
#* select two endpoints belonging to different edges.
#* Select an edge and the endpoint of another edge (in any order).
#* Select a point and two edges (idem).
# There are several ways to invoke the tool:
# There are several ways to invoke the tool:
#* Press the {{Button|[[Image:Sketcher_ConstrainPerpendicular.svg|16px]] [[Sketcher_ConstrainPerpendicular|Constrain perpendicular]]}} button.
#* Press the {{Button|[[Image:Sketcher_ConstrainPerpendicular.svg|16px]] [[Sketcher_ConstrainPerpendicular|Constrain perpendicular]]}} button.
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#* {{Version|0.22}}: Right-click in the [[3D_view|3D view]] and select the {{MenuCommand|Constrain → [[Image:Sketcher_ConstrainPerpendicular.svg|16px]] Constrain perpendicular}} option from the context menu.
#* {{Version|0.22}}: Right-click in the [[3D_view|3D view]] and select the {{MenuCommand|Constrain → [[Image:Sketcher_ConstrainPerpendicular.svg|16px]] Constrain perpendicular}} option from the context menu.
#* Use the keyboard shortcut: {{KEY|N}}.
#* Use the keyboard shortcut: {{KEY|N}}.
# The cursor changes to a white cross with the tool icon.
# If the tool runs in [[Sketcher_Workbench#Continue_modes|continue mode]]:
# Do one of the following:
## The cursor changes to a white cross with the tool icon.
#* Select two edges. One of the edges must be a straight line or an axis. The other can be any edge except a B-spline.
## Optionally keep selecting elements:
##* Select two edges (see above).
#* Select a point and two edges (in that order).
##* Select a point and two edges (in that order).
#* Select an edge, a point and another edge (idem).
# A Perpendicular constraint is added. If a point and two edges have been selected, up to two [[Sketcher_ConstrainPointOnObject|Point onto object constraints]] can also be added. See [[#Between_two_edges_at_point|Examples]].
##* Select an edge, a point and another edge (idem).
# Optionally keep creating constraints.
## To finish, right-click or press {{KEY|Esc}}, or start a another constraints or geometries tool.
# To finish, right-click or press {{KEY|Esc}}, or start another geometry or constraint creation tool.


===Run-once mode===
===Between two curves (direct perpendicularity)=== <!--T:7-->


# Do one of the following:
<!--T:33-->
#* Select two edges (see above).
[[Image:Sketcher ConsraintPerpendicular mode1.png|600px]]
#* Select two endpoints belonging to different edges.
#* Select an edge and the endpoint of another edge (in any order).
#* Select a point and two edges (idem).
# Invoke the tool as explained above, or with the following additional option:
#* {{Version|0.22}}: Right-click in the [[3D_view|3D view]] and select the {{MenuCommand|[[Image:Sketcher_ConstrainPerpendicular.svg|16px]] Constrain perpendicular}} option from the context menu.
# A Perpendicular constraint is added. If a point and two edges have been selected, up to two [[Sketcher_ConstrainPointOnObject|Point onto object constraints]] can also be added. See [[#Between_two_edges_at_point|Examples]].


==Examples==
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Two curves will be made perpendicular at point of their intersection (either real, or of curves' extensions), and the point of intersection will be implicit. This mode is applied if two curves were selected.


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===Between two edges=== <!--T:7-->
'''Accepted selection:'''
* line + line, circle, arc
* circle, arc + circle, arc
If direct perpendicularity between selected curves is not supported (e.g. between a line and an ellipse), a helper point will be added to sketch automatically, and perpendicular-via-point will be applied.


</translate>
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[[Image:Sketcher_ConsraintPerpendicular_mode1.png|400px]]
Unlike for tangency, it is perfectly fine to reconstruct the point of perpendicularity by creating a point and constraining it to lie on both curves (thus constraining the point to the intersection).
<translate>


The two edges are made perpendicular at their (virtual) intersection. If one of the edges is a [[Sketcher_Workbench#Sketcher_CompCreateConic|conic]], a [[Sketcher_CreatePoint|Point object]] that has a [[Sketcher_ConstrainPointOnObject|Point onto object constraint]] with both (extended) edges is added.
===Between two endpoints (point-to-point perpendicularity)=== <!--T:11-->


<!--T:34-->
===Between two endpoints=== <!--T:11-->

[[Image:Sketcher ConsraintPerpendicular mode2.png|600px]]
</translate>
[[Image:Sketcher_ConsraintPerpendicular_mode2.png|400px]]
<translate>


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In this mode, the endpoints are made coincident, and the joint is made to be right angle. This mode is applied when two endpoints of two curves were selected.
The endpoints are made coincident, and the edges are made perpendicular at that point.


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===Between edge and endpoint=== <!--T:14-->
'''Accepted selection:'''
* endpoint of line/arc/arc-of-ellipse + endpoint of line/arc/arc-of-ellipse (i.e., two endpoints of any two curves)


</translate>
===Between curve and endpoint (point-to-curve perpendicularity)=== <!--T:14-->
[[Image:Sketcher_ConsraintPerpendicular_mode3.png|400px]]

<translate>
<!--T:35-->
[[Image:Sketcher ConsraintPerpendicular mode3.png|600px]]


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In this mode, an endpoint of one curve is constrained to lie on the other curve, and the curves are forced perpendicular at the point. This mode is applied when a curve and an endpoint of another curve were selected.
The endpoint of one edge is constrained to lie on the other edge, and the edges are made perpendicular at that point.


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===Between two edges at point=== <!--T:17-->
'''Accepted selection:'''
* line, circle, arc, ellipse, arc-of-ellipse + endpoint of line/arc/arc-of-ellipse (i.e., any curve + endpoint of any curve)


</translate>

[[Image:Sketcher_ConsraintPerpendicular_mode4.png|400px]]
===Between two curves at point (perpendicular-via-point) (v0.15)=== <!--T:17-->
<translate>

<!--T:36-->
[[Image:Sketcher ConsraintPerpendicular mode4.png|600px]]


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The two edges are made perpendicular at a given point. The point can be any point, e.g. the center of a circle, the endpoint of an edge, or the origin, it can belong to one of the edges, and it can also be a [[Sketcher_CreatePoint|Point object]]. If required [[Sketcher_ConstrainPointOnObject|Point onto object constraint(s)]] are added to ensure the point lies on both (extended) edges. These additional constraints are called [[Sketcher_helper_constraint|helper constraints]].
In this mode, two curves are made perpendicular, and the point of perpendicularity is tracked. This mode is applied when two curves and a point were selected.

<!--T:19-->
'''Accepted selection:'''
* any line/curve + any line/curve + any point
"Any point" can be a lone point, or a point of something, e.g. a center of a circle, an endpoint of an arc, or the origin.

<!--T:20-->
For the constraint to work correctly, the point must be on both curves. So, as the constraint is invoked, the point will be automatically constrained onto both curves ([[Sketcher_helper_constraint|helper constraints]] will be added, if necessary), and the curves will be forced perpendicular at the point. These [[Sketcher_helper_constraint|helper constraints]] are plain regular constraints. They can be added manually, or deleted.

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Compared to direct perpendicular, this constraint is slower, because there are mode degrees of freedom involved, but it supports ellipses.

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The placement of the point before the constraint is applied is a hint for the solver for where the perpendicularity should be.


==Scripting== <!--T:23-->
==Scripting== <!--T:23-->

Revision as of 17:38, 25 March 2024

This documentation is a work in progress. Please don't mark it as translatable since it will change in the next hours and days.

Sketcher ConstrainPerpendicular

Menu location
Sketch → Sketcher constraints → Constrain perpendicular
Workbenches
Sketcher
Default shortcut
N
Introduced in version
-
See also
Sketcher Constrain angle

Description

The Sketcher ConstrainPerpendicular tool constrains two lines to be perpendicular, or two edges to be perpendicular at their intersection. One of the lines or edges can be an axis. Lines are treated as infinite, and open curves are virtually extended as well. The constraint can also connect two edges, forcing them to be perpendicular at the joint.

Usage

See also: Drawing aids.

Continue mode

  1. Make sure there is no selection.
  2. There are several ways to invoke the tool:
    • Press the Constrain perpendicular button.
    • Select the Sketch → Sketcher constraints → Constrain perpendicular option from the menu.
    • introduced in version 0.22: Right-click in the 3D view and select the Constrain → Constrain perpendicular option from the context menu.
    • Use the keyboard shortcut: N.
  3. The cursor changes to a white cross with the tool icon.
  4. Do one of the following:
    • Select two edges. One of the edges must be a straight line or an axis. The other can be any edge except a B-spline.
    • Select a point and two edges (in that order).
    • Select an edge, a point and another edge (idem).
  5. A Perpendicular constraint is added. If a point and two edges have been selected, up to two Point onto object constraints can also be added. See Examples.
  6. Optionally keep creating constraints.
  7. To finish, right-click or press Esc, or start another geometry or constraint creation tool.

Run-once mode

  1. Do one of the following:
    • Select two edges (see above).
    • Select two endpoints belonging to different edges.
    • Select an edge and the endpoint of another edge (in any order).
    • Select a point and two edges (idem).
  2. Invoke the tool as explained above, or with the following additional option:
  3. A Perpendicular constraint is added. If a point and two edges have been selected, up to two Point onto object constraints can also be added. See Examples.

Examples

Between two edges

The two edges are made perpendicular at their (virtual) intersection. If one of the edges is a conic, a Point object that has a Point onto object constraint with both (extended) edges is added.

Between two endpoints

The endpoints are made coincident, and the edges are made perpendicular at that point.

Between edge and endpoint

The endpoint of one edge is constrained to lie on the other edge, and the edges are made perpendicular at that point.

Between two edges at point

The two edges are made perpendicular at a given point. The point can be any point, e.g. the center of a circle, the endpoint of an edge, or the origin, it can belong to one of the edges, and it can also be a Point object. If required Point onto object constraint(s) are added to ensure the point lies on both (extended) edges. These additional constraints are called helper constraints.

Scripting

Perpendicular Constraint can be created from macros and from the python console by using the following:

# direct perpendicularity
Sketch.addConstraint(Sketcher.Constraint('Perpendicular',icurve1,icurve2))

# point-to-point perpendicularity
Sketch.addConstraint(Sketcher.Constraint('Perpendicular',icurve1,pointpos1,icurve2,pointpos2))

# point-to-curve perpendicularity
Sketch.addConstraint(Sketcher.Constraint('Perpendicular',icurve1,pointpos1,icurve2))

# perpendicular-via-point (plain constraint, helpers are not added automatically)
Sketch.addConstraint(Sketcher.Constraint('PerpendicularViaPoint',icurve1,icurve2,geoidpoint,pointpos))

where:

  • Sketch is a sketch object
  • icurve1, icurve2 are two integers identifying the curves to be made perpendicular. The integers are indexes in the sketch (the value, returned by Sketch.addGeometry).
  • pointpos1, pointpos2 should be 1 for start point and 2 for end point.
  • geoidpoint and pointpos in PerpendicularViaPoint are the indexes specifying the point of perpendicularity.

The Sketcher scripting page explains the values which can be used for icurve1, icurve2, pointpos1, pointpos2 and geoidpoint, and contains further examples on how to create constraints from Python scripts.