Sketcher ConstrainBlock/ja

Symmetric

Refraction (Snell's law)

Sketcher

Description

The Sketcher ConstrainBlock tool blocks edges in place with a single constraint. It is mainly intended for B-splines, which can be difficult to fully constrain otherwise.

The block constraint only affects the freely movable parts of an edge. Blocked edges can have other constraints, and applying additional constraints to a blocked edge can modify it.

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 block button.
   • Select the Sketch → Sketcher constraints → Constrain block option from the menu.
   • introduced in 1.0: Right-click in the 3D view and select the Constrain → Constrain block option from the context menu.
   • Use the keyboard shortcut: K then B.
3. The cursor changes to a cross with the tool icon.
4. Select a single edge.
5. A constraint is added.
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. Select one or more edges.
2. Invoke the tool as explained above, or with the following additional option:
   • introduced in 1.0: Right-click in the 3D view and select the Constrain block option from the context menu.
3. Depending on the selection one or more constraints are added.

Scripting

Sketch.addConstraint(Sketcher.Constraint('Block', Edge))

The Sketcher scripting page explains the values which can be used for Edge and contains further examples on how to create constraints from Python scripts.

Symmetric

Refraction (Snell's law)

Sketcher

Sketcher

• General: Create sketch, Edit sketch, Attach sketch, Reorient sketch, Validate sketch, Merge sketches, Mirror sketch, Leave sketch, View sketch, View section, Toggle grid, Toggle snap, Configure rendering order, Stop operation

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• Sketcher geometries: Point, Polyline, Line, Arc, Arc by 3 points, Arc of ellipse, Arc of hyperbola, Arc of parabola, Circle, Circle by 3 points, Ellipse, Ellipse by 3 points, Rectangle, Centered rectangle, Rounded rectangle, Triangle, Square, Pentagon, Hexagon, Heptagon, Octagon, Regular polygon, Slot, Arc slot, B-spline by control points, Periodic B-spline by control points, B-spline by knots, Periodic B-spline by knots, Toggle construction geometry

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• Sketcher constraints:
  • Dimensional constraints: Dimension, Horizontal distance, Vertical distance, Distance, Auto radius/diameter, Radius, Diameter, Angle, Lock
  • Geometric constraints: Coincident (unified), Coincident, Point on object, Horizontal/vertical, Horizontal, Vertical, Parallel, Perpendicular, Tangent or collinear, Equal, Symmetric, Block
  • Other constraints: Refraction (Snell's law)
  • Constraint tools: Toggle driving/reference constraint, Activate/deactivate constraint

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• Sketcher tools: Fillet, Chamfer, Trim, Split, Extend, External geometry, Carbon copy, Select origin, Select horizontal axis, Select vertical axis, Array transform, Polar transform, Scale transform, Offset geometry, Symmetry, Remove axes alignment, Delete all geometry, Delete all constraints

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• Sketcher B-spline tools: Convert geometry to B-spline, Increase B-spline degree, Decrease B-spline degree, Increase knot multiplicity, Decrease knot multiplicity, Insert knot, Join curves

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• Sketcher visual: Select unconstrained DoF, Select associated constraints, Select associated geometry, Select redundant constraints, Select conflicting constraints, Show/hide circular helper for arcs, Show/hide B-spline degree, Show/hide B-spline control polygon, Show/hide B-spline curvature comb, Show/hide B-spline knot multiplicity, Show/hide B-spline control point weight, Show/hide internal geometry, Switch virtual space

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• Additional: Sketcher Dialog, Preferences, Sketcher scripting

User documentation

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