Sketcher CreateBSplineByInterpolation
Sketcher CreateBSplineByInterpolation |
Menu location |
---|
Sketch → Sketcher geometries → Interpolate B-spline |
Workbenches |
Sketcher |
Default shortcut |
G B I |
Introduced in version |
0.21 |
See also |
Sketcher periodic B-spline |
Description
This tool creates a B-spline curve passing through given points. See this page for more info about B-splines.
Usage
- Press the B-spline by knots button.
- Create a series of points by clicking in the 3D view. While the command is active, the created points are connected with straight lines.
- Optionally press M before terminating the input to define the multiplicity of the knot at the last defined point (note that this may not always be respected, see limitations for details).
- Optionally press Backspace before terminating the input to delete the last created control point.
- Right-click, or pick the first curve point, to terminate the input and generate the curve.
- Depending on preferences, the tool may remain active to trace a new curve. Right-click again to exit the command.
Notes
Limitations
- The resultant curve is no different than a curve defined through control points. So all related limitations apply. See Sketcher CreateBSpline.
- The B-splines created are always cubic (i.e. with degree 3).
- The defined multiplicity may not always be respected:
- For a periodic spline, the first knot (coincident with last) always has a multiplicity of 2.
- For a non-periodic spline, the first and last knots always have a multiplicity of 4.
- If the points just before and just after have multiplicities >=3, the piece between these two is fully continuous, and this (middle) point will only be constrained with point-on-object. If a knot is needed, consider using the insert knot tool.
Sketcher
- General: Create sketch, Edit sketch, Map sketch to face, Reorient sketch, Validate sketch, Merge sketches, Mirror sketch, Leave sketch, View sketch, View section, Toggle grid, Toggle snap, Configure rendering order, Stop operation
- Sketcher geometries: Point, Line, Arc, Arc by 3 points, Circle, Circle by 3 points, Ellipse, Ellipse by 3 points, Arc of ellipse, Arc of hyperbola, Arc of parabola, B-spline by control points, Periodic B-spline by control points, B-spline by knots, Periodic B-spline by knots, Polyline, Rectangle, Centered rectangle, Rounded rectangle, Triangle, Square, Pentagon, Hexagon, Heptagon, Octagon, Regular polygon, Slot, Fillet, Corner-preserving fillet, Trim, Extend, Split, External geometry, Carbon copy, Toggle construction geometry
- Sketcher constraints:
- Geometric constraints: Coincident, Point on object, Vertical, Horizontal, Parallel, Perpendicular, Tangent, Equal, Symmetric, Block
- Dimensional constraints: Lock, Horizontal distance, Vertical distance, Distance, Radius or weight, Diameter, Auto radius/diameter, Angle, Refraction (Snell's law)
- Constraint tools: Toggle driving/reference constraint, Activate/deactivate constraint
- Sketcher tools: Select unconstrained DoF, Select associated constraints, Select associated geometry, Select redundant constraints, Select conflicting constraints, Show/hide internal geometry, Select origin, Select horizontal axis, Select vertical axis, Symmetry, Clone, Copy, Move, Rectangular array, Remove axes alignment, Delete all geometry, Delete all constraints
- Sketcher B-spline tools: 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, Convert geometry to B-spline, Increase B-spline degree, Decrease B-spline degree, Increase knot multiplicity, Decrease knot multiplicity, Insert knot, Join curves
- Sketcher virtual space: Switch virtual space
- Additional: Sketcher Dialog, Preferences, Sketcher scripting
User documentation
- Getting started
- Installation: Download, Windows, Linux, Mac, Additional components, Docker, AppImage, Ubuntu Snap
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