Sketcher CreateEllipseByCenter/ru

Нарисовать коническое сечение

Эллипс по 3 точкам

Sketcher

Sketcher Эллипс по центральной точке
Системное название
Sketcher Create Ellipse by center
Расположение в меню
Эскиз → Геометрия эскиза → Эллипс по центральной точке
Верстаки
Sketcher
Быстрые клавиши
Нет
Представлено в версии
0.15
См. также
Sketcher Эллипс по 3 точкам, Sketcher Круг, Sketcher Дуга по эллипсу

Описание

Этот инструмент рисует эллипс, указывая три точки: центральную, конец большого радиуса, малый радиус. При запуске инструмента указатель мыши меняется на белый крест с красным значком эллипса. Кроме того, координаты отображаются в режиме реального времени.

The sequence of clicks is indicated by yellow arrows with numbers. C is the center, a - major diameter, b - minor diameter, F1, F2 are foci.

How to use

• Invoke the command by clicking a toolbar button, picking the menu item, or by using keyboard shortcut (needs to be assigned first in Interface Customization).
• First click in 3D view sets ellipse center. Second click sets the first radius and orientation of the ellipse. Third click sets the other radius (the distance from the line defined by first two clicks is the second radius).
• After the third click, the ellipse is created, together with a set of construction geometry aligned to it (major diameter, minor diameter, two foci). The construction geometry can be manually deleted if not needed, and recreated later. See Internal Alignment Constraint and Sketcher Show Hide Internal Geometry.
• Pressing ESC or clicking the right mouse button cancels the function.

Peculiarities

• 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.
• 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.

Create a conic

Ellipse by 3 points

Sketcher

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

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• 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

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• 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

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• 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

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• 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

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• Sketcher virtual space: Switch virtual space

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• Additional: Sketcher Dialog, Preferences, Sketcher scripting

User documentation

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• Installation: Download, Windows, Linux, Mac, Additional components, Docker, AppImage, Ubuntu Snap
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