Sketcher: Elipsă definită prin 3 Puncte

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Sketcher CreateEllipse3Point

poziția meniului
Sketch → Sketcher geometries → Create ellipse by 3 points
Ateliere
Sketcher
scurtătură
nici unul
Prezentat în versiune
0.15
A se vedea, de asemenea,
Sketcher Ellipse by center, Sketcher Circle, Sketcher Arc of Ellipse

Descriere

When starting the tool, the mouse pointer changes to a white cross with a red ellipse icon.

Utiolizare

Versiune

  • 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.