Circle¶

⚙️ Spec sheet → — visual schematic and metrics measured from a real rendered STL.

Circles, ellipses, arcs, keyholes and rings.

pybosl2.shapes2d.circle.circle(radius=None, diameter=None, points=None, corner=None, anchor=Anchor.CENTER, spin=0, fn=None, fa=None, fs=None)[source]¶

Return a circle, built with the builtin circle(), by radius/diameter, or fit to points.

If corner is given three 2-D points, the circle is centered to be tangent to both segments of that path, on the inside corner. If points is given three 2-D points, the circle is centered and sized to pass through all three points. Anchor/spin are ignored for the corner/points forms, matching BOSL2.

Parameters:¶

radius : float | None¶: radius of the circle
diameter : float | None¶: diameter of the circle
points : Sequence[Sequence[float]] | None¶: three 2-D points the circle should pass through
corner : Sequence[Sequence[float]] | None¶: three 2-D points defining a path the circle should be tangent to
anchor : Anchor | Sequence[float]¶: anchor point (default CENTER)
spin : float¶: Z-axis rotation in degrees after anchor (default 0)
fn : int | None¶: arc smoothness overrides
fa : float | None¶: arc smoothness overrides
fs : float | None¶: arc smoothness overrides

Return type:¶

Bosl2Shape2D

Examples

from pybosl2 import shapes2d as s2

s2.circle(radius=15).linear_extrude(height=5).show()

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pybosl2.shapes2d.circle.arc(count=None, radius=None, angle=None, diameter=None, center=None, points=None, corner=None, width=None, thickness=None, start=None, wedge=False, long=False, clockwise=False, counterclockwise=False, endpoint=True, fn=None, fa=None, fs=None)[source]¶

Return a 2-D arc, returned as a Path2D of points (BOSL2’s arc()).

All of BOSL2’s 2-D arc specifications are supported (3-D arcs, which project onto a plane, are not):

arc(radius=, angle=, [start=], [center=]) – radius about center, sweeping angle degrees from start (or angle=[start, end] for an explicit range).
arc(width=, thickness=) – a circular segment starting and ending on the X axis.
arc(center=, points=[P0, P1]) – around center from P0 toward the direction of P1; the short way by default, or the long/clockwise/counterclockwise way.
arc(points=[P0, P1, P2]) – through three points, from P0 via P1 to P2.
arc(corner=[P0, P1, P2], radius=) – the fillet arc of radius tangent to both legs of the corner P0-P1-P2.

Set wedge=True to prepend the centre point, giving a closed pie/sector path. When count is omitted the point count follows OpenSCAD’s $fn/$fa/$fs rules, matching BOSL2.

Parameters:¶

count : int | None¶: number of points (default: from $fn/$fa/$fs)
radius : float | None¶: radius of the arc
diameter : float | None¶: diameter of the arc
angle : float | Sequence[float] | None¶: degrees to sweep from start, or [start, end]
center : Sequence[float] | None¶: centre point (default [0, 0])
points : Sequence[Sequence[float]] | None¶: two points (with center) or three points the arc passes through
corner : Sequence[Sequence[float]] | None¶: three points; the arc is the radius fillet tangent to both legs
width : float | None¶: chord width for the width/thickness form
thickness : float | None¶: height of the circular segment for the width/thickness form
start : float | None¶: starting angle in degrees (default 0)
wedge : bool¶: prepend the centre point, producing a closed sector (default False)
long : bool¶: for the two-point form, take the long way / a given handedness
clockwise : bool¶: for the two-point form, take the long way / a given handedness
counterclockwise : bool¶: for the two-point form, take the long way / a given handedness
endpoint : bool¶: include the final point (default True)
fn : int | None¶: number of fragments for circle resolution.
fa : float | None¶: minimum fragment angle for circle resolution.
fs : float | None¶: minimum fragment size for circle resolution.

Returns:¶

A Path2D (closed when wedge is set).

Return type:¶

Path2D

pybosl2.shapes2d.circle.ellipse(radius=None, diameter=None, realign=False, circumscribe=False, uniform=False, anchor=Anchor.CENTER, spin=0, fn=None, fa=None, fs=None)[source]¶

Return an ellipse (approximated as a polygon), built directly with polygon().

Note: uniform (equal-length approximating segments) is not implemented; segments are evenly spaced by angle instead.

Parameters:¶

radius : float | Sequence[float] | None¶: radius of the circle, or pair of semi-axes of the ellipse
diameter : float | Sequence[float] | None¶: diameter of the circle, or pair giving the full X/Y axis lengths
realign : bool¶: shift the first polygon point off the X+ axis (default False)
circumscribe : bool¶: circumscribe rather than inscribe the ideal ellipse (default False)
uniform : bool¶: use equal-length approximating segments (not implemented; evenly spaced by angle)
anchor : Anchor | Sequence[float]¶: anchor point (default CENTER)
spin : float¶: Z-axis rotation in degrees after anchor (default 0)
fn : int | None¶: arc smoothness overrides
fa : float | None¶: arc smoothness overrides
fs : float | None¶: arc smoothness overrides

Return type:¶

Bosl2Shape2D

Examples

from pybosl2 import shapes2d as s2

s2.ellipse(diameter=[30, 20]).linear_extrude(height=5).show()

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pybosl2.shapes2d.circle.keyhole(length=None, radius1=None, radius2=None, shoulder_radius=0, diameter1=None, diameter2=None, _length=None, anchor=Anchor.CENTER, spin=0, fn=None, fa=None, fs=None)[source]¶

Return a keyhole slot – a small circle joined to a larger one by tangent shoulders (BOSL2 keyhole()).

Parameters:¶

length : float | None¶: overall length between the two circle centers (default 15)
radius1 : float | None¶: radius/diameter of the small (bottom) circle (default 5)
diameter1 : float | None¶: radius/diameter of the small (bottom) circle (default 5)
radius2 : float | None¶: radius/diameter of the large (top) circle (default 10)
diameter2 : float | None¶: radius/diameter of the large (top) circle (default 10)
shoulder_radius : float¶: fillet radius where the shoulders meet the circles (default 0)
anchor : Anchor | Sequence[float]¶: standard BOSL2 2-D anchor / spin
spin : float¶: standard BOSL2 2-D anchor / spin
fn : int | None¶: number of fragments for circle resolution.
fa : float | None¶: minimum fragment angle for circle resolution.
fs : float | None¶: minimum fragment size for circle resolution.
_length : float | None¶

Return type:¶

Bosl2Shape2D

Examples

from pybosl2 import shapes2d as s2

s2.keyhole(length=25, radius1=4, radius2=9, shoulder_radius=2).linear_extrude(height=4).show()

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pybosl2.shapes2d.circle.ring(sides=None, ring_width=None, radius=None, radius1=None, radius2=None, diameter=None, diameter1=None, diameter2=None, angle=None, anchor=Anchor.CENTER, spin=0, fn=None, fa=None, fs=None)[source]¶

Return a 2-D ring (annulus) between two concentric radii (BOSL2 ring(), full-annulus form).

Give either both radii (radius1/radius2 or diameter1/diameter2) or one radius plus ring_width. The arc / 3-point / corner / width+thickness forms of BOSL2 ring() are not ported.

Parameters:¶

radius1 : float | None¶: the two radii/diameters
radius2 : float | None¶: the two radii/diameters
diameter1 : float | None¶: the two radii/diameters
diameter2 : float | None¶: the two radii/diameters
radius : float | None¶: one radius plus the wall width
diameter : float | None¶: one radius plus the wall width
ring_width : float | None¶: one radius plus the wall width
sides : int | None¶: number of sides (overrides the smoothness overrides)
angle : float | None¶: sweep angle in degrees (only the full-annulus form is ported; angle must be None)
anchor : Anchor | Sequence[float]¶: standard BOSL2 2-D anchor / spin
spin : float¶: standard BOSL2 2-D anchor / spin
fn : int | None¶: number of fragments for circle resolution.
fa : float | None¶: minimum fragment angle for circle resolution.
fs : float | None¶: minimum fragment size for circle resolution.

Return type:¶

Bosl2Shape2D

Examples

from pybosl2 import shapes2d as s2

s2.ring(radius=20, ring_width=4).linear_extrude(height=5).show()

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pybosl2.shapes2d.circle.glued_circles(radius=None, spread=10, tangent=30, diameter=None, anchor=Anchor.CENTER, spin=0, fn=None, fa=None, fs=None)[source]¶

Two circles joined by a curved waist, like a dumbbell, built directly with polygon().

Parameters:¶

radius : float | None¶: radius of the end circles
spread : float¶: distance between the centers of the end circles (default 10)
tangent : float¶: angle in degrees of the tangent point of the joining arcs, from the Y axis (default 30)
diameter : float | None¶: diameter of the end circles (alternative to radius)
anchor : Anchor | Sequence[float]¶: anchor point (default CENTER)
spin : float¶: Z-axis rotation in degrees after anchor (default 0)
fn : int | None¶: arc smoothness overrides
fa : float | None¶: arc smoothness overrides
fs : float | None¶: arc smoothness overrides

Return type:¶

Bosl2Shape2D

Examples

from pybosl2 import shapes2d as s2

s2.glued_circles(radius=10, spread=25, tangent=30).linear_extrude(height=5).show()

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pybosl2.shapes2d.circle.reuleaux_polygon(sides=3, radius=None, diameter=None, anchor=Anchor.CENTER, spin=0, fn=None, fa=None, fs=None)[source]¶

Return a Reuleaux polygon (constant-width curved-side shape), built directly with polygon().

Parameters:¶

sides : int¶: number of “sides”; must be an odd positive number (default 3)
radius : float | None¶: scale the shape to fit in a circle of this radius
diameter : float | None¶: scale the shape to fit in a circle of this diameter
anchor : Anchor | Sequence[float]¶: anchor point (default CENTER)
spin : float¶: Z-axis rotation in degrees after anchor (default 0)
fn : int | None¶: arc smoothness overrides
fa : float | None¶: arc smoothness overrides
fs : float | None¶: arc smoothness overrides

Return type:¶

Bosl2Shape2D

Examples

from pybosl2 import shapes2d as s2

s2.reuleaux_polygon(sides=3, radius=15).linear_extrude(height=5).show()

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