3D graphics

3d graphical primitives which build on Matplotlib plot_wireframe and plot_surface.

plot_cone(radius, height, resolution=50, flip=False, centre=(0, 0, 0), ends=False, pose=None, ax=None, filled=False, **kwargs)[source]

Plot a cone using matplotlib

Parameters

radius (float) – radius of cone at open end
height (float) – height of cone in the z-direction
resolution (Optional[int]) – number of points on circumferece, defaults to 50
flip (Optional[bool]) – cone faces upward, defaults to False
ends (Optional[bool]) – add a surface for the base of the cone
pose (SE3, optional) – pose of cone, defaults to None
ax (Optional[Axes]) – axes to draw into, defaults to None
filled (bool, optional) – draw filled polygon, else wireframe, defaults to False
kwargs – arguments passed to plot_wireframe or plot_surface

Returns

matplotlib objects

Return type

list of matplotlib object types

The axis of the cone is parallel to the z-axis and it is drawn pointing down. The point is at z=0 and the open end at z= height. If flip is True then the cone faces upwards, the point is at z= height and the open end at z=0.

The cylinder can be positioned by setting centre, or positioned and orientated by setting pose.

Example:

>>> plot_cone(radius=1, height=2)

(Source code, png, hires.png, pdf)

Seealso: plot_surface(), plot_wireframe()

plot_cuboid(sides=(1, 1, 1), centre=(0, 0, 0), pose=None, ax=None, filled=False, **kwargs)[source]

Plot a cuboid (3D box) using matplotlib

Parameters

sides (array_like(3), optional) – side lengths, defaults to 1
centre (array_like(3), optional) – centre of box, defaults to (0, 0, 0)
pose (SE3, optional) – pose of sphere, defaults to None
ax (Axes3D, optional) – axes to draw into, defaults to None
filled (bool, optional) – draw filled polygon, else wireframe, defaults to False
kwargs – arguments passed to plot_wireframe or plot_surface

Returns

matplotlib collection

Return type

Line3DCollection or Poly3DCollection

Example:

>>> plot_cone(radius=1, height=2)

(Source code, png, hires.png, pdf)

Seealso: plot_surface(), plot_wireframe()

plot_cylinder(radius, height, resolution=50, centre=(0, 0, 0), ends=False, pose=None, ax=None, filled=False, **kwargs)[source]

Plot a cylinder using matplotlib

Parameters

radius (float) – radius of cylinder
height (float or array_like(2)) – height of cylinder in the z-direction
resolution (Optional[int]) – number of points on circumference, defaults to 50
centre (Union[List, Tuple[float, float, float], ndarray[Any, dtype[TypeVar(ScalarType, bound= generic, covariant=True)]], None]) – position of centre
pose (SE3, optional) – pose of cylinder, defaults to None
ax (Axes3D, optional) – axes to draw into, defaults to None
filled (bool, optional) – draw filled polygon, else wireframe, defaults to False
kwargs – arguments passed to plot_wireframe or plot_surface

Returns

matplotlib objects

Return type

list of matplotlib object types

The axis of the cylinder is parallel to the z-axis and extends from z=0 to z=height, or z=height[0] to z=height[1].

The cylinder can be positioned by setting centre, or positioned and orientated by setting pose.

Example:

>>> plot_cylinder(radius=1, height=(1,3))

(Source code, png, hires.png, pdf)

Seealso: plot_surface(), plot_wireframe()

plot_ellipsoid(E, centre=(0, 0, 0), scale=1, confidence=None, resolution=40, inverted=False, ax=None, **kwargs)[source]

Draw an ellipsoid using matplotlib

Parameters

E (ndarray(3,3)) – ellipsoid
centre (tuple, optional) – [description], defaults to (0,0,0)
scale (Optional[float]) –
confidence (float) – confidence interval, range 0 to 1
resolution (int, optional) – number of points on circumferece, defaults to 40
inverted (bool, optional) – \(E^{-1}\) rather than \(E\) provided, defaults to False
ax ([type], optional) – [description], defaults to None
wireframe (bool, optional) – [description], defaults to False
stride (int, optional) – [description], defaults to 1

plot_ellipsoid(E) draws the ellipsoid defined by \(x^T \mat{E} x = 0\) on the current plot.

Example:

>>> plot_ellipsoid(np.diag([1, 2, 3]), [1, 1, 0], color="r", resolution=10); # draw red ellipsoid

(Source code, png, hires.png, pdf)

Note

If a confidence interval is given then E is interpretted as a covariance

matrix and the ellipse size is computed using an inverse chi-squared function.

Seealso: plot_surface(), plot_wireframe()
Return type: List[Artist]

plot_sphere(radius, centre=(0, 0, 0), pose=None, resolution=50, ax=None, **kwargs)[source]

Plot a sphere using matplotlib

Parameters

centre (array_like(3), ndarray(3,N), optional) – centre of sphere, defaults to (0, 0, 0)
radius (float, optional) – radius of sphere, defaults to 1
resolution (int, optional) – number of points on circumferece, defaults to 50
pose (SE3, optional) – pose of sphere, defaults to None
ax (Axes3D, optional) – axes to draw into, defaults to None
filled (bool, optional) – draw filled polygon, else wireframe, defaults to False
kwargs – arguments passed to plot_wireframe or plot_surface

Returns

matplotlib collection

Return type

list of Line3DCollection or Poly3DCollection

Plot one or more spheres. If centre is a 3xN array, then each column is taken as the centre of a sphere. All spheres have the same radius, color etc.

Example:

>>> from spatialmath.base import plot_sphere
>>> plot_sphere(radius=1, color="r", resolution=10)   # red sphere wireframe
>>> plot_sphere(radius=1, centre=(1,1,1), filled=True, facecolor='b')

(Source code, png, hires.png, pdf)

(Source code, png, hires.png, pdf)

Seealso: plot_surface(), plot_wireframe()

plotvol3(dim=None, ax=None, equal=True, grid=False, labels=True, projection='ortho', new=False)[source]

Create 3D plot volume

Parameters

ax (Axes3DSubplot, optional) – axes of initializer, defaults to new subplot
equal (bool) – set aspect ratio to 1:1:1, default False

Returns

initialized axes

Return type

Axes3DSubplot

Initialize axes with dimensions given by dim which can be:

input	xrange	yrange	zrange
A (scalar)	-A:A	-A:A	-A:A
[A, B]	A:B	A:B	A:B
[A, B, C, D, E, F]	A:B	C:D	E:F

Seealso: plotvol2(), expand_dims()